Page 3 of 5
Leaf with spots Black & White Stock Photos
RMPG43J4–. Cabbage, cauliflower and allied vegetables : from seed to harvest . Vegetable gardening; Cabbage; Cauliflower. 122 FUNGOUS DISEASES. are a sure sign of the black rot, showing that the germs have already passed from the leaves into the stems. If the stem of a healthy cabbage leaf be cut across, these vessels are seen forming faint yellowish spots in the interior, in marked contrast to the black spots seen in the badly diseased leaf. In case of .V. Fig. j6—Healthy Cabbage Leaf, Showing Water Beads Along the Margin. leaves which are but partly diseased, only those ves- sels leading into the dis
![. Diseases of economic plants . Plant diseases. TREES AND TIMBER 433 gray border. The spots, from 3-6 mm. in diameter, often coalesce to form large blotches which are fragile, sometimes dropping from the leaf. Young leaves develop poorly and are deformed, while severe infection may cause complete defoliation of the tree.. Fig. 188.- ' Cedar apple." gall of the rust fungus. Original. Macrosporiose (Macrosporium Catalpw Ell. & Mart.).— This spot is scarcely distinguishable from phyllostictose except through the absence of pycnidia and the presence of a scant quantity of Ijlack mold. Pow Stock Photo](https://c8.alamy.com/comp/RDE2HJ/diseases-of-economic-plants-plant-diseases-trees-and-timber-433-gray-border-the-spots-from-3-6-mm-in-diameter-often-coalesce-to-form-large-blotches-which-are-fragile-sometimes-dropping-from-the-leaf-young-leaves-develop-poorly-and-are-deformed-while-severe-infection-may-cause-complete-defoliation-of-the-tree-fig-188-cedar-applequot-gall-of-the-rust-fungus-original-macrosporiose-macrosporium-catalpw-ell-amp-mart-this-spot-is-scarcely-distinguishable-from-phyllostictose-except-through-the-absence-of-pycnidia-and-the-presence-of-a-scant-quantity-of-ijlack-mold-pow-RDE2HJ.jpg ". Diseases of economic plants . Plant diseases. TREES AND TIMBER 433 gray border. The spots, from 3-6 mm. in diameter, often coalesce to form large blotches which are fragile, sometimes dropping from the leaf. Young leaves develop poorly and are deformed, while severe infection may cause complete defoliation of the tree.. Fig. 188.- ' Cedar apple." gall of the rust fungus. Original. Macrosporiose (Macrosporium Catalpw Ell. & Mart.).— This spot is scarcely distinguishable from phyllostictose except through the absence of pycnidia and the presence of a scant quantity of Ijlack mold. Pow Stock Photo")
RMRDE2HJ–. Diseases of economic plants . Plant diseases. TREES AND TIMBER 433 gray border. The spots, from 3-6 mm. in diameter, often coalesce to form large blotches which are fragile, sometimes dropping from the leaf. Young leaves develop poorly and are deformed, while severe infection may cause complete defoliation of the tree.. Fig. 188.- ' Cedar apple." gall of the rust fungus. Original. Macrosporiose (Macrosporium Catalpw Ell. & Mart.).— This spot is scarcely distinguishable from phyllostictose except through the absence of pycnidia and the presence of a scant quantity of Ijlack mold. Pow
RMPG3T5M–. Manual of fruit diseases . Fruit. 50 MANUAL OF FRUIT DISEASES the diseased portion is sunken. Older spots become lobed, due to the secondary extension of the pathogene from one or more points in the leaf. This activity results in a series of more or less concentric areas mak- ing up an irregular spot, but in which the outline of the original diseased portion can still be recognized (Fig. 12). The center of the lesion be- comes grayish brown and the entire affected area presents an appear- ance which has given rise to the name frog-eye (Fig. 12). Frequently the small black fruiting bodies of
RMRDXNTG–. Botany of the living plant. Botany. PHYCOMYCETES.—(a) OOMYCETES 417 in America assumed epidemic virulence in Ireland, causing the great famine. Since that time the Potato crop has never been entirely free from it. The disease makes its appearance upon the leaves and stems as spots at first small and pale-coloured, but as they enlarge the centre of each becomes brown, and extends, though still with a pale margin, till the spots run together, and the whole leaf or even the whole shoot may be affected (Fig. 352). If leaves with young infected patches be examined on a damp still day, or better,
RMPG14TB–. Manual of tree diseases . Trees. BUCKEYE DISEASES 119 defoliation results in retanHnc; tlic growth of the trees and making tliem more susceptible to winter-injury. Si/mptoms. The lesions develop on the leaflets and petiole. AMien first evident, the spots are irregular in outline, slightly dis- colored and water-soaked in appearance. Later the center of the spot becomes red- dish brown and is sur- rounded by a yellowish zone which blends into the green of the healthy part of the leaf. Finally, the entire affected area turns brown and becomes dried and brittle (Fig. 14). The spots may be small
RMRDE3FE–. Minnesota plant diseases. Plant diseases. 284 Minnesota Plant Diseases. The leaf underneath the spots is abnormally increased in size and distorted in shape. The pycnidia usually accompany the cluster cups and come from the same mycelium', but are gen- erally to be found on the upper surface of the leaf. They are probably male-cell receptacles which have lost their fertilizing- power and are now functionless. They illustrate a persistence of a habit after its usefulness has passed, a by no means uncommon phenomenon in nature.. f ^ ^ 1 Fig. 140.—Stem rust of wheat (Puccinia graminis). A secti
RMPG3TPN–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 488 FUNGI IMPERFECTI. Faded spots appear on the leaves, becoming later greyish brown dotted over with minute black points, the couidial patches.' C. ampelinum Cav. causes little dry spots on the leaves of vine, fre- quently in such numbers that the whole leaf dries up. C. kentjae Hals, attacks palm-seedlings so that their leaves do not unfold. C. cyclameneae Hals, occurs on Cydamen. Scoleco-Allantosporae. Cylindrosp
![. Injurious insects : how to recognize and control them . Insect pests; Insect pests. 204 P£STS OF GARDEN AND FIELD CROPS The Onion Thrips {Thrips tahaci T.ind.) A great variety of truck crops and some flowering plants under glass are subject to injury" by this minute form of insect Ufe. The juices are sucked from the leaves, causing numerous tiny white spots. The iosect itself is so small as almost to escape notice. It is yellowish, slender, and one twenty-fifth of an inch long. Eggs are laid withia the leaf tissue. Several generations may be developed in a season. Crop remnants and neig Stock Photo](https://c8.alamy.com/comp/RDAMN5/injurious-insects-how-to-recognize-and-control-them-insect-pests-insect-pests-204-psts-of-garden-and-field-crops-the-onion-thrips-thrips-tahaci-tind-a-great-variety-of-truck-crops-and-some-flowering-plants-under-glass-are-subject-to-injuryquot-by-this-minute-form-of-insect-ufe-the-juices-are-sucked-from-the-leaves-causing-numerous-tiny-white-spots-the-iosect-itself-is-so-small-as-almost-to-escape-notice-it-is-yellowish-slender-and-one-twenty-fifth-of-an-inch-long-eggs-are-laid-withia-the-leaf-tissue-several-generations-may-be-developed-in-a-season-crop-remnants-and-neig-RDAMN5.jpg ". Injurious insects : how to recognize and control them . Insect pests; Insect pests. 204 P£STS OF GARDEN AND FIELD CROPS The Onion Thrips {Thrips tahaci T.ind.) A great variety of truck crops and some flowering plants under glass are subject to injury" by this minute form of insect Ufe. The juices are sucked from the leaves, causing numerous tiny white spots. The iosect itself is so small as almost to escape notice. It is yellowish, slender, and one twenty-fifth of an inch long. Eggs are laid withia the leaf tissue. Several generations may be developed in a season. Crop remnants and neig Stock Photo")
RMRDAMN5–. Injurious insects : how to recognize and control them . Insect pests; Insect pests. 204 P£STS OF GARDEN AND FIELD CROPS The Onion Thrips {Thrips tahaci T.ind.) A great variety of truck crops and some flowering plants under glass are subject to injury" by this minute form of insect Ufe. The juices are sucked from the leaves, causing numerous tiny white spots. The iosect itself is so small as almost to escape notice. It is yellowish, slender, and one twenty-fifth of an inch long. Eggs are laid withia the leaf tissue. Several generations may be developed in a season. Crop remnants and neig
RMPG0R6E–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. PHYTOPHTHORA. 121. Fig. 32.—Pkytopkthora infestans. The Potato disease. A, Potato leaf with brown spots and white patches of fuDgi on the lower side. £, Groups of conidio- phores emerging from a stoma close beside a hair of the potato leaf. C, Conidio- phores and conidia, much enlarged. B, Leaf of potato much shrivelled up and brown, as in the later stages of the disea-se. (y. Tubeuf del.). Please note that these im
RMRDDA8Y–. Lessons in botany. Botany. '3° BOTANY. pare in the same way from the yellow spots. To demonstrate the cluster cups, good cross-sections of the leaf through a spot should be made, or prepared slides should be obtained. Let the pupils sketch the form of the different spores, and other characters, and make notes of the observations. To demonstrate mycelium in the tissues, use the carnation rust which can be obtained in winter in greenhouses where the carnations are grown (see Chapter XV, paragraph 159), or fresh wheat leaves may be preserved in alcohol for making sections. 220. Wheat rust (Pucc
RMPG4DTM–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. DETAILED ACCOUNT OF SPECIFIC PLANT DISEASES 559 black or very dark brown at first, but changing to a lighter shade, as the spots grow older. The first diseased part of the leaf looks as if water- logged, and in a few days, the diseased part of the leaf peripheral to the central spot fades, or bleaches, to a yellow, or grayish-white. Here the disease may stop and the plants recover, the diseased areas separate from the healthy tissue and fall out leaving holes in the leaves. The disease
![. Florists' review [microform]. Floriculture. Februabx 25. 1915. The Florists' Revkw li^. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found n Stock Photo](https://c8.alamy.com/comp/RRRFDM/florists-review-microform-floriculture-februabx-25-1915-the-florists-revkw-li-stiomonose-hebaiids-spring-i-send-you-under-separate-cover-a-few-tops-of-carnations-that-seem-to-be-acting-strangely-only-a-few-of-the-plants-are-affected-can-you-inform-me-as-to-the-trouble-and-the-remedy-b-w-your-plants-are-affected-with-the-com-mon-disease-called-stigmonose-or-bac-teria-when-these-light-spots-spread-across-the-width-of-the-leaf-everything-above-that-point-dies-off-hence-the-dry-tips-i-have-discussed-this-trouble-with-many-prominent-carnation-growers-but-as-yet-have-found-n-RRRFDM.jpg ". Florists' review [microform]. Floriculture. Februabx 25. 1915. The Florists' Revkw li^. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found n Stock Photo")
RMRRRFDM–. Florists' review [microform]. Floriculture. Februabx 25. 1915. The Florists' Revkw li^. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found n
RMPG408J–. Manual of fruit diseases . Fruit. 238 MANUAL OF FRUIT DISEASES Symptoms. On the upper surface of the leaf the first signs of downy-mildew are in the form of small greenish yellow indefinite spots, the margins of which gradually merge into the darker green of. Fig. 61. — Downy-mildew on lower surface of grape-leaf. the leaf. In a short time there appears within the spot a net- work of small, reddish brown lines, the discolored smaller veins. These lines become more pronounced until the whole diseased portion is brown, dry and brittle, and eventually cracked. These symptoms apply particularly
RMRDGEY9–. An introduction to zoology, with directions for practical work (invertebrates). XXUI INSECTA : DIPTERA 355 The Pupa. suri'ounds them. When the larva is full grown it is about half an inch long, and two dark spots become visible on the thorax (Fig. 280, B)—a sign that pupation is about to occur. At this time the larva spins a little oval-shaped nest or cocoon, attaching the silk threads on each side to a leaf, and inside this the larval skin is thrown off. The pupa retains a good deal of power of movement, and it breaks away one end of the cocoon, so that it finally lies supported in a silken
RMPG4EM7–. Diseases of economic plants . Plant diseases. 230 DISEASES OF ECONOMIC PLANTS Black mold (Alternaria Brassicoe (Berk.) Sacc). — The affected spots are nearly black, marked concentrically, are circular, and are not definitely bordered, i.e., they shade off gradually into the surrounding healthy tissue.. Fig. 108. — Collard black mold as seen from upper side of the leaf. Original. They enlarge sometimes to 2-3 cm. in diameter. The tissue dries, becomes brittle, and often falls away, leaving ragged holes. The general appearance of the spot as seen from above is pale green; as seen from the lowe
RMRDE67T–. Farm friends and farm foes : a text-book of agricultural science . Agricultural pests; Beneficial insects; Insect pests. Spore GERMiNATrNG with Tube Germinating Tube among ENTERING SfOMATA; SEEN CELLS OF LEAF; SEEN FROM FROM ABOVE SIDE which becomes swollen with light green spots. Soon the skin breaks apart and the fungus threads produce great numbers of small round spores. The small swollen places where these spores are produced are called cecidia (singular, cecidiuni), and the spores produced in them are called CBcid- «fl/-spores or spring spores, because they develop in spring. These spri
RMPG1AFG–. North American trees : being descriptions and illustrations of the trees growing independently of cultivation in North America, north of Mexico and the West Indies . Trees. 834 The Catalpas prominently veined and glandular beneath; the leaf-stalks are stout, round, about i dm. long. The flowers, appearing from May to July, are in many-flowered panicles 2 to 2.5 dm. long, the calyx 8 to 12 mm. long, green or purplish; the white corolla bears 2 rows of yel- low spots, the tube bell-shaped, the limb 4 to 5 by 6 to 7 cm. across, the lower lobe nearly entire, with numerous purple spots. The fruit
![. Florists' review [microform]. Floriculture. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found no one who could offer a remedy for it. " Stock Photo](https://c8.alamy.com/comp/RRRFD9/florists-review-microform-floriculture-stiomonose-hebaiids-spring-i-send-you-under-separate-cover-a-few-tops-of-carnations-that-seem-to-be-acting-strangely-only-a-few-of-the-plants-are-affected-can-you-inform-me-as-to-the-trouble-and-the-remedy-b-w-your-plants-are-affected-with-the-com-mon-disease-called-stigmonose-or-bac-teria-when-these-light-spots-spread-across-the-width-of-the-leaf-everything-above-that-point-dies-off-hence-the-dry-tips-i-have-discussed-this-trouble-with-many-prominent-carnation-growers-but-as-yet-have-found-no-one-who-could-offer-a-remedy-for-it-quot-RRRFD9.jpg ". Florists' review [microform]. Floriculture. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found no one who could offer a remedy for it. " Stock Photo")
RMRRRFD9–. Florists' review [microform]. Floriculture. STIOMONOSE HEBAIiDS SPRING. I send you under separate cover a few tops of carnations that seem to be acting strangely. Only a few of the plants are affected. Can you inform me as to the trouble and the remedy? B. W. Your plants are affected with the com- mon disease called stigmonose or bac- teria. When these light spots spread across the width of the leaf, everything above that point dies off; hence the dry tips. I have discussed this trouble with many prominent carnation growers, but as yet have found no one who could offer a remedy for it. "
![. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 623 tapering, obtuse, basally dark-brown, slightly constricted at the septa, 5 to 9 times cross-septate and 0-5 times longitudinally septate. It causes injury on carnation leaves and stems. A. solani (E. & M.) Jones & Grout. '"• ^''''"'-'" Spots brown, circular to elliptic, concentrically zonate, amphige- nous, irregularly scattered over the leaf surface; mycelium. Fio. 422.—A. solani, 2, spores germinating and penetrating the living potato leaf; 5, showing cateuulatiou of Stock Photo](https://c8.alamy.com/comp/PG45GC/the-fungi-which-cause-plant-disease-plant-diseases-fungi-the-fungi-which-cause-plant-disease-623-tapering-obtuse-basally-dark-brown-slightly-constricted-at-the-septa-5-to-9-times-cross-septate-and-0-5-times-longitudinally-septate-it-causes-injury-on-carnation-leaves-and-stems-a-solani-e-amp-m-jones-amp-grout-quot-quot-quot-spots-brown-circular-to-elliptic-concentrically-zonate-amphige-nous-irregularly-scattered-over-the-leaf-surface-mycelium-fio-422a-solani-2-spores-germinating-and-penetrating-the-living-potato-leaf-5-showing-cateuulatiou-of-PG45GC.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 623 tapering, obtuse, basally dark-brown, slightly constricted at the septa, 5 to 9 times cross-septate and 0-5 times longitudinally septate. It causes injury on carnation leaves and stems. A. solani (E. & M.) Jones & Grout. '"• ^''''"'-'" Spots brown, circular to elliptic, concentrically zonate, amphige- nous, irregularly scattered over the leaf surface; mycelium. Fio. 422.—A. solani, 2, spores germinating and penetrating the living potato leaf; 5, showing cateuulatiou of Stock Photo")
RMPG45GC–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 623 tapering, obtuse, basally dark-brown, slightly constricted at the septa, 5 to 9 times cross-septate and 0-5 times longitudinally septate. It causes injury on carnation leaves and stems. A. solani (E. & M.) Jones & Grout. '"• ^''''"'-'" Spots brown, circular to elliptic, concentrically zonate, amphige- nous, irregularly scattered over the leaf surface; mycelium. Fio. 422.—A. solani, 2, spores germinating and penetrating the living potato leaf; 5, showing cateuulatiou of
![. Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These tufts of threads, which, like the spore Stock Photo](https://c8.alamy.com/comp/RJ6M38/grasses-of-north-america-microform-chapters-on-the-physiology-composition-selection-improving-and-cultivation-of-grasses-management-of-grass-lands-also-chapters-on-clovers-injurious-insects-and-fungi-grasses-forage-plants-gramines-plantes-fourragres-in-the-earlier-part-of-the-season-small-avhitisli-or-iale-lrown-spots-appear-in-the-leaf-which-contains-the-mycelium-of-a-fungus-this-fruits-on-the-lower-surface-producing-num-erous-tufts-of-necklace-shaped-threads-each-of-which-ends-in-a-celled-egg-shaped-conidia-s-ore-these-tufts-of-threads-which-like-the-spore-RJ6M38.jpg ". Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These tufts of threads, which, like the spore Stock Photo")
RMRJ6M38–. Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These tufts of threads, which, like the spore
RMPG3RWT–. Manual of fruit diseases . Fruit. APPLE DISEASES 65 Symptoms. The presence of apple-rust in any localit}- may be detected by examining the apple or the cedar. On the apple leaves young spots may be fovuKl from April to June. At first these are seen on the upper surface as minute pale-yellow areas. Fig. 17. â Apple-rust; on lower surface (on leaf at extreme left), and on upper surface (three leaves on right). (Fig. 17, right). These enlarge, become darker, and finally are orange-colored. On the upper surface of the spots the fruiting bodies of the pathogene develop, first as minute, yellow, f
![. Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. THE BLACK-SPOT DISEASE OF CLOVER. 486. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These Stock Photo](https://c8.alamy.com/comp/RJ6M3T/grasses-of-north-america-microform-chapters-on-the-physiology-composition-selection-improving-and-cultivation-of-grasses-management-of-grass-lands-also-chapters-on-clovers-injurious-insects-and-fungi-grasses-forage-plants-gramines-plantes-fourragres-the-black-spot-disease-of-clover-486-in-the-earlier-part-of-the-season-small-avhitisli-or-iale-lrown-spots-appear-in-the-leaf-which-contains-the-mycelium-of-a-fungus-this-fruits-on-the-lower-surface-producing-num-erous-tufts-of-necklace-shaped-threads-each-of-which-ends-in-a-celled-egg-shaped-conidia-s-ore-these-RJ6M3T.jpg ". Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. THE BLACK-SPOT DISEASE OF CLOVER. 486. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These Stock Photo")
RMRJ6M3T–. Grasses of North America [microform] : chapters on the physiology, composition, selection, improving and cultivation of grasses, management of grass lands, also chapters on clovers, injurious insects and fungi. Grasses; Forage plants; Graminées; Plantes fourragères. THE BLACK-SPOT DISEASE OF CLOVER. 486. In the earlier part of the season small Avhitisli or i)ale-l)rown spots appear in the leaf, which contains the mycelium of a fungus. This fruits on the lower surface, producing num- erous tufts of necklace-shaped threads, each of which ends in a ^.'-celled, egg- shaped conidia-s])ore. These
RMPG45MH–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 561 spots but since diseased tissue soon drops out they are often diffi- cult to find. Bark spots are often sterile. Late in the season spores abound scattered on the surfaces of twigs, especially at rough places, as near leaf scars. Spores near bud scales penetrate them with a mycelium and kill the buds or if on bark they enter the twig and produce dead spots. C. foliicolum Fuckel.^o^ Spots epiphyllous, ochraceous, indefinite; acervuli punctiform, erumpent; conidia ellipsoid-oblong, 17 x 6-7 /i,
![. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 514 SPECIAL PLANT PATHOLOGY to the grape" leaves (Fig. 186), where it produces under ordinary conditions spots of mildew, especiaUy on the lower leaf surface. In bad cases, the whole lower leaf surface may be covered with the downy, or cottony mass of hyphae which gives the fungus its common name. The parasitic hyphae live in the intercellular spaces of the host and send into the host cells smaU knob-like haustoria. The presence of the mycelium seriously interferes with the normal Stock Photo](https://c8.alamy.com/comp/RDE1F2/a-text-book-of-mycology-and-plant-pathology-plant-diseases-fungi-in-agriculture-plant-diseases-fungi-514-special-plant-pathology-to-the-grapequot-leaves-fig-186-where-it-produces-under-ordinary-conditions-spots-of-mildew-especiauy-on-the-lower-leaf-surface-in-bad-cases-the-whole-lower-leaf-surface-may-be-covered-with-the-downy-or-cottony-mass-of-hyphae-which-gives-the-fungus-its-common-name-the-parasitic-hyphae-live-in-the-intercellular-spaces-of-the-host-and-send-into-the-host-cells-smau-knob-like-haustoria-the-presence-of-the-mycelium-seriously-interferes-with-the-normal-RDE1F2.jpg ". A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 514 SPECIAL PLANT PATHOLOGY to the grape" leaves (Fig. 186), where it produces under ordinary conditions spots of mildew, especiaUy on the lower leaf surface. In bad cases, the whole lower leaf surface may be covered with the downy, or cottony mass of hyphae which gives the fungus its common name. The parasitic hyphae live in the intercellular spaces of the host and send into the host cells smaU knob-like haustoria. The presence of the mycelium seriously interferes with the normal Stock Photo")
RMRDE1F2–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 514 SPECIAL PLANT PATHOLOGY to the grape" leaves (Fig. 186), where it produces under ordinary conditions spots of mildew, especiaUy on the lower leaf surface. In bad cases, the whole lower leaf surface may be covered with the downy, or cottony mass of hyphae which gives the fungus its common name. The parasitic hyphae live in the intercellular spaces of the host and send into the host cells smaU knob-like haustoria. The presence of the mycelium seriously interferes with the normal
RMPG45GR–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 617. Fia. 416.—Sporodesmium antiquum. After Sac- caxdo. S. exitiosum var. solani Schenck is reported as the cause of a potato disease. S. solani-varians Yanha is the cause of potato disease in Europe, the foliage bearing brown spots and finally dying in a manner resembling death caused by Phytophthora. Cladosporium and pycnidial forms are said to exist. S. mucosum Sacc. was reported by Ader- holt on cucumber fruit and leaves causing disease. S. scorzonerae Aderh. causes a salsify stem and leaf di
RMRD8YJ3–. Insects injurious to fruits. Illustrated with four hundred and forty wood-cuts. Insect pests. Fig. 396. extremity of the abdomen—that they are quite useless for the purpose of flight. Their eggs are deposited in the ground. Since they cannot fly, they may easily be destroyed by hand. No. 246.—The Leaf-footed Plant-bug. Leptoglossusphyllopus (Linn.). The leaf-footed plant-bug is of a reddish- brown color, with a long, sharp beak, and a transverse yellowish-white band across its wing-covers. The wings, when raised, show the body, which is of a bright-red color, with black spots. The shanks of
RMPG4EXX–. Culture of the citrus in California . Citrus fruits; Fruit-culture. INSECT PESTS AFFECTING THE CITRUS. 249 This species diflers but slightly from A. aurantii, excepting in habits and color. Scale of female circular, body pale yellow. Male smaller than female, nearly circular, white, marked with irregular yellow spots. Viviparous. This species only attacks the leaves and fruit, seldom the wood. Supposed to have been introduced from Japan in 1872. Treatment.—Rosin solution (formula No. 1), and gas treat- ment (formula No. 4).. Yellow Scale on leaf. Ventral view of insect. (3) Oleander Scale. A
RMRE0BMH–. The wonder of life. Biology; Natural history; Zoology. 540 THE WONDER OF LIFE. Kallima, which is conspicuously coloured on the upper surface, but becomes like a withered leaf when it folds its wings together and exposes the brown under surface (Fig. 11). As we have noted, the nervures on the wings look Hke the veins on a leaf, and the sug- gestion of a mid- rib increases the resemblance. Spots on the wings look like holes on the leaf, and so on. In fact, perfection is attained by the combination of a number of items. Even the fact that the colora- tion of the under surface and the position o
RMPG14P8–. Manual of tree diseases . Trees. ELM DISEASES 153 every season on the leaves in late autumn just before the leaves fall. The first indications of the spots are seen on the upper surface of the leaf. The dead leaf-tissue is grayish, and either scat- tered over the spot or grouped in the center are one or more black pustules (Fig. 21). The under sur- face of the leaf shows no evidence of the spot until later in the season, when brown dead areas appear with a few raised pustules. After the leaves fall to the ground, fruiting-bodies containing ascospores de- velop which are the source of primary
RMRDTEAK–. The bulb book; or, Bulbous and tuberous plants for the open air, stove, and greenhouse, containing particulars as to descriptions, culture, propagation, etc., of plants from all parts of the world having bulbs, corms, tubers, or rhizomes (orchids excluded). Bulbs (Plants). CALOCHOETUS THE BULB BOOK CALOCHOETUS species 9 to 18 ins. high, with a long glossy leaf, and large creamy-white flowers. C. Kennedy!.—This is a striking and beautiful species about 18 ins. high, freely producing in early summer its large bright orange-red or scarlet flowers, the black spots near the base being surrounded
![. The fungi which cause plant disease . Plant diseases; Fungi. Fig. 351.—Actinonema rosae. 3, branching strand of superficial mycelium; 4, spores. After Southworth. A. manihotes Hen. on cassava in Africa. A. tremulae Sacc. occurs on aspen; A. melutispora B. & Br. on ash. Actinonema Fries (p. 505) Pyenidia very small, not ostiolate, with a radiating mycelial growth on the surface of the host; conidia elongate, on short conidiophores. A genus of about fifteen species, chiefly leaf parasites. A. rosse (Lib.) Fr.^'*- "« Spots rounded or irregular, black or purple, epiphyllous, often. Plea Stock Photo](https://c8.alamy.com/comp/PG45RA/the-fungi-which-cause-plant-disease-plant-diseases-fungi-fig-351actinonema-rosae-3-branching-strand-of-superficial-mycelium-4-spores-after-southworth-a-manihotes-hen-on-cassava-in-africa-a-tremulae-sacc-occurs-on-aspen-a-melutispora-b-amp-br-on-ash-actinonema-fries-p-505-pyenidia-very-small-not-ostiolate-with-a-radiating-mycelial-growth-on-the-surface-of-the-host-conidia-elongate-on-short-conidiophores-a-genus-of-about-fifteen-species-chiefly-leaf-parasites-a-rosse-lib-fr-quot-spots-rounded-or-irregular-black-or-purple-epiphyllous-often-plea-PG45RA.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. Fig. 351.—Actinonema rosae. 3, branching strand of superficial mycelium; 4, spores. After Southworth. A. manihotes Hen. on cassava in Africa. A. tremulae Sacc. occurs on aspen; A. melutispora B. & Br. on ash. Actinonema Fries (p. 505) Pyenidia very small, not ostiolate, with a radiating mycelial growth on the surface of the host; conidia elongate, on short conidiophores. A genus of about fifteen species, chiefly leaf parasites. A. rosse (Lib.) Fr.^'*- "« Spots rounded or irregular, black or purple, epiphyllous, often. Plea Stock Photo")
RMPG45RA–. The fungi which cause plant disease . Plant diseases; Fungi. Fig. 351.—Actinonema rosae. 3, branching strand of superficial mycelium; 4, spores. After Southworth. A. manihotes Hen. on cassava in Africa. A. tremulae Sacc. occurs on aspen; A. melutispora B. & Br. on ash. Actinonema Fries (p. 505) Pyenidia very small, not ostiolate, with a radiating mycelial growth on the surface of the host; conidia elongate, on short conidiophores. A genus of about fifteen species, chiefly leaf parasites. A. rosse (Lib.) Fr.^'*- "« Spots rounded or irregular, black or purple, epiphyllous, often. Plea
![. In nature's workshop [microform]. Sciences de la vie; Natural history; Life sciences; Sciences naturelles. Animal and Vegetable Hedgehogs 167 or two species which, though they look much hke other thistles both in foliage and flower, have really no actual prickles at all ; the ends and angles of the leaves, while shaped as in the armed sorts, are quite soft and yielding. Then there are more advanced types which have hard prickly points to every lobe of the leaf, but still can be grasped by the smooth and un- armed stem; ^Kse kinds live mostly in rather exposed spots, but not in those where co Stock Photo](https://c8.alamy.com/comp/RENT4H/in-natures-workshop-microform-sciences-de-la-vie-natural-history-life-sciences-sciences-naturelles-animal-and-vegetable-hedgehogs-167-or-two-species-which-though-they-look-much-hke-other-thistles-both-in-foliage-and-flower-have-really-no-actual-prickles-at-all-the-ends-and-angles-of-the-leaves-while-shaped-as-in-the-armed-sorts-are-quite-soft-and-yielding-then-there-are-more-advanced-types-which-have-hard-prickly-points-to-every-lobe-of-the-leaf-but-still-can-be-grasped-by-the-smooth-and-un-armed-stem-kse-kinds-live-mostly-in-rather-exposed-spots-but-not-in-those-where-co-RENT4H.jpg ". In nature's workshop [microform]. Sciences de la vie; Natural history; Life sciences; Sciences naturelles. Animal and Vegetable Hedgehogs 167 or two species which, though they look much hke other thistles both in foliage and flower, have really no actual prickles at all ; the ends and angles of the leaves, while shaped as in the armed sorts, are quite soft and yielding. Then there are more advanced types which have hard prickly points to every lobe of the leaf, but still can be grasped by the smooth and un- armed stem; ^Kse kinds live mostly in rather exposed spots, but not in those where co Stock Photo")
RMRENT4H–. In nature's workshop [microform]. Sciences de la vie; Natural history; Life sciences; Sciences naturelles. Animal and Vegetable Hedgehogs 167 or two species which, though they look much hke other thistles both in foliage and flower, have really no actual prickles at all ; the ends and angles of the leaves, while shaped as in the armed sorts, are quite soft and yielding. Then there are more advanced types which have hard prickly points to every lobe of the leaf, but still can be grasped by the smooth and un- armed stem; ^Kse kinds live mostly in rather exposed spots, but not in those where co
![. The fungi which cause plant disease . Plant diseases; Fungi. 556 THE FUNGI WHICH CAUSE PLANT DISEASE CI^N ' 100-120 /I, or by confluence larger; I /vO conidia abundant, clavate or wedge- ^ shaped, 11-15 x 2.5-3 n. The cause of leaf perforations of lettuce. M. violae (Pass.) Sacc."' Discoloration of the host slight; ^ ^^-^ 2^:^^yy acervuli nvunerous, scattered, small; ,,^ (f""" â conidia curved, or straight, 15-18 x yK^;;;-y^ J 5-6 ii, septum usually excentric. T, â,, ., , Small spots are produced on violet Fig. 374.âMarssonia violse. Spores and conidiophores. leaveS. Stock Photo](https://c8.alamy.com/comp/PG45MK/the-fungi-which-cause-plant-disease-plant-diseases-fungi-556-the-fungi-which-cause-plant-disease-cin-100-120-i-or-by-confluence-larger-i-vo-conidia-abundant-clavate-or-wedge-shaped-11-15-x-25-3-n-the-cause-of-leaf-perforations-of-lettuce-m-violae-pass-saccquot-discoloration-of-the-host-slight-2yy-acervuli-nvunerous-scattered-small-fquotquotquot-conidia-curved-or-straight-15-18-x-yk-y-j-5-6-ii-septum-usually-excentric-t-small-spots-are-produced-on-violet-fig-374marssonia-violse-spores-and-conidiophores-leaves-PG45MK.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. 556 THE FUNGI WHICH CAUSE PLANT DISEASE CI^N ' 100-120 /I, or by confluence larger; I /vO conidia abundant, clavate or wedge- ^ shaped, 11-15 x 2.5-3 n. The cause of leaf perforations of lettuce. M. violae (Pass.) Sacc."' Discoloration of the host slight; ^ ^^-^ 2^:^^yy acervuli nvunerous, scattered, small; ,,^ (f""" â conidia curved, or straight, 15-18 x yK^;;;-y^ J 5-6 ii, septum usually excentric. T, â,, ., , Small spots are produced on violet Fig. 374.âMarssonia violse. Spores and conidiophores. leaveS. Stock Photo")
RMPG45MK–. The fungi which cause plant disease . Plant diseases; Fungi. 556 THE FUNGI WHICH CAUSE PLANT DISEASE CI^N ' 100-120 /I, or by confluence larger; I /vO conidia abundant, clavate or wedge- ^ shaped, 11-15 x 2.5-3 n. The cause of leaf perforations of lettuce. M. violae (Pass.) Sacc."' Discoloration of the host slight; ^ ^^-^ 2^:^^yy acervuli nvunerous, scattered, small; ,,^ (f""" â conidia curved, or straight, 15-18 x yK^;;;-y^ J 5-6 ii, septum usually excentric. T, â,, ., , Small spots are produced on violet Fig. 374.âMarssonia violse. Spores and conidiophores. leaveS.
RMRDA7H3–. Injurious insects : how to recognize and control them . Insect pests; Insect pests. 308 FESTS OF ORCHARD AXD SMALL FRVITS stop to the insect. Or the fohage may be sprayed mth arsenate of lead as soon as the leaves are out. The Pear-leaf Blister-mite (Eriophyes pyri Pgst.) The leaves of apple and pear often are infested with a species of mite that burrows into the tissues of the leaf, causing a characteristic dis- coloration and swelling. Spots show in the upper leaf surface, at. Fig. 4/0.—Work of the Pear-leaf Blister-mite. Original. first redcUsh, but later turning broTi. At each spot the
RMPFWR83–. A manual for the study of insects. Insects. 250 THE STUDY OF INSECTS, mines. In some of the blotch mines the epidermis of one side of the leaf is thrown into a fold by the growth of the leaf; these are tentiform mines. In addition to peculiarities in shape many mines are marked by characteristic lines or spots composed of the droppings of the larva. The following species will serve to illustrate the habits of these remarkable insects. The White-blotch Oak-leaf Miner, Lithocolletis hamadrya- della (Lith-o-col-le^tis ha-mad-ry-a-deria).—This little miner infests the leaves of many different sp
RMRDWE9B–. Elementary botany. Botany. 324 ECO LOG V. only a short branch of the mycelium, nutritive substances are taken by the fungus from the protoplasm or cell-sap of the carnation. From here it passes to the threads of the mycelium. These in turn supply food material for the development of the dark brown gonidia, which we see form the dark- looking powder on the spots. Many other fungi form haustoria, which take up nutrient matters in the way described for the carnation rust. In the case. Fig. 427. Cell from carnation leaf, showing haustoriuin of rust mycelium grasping the nucleus of the host. A, h
RMPG4F5R–. Diseases of economic plants . Plant diseases. DISEASES OF ECONOMIC PLANTS fungi have been isolated from these spots/ some of them may sustain a causal relation to the disease. Whatever the actual causal fungus may be, these spots are all, or nearly all, of fungous ori- gin and are amenable to preventive spraying with Bordeaux mixture. The first of three or four appUcations should be given with the opening of the leaf buds. Illosporiose, leaf spot (Illosporium malijolio- rum Shel.). — This is said by Sheldon- to be the cause of much of the defoliation of apple or- chards in West Virginia and
RMRDE3EB–. Diseases of economic plants . Plant diseases. 154 DISEASES OF ECONOMIC PLANTS In a severe outbreak which is necessary to attract atten- tion to the disease the leaves first become covered with small dark brown spots, change to yellow, and soon fall. By the time the fruit has ripened practically all of the. Fig. 66. — Anthr^icnoso of white currants. After Clinton. leaves may be lost. Upon the leaf stalks, also upon the fruit, stems, and canes, the disease appears as little black sunken spots. On theberries the spots are circular and black, much resembling fly specks. The causal fungus probabl
RMPG3NT4–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. disease is distinguished from the leaf spot by smaller spots more colored when young and more nearly circular. They are also less clearly defined on the under surfaces. The blight also attacks the fruit. In this case the spots are at first red but later darker in color. The drying of the surface layers accom- panying the effects of this disease may cause a cracking very much as in the case of pear scab. The fungus. The larger spots of the leaf blight will generally show at the time
RMRDAB74–. A text-book of botany for secondary schools. Botany. Fig. 36.—Leaves of the Califorman pitcher- plant, showing the twisted and winged pitcher, the overarching hood with trans- lucent spots, and the fish-tail appendage to the hood.—After Kerner. Fig. 37.—Leaf of Nepenthes, shov.-- ing the blade-like base, the ten- dril portion, and the terminal pitcher with its lid. — After Gray. elaborate pitcher with a lid (Fig. 37). There is the same sweetish secretion at the rim of the pitcher, and the same accumulation of water within as in the ordinary pitcher- plants. (5) Leaves of sundews.—The sundews
RMPG3NTA–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 366 FUNGOUS DISEASES OF PLANTS. disease is distinguished from the leaf spot by smaller spots more colored when young and more nearly circular. They are also less clearly defined on the under surfaces. The blight also attacks the fruit. In this case the spots are at first red but later darker in color. The drying of the surface layers accom- panying the effects of this disease may cause a cracking very much as in the case of pear scab. The fungus. The larger spots of the leaf blight
![. Illustrated key to the wild and commonly cultivated trees of the northeastern United States and adjacent Canada [microform] : based primarily upon leaf characters. Trees; Trees; Arbres; Arbres. Fig. 192. Swecl Bay. Fi'r. 193. Cucumber Tree. hairy beneath. Flowers broad bell-shaped, white (with purple spots at the base), about 6 inches long. Ky. southward. (Fig. 194.) Great-leaved Magnolia, Great- leaved Umbrella Tree, Magnolia macro- phylla Michx.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appea Stock Photo](https://c8.alamy.com/comp/REMJGH/illustrated-key-to-the-wild-and-commonly-cultivated-trees-of-the-northeastern-united-states-and-adjacent-canada-microform-based-primarily-upon-leaf-characters-trees-trees-arbres-arbres-fig-192-swecl-bay-fir-193-cucumber-tree-hairy-beneath-flowers-broad-bell-shaped-white-with-purple-spots-at-the-base-about-6-inches-long-ky-southward-fig-194-great-leaved-magnolia-great-leaved-umbrella-tree-magnolia-macro-phylla-michx-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appea-REMJGH.jpg ". Illustrated key to the wild and commonly cultivated trees of the northeastern United States and adjacent Canada [microform] : based primarily upon leaf characters. Trees; Trees; Arbres; Arbres. Fig. 192. Swecl Bay. Fi'r. 193. Cucumber Tree. hairy beneath. Flowers broad bell-shaped, white (with purple spots at the base), about 6 inches long. Ky. southward. (Fig. 194.) Great-leaved Magnolia, Great- leaved Umbrella Tree, Magnolia macro- phylla Michx.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appea Stock Photo")
RMREMJGH–. Illustrated key to the wild and commonly cultivated trees of the northeastern United States and adjacent Canada [microform] : based primarily upon leaf characters. Trees; Trees; Arbres; Arbres. Fig. 192. Swecl Bay. Fi'r. 193. Cucumber Tree. hairy beneath. Flowers broad bell-shaped, white (with purple spots at the base), about 6 inches long. Ky. southward. (Fig. 194.) Great-leaved Magnolia, Great- leaved Umbrella Tree, Magnolia macro- phylla Michx.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appea
RMPG4EHC–. Diseases of economic plants . Plant diseases. 304 DISEASES OF ECONOMIC PLANTS. Fig. 133.—Tobacco leaf showing leaf spot (cercosporose). After Conn. Exp. Sta. The disease was first described hy Sturgis' from specimens sent from South Carolina. It was then very destructive, practically ruining the crop. A damage of $1000 to one crop alone was noted. It has since con- tinued as a troublesome pest. The use of Bordeaux early in the season is per- missible and advanta- geous. White speck {Macro- sporium tabacinum Ell. & Ev.). — White speck con- sists of small, circular spots, rusty red or brow
RMRDFE02–. Manual of tree diseases . Trees. 228 MANUAL OF TREE DISEASES tinguished from one another except by the microscopic chap- acters of the black fruiting-bodies which are just visible to the unaided eye. The mycelium of both fungi causes powdery white, more or less definite spots on the imder sides of the leaves. The life histories and control of powdery mildew fungi are discussed on page 37. Leaf-Bught Caused by Glceosporium sp. This leaf-blight has been observed on Norway maple (Acer platanoides) in Connecticut, New York and Virginia. No studies have been made on the disease and but little is
RMPG4E7P–. Diseases of economic plants . Plant diseases. U-2 DISEASES OF ECONOMIC PLANTS MAPLE Leaf spot, phyllostictose {Phyllosticta acericola C. & E.)- — A large proportion of the leaf may become involved, causing premature defoliation which materially lessens the. Fig. 193. — Maple tar spot. After Heald. value of the tree for ornament or shade. The silver maples are especially susceptible, and their sale has thereby been reduced. The leaf spot was first noted in 1874 and is dis- tributed throughout the United States. The blackish, subcircular spots as they enlarge change to brown and later. Ple
RMRDJ685–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 34° FUNGOUS DISEASES OF PLANTS very pronounced shot-hole effect. Varieties of Primus americana are frequently free from this fungus. Where a species or variety is subject to shot-hole diseases a shot- hole effect may also be produced upon the leaves by spraying with any substance injurious to the leaf. When the leaves are so severely injured that the spots coa- lesce, the large irregular pieces may fall out in the same manner as just indicated. In any case the effects of shot-hole
![. Diseases of truck crops and their control . Vegetables. ^'' ^''"%.. X â s, d. Fig. 69. Celery Diseases. fl. Septoria leaf spot on leaf, h. Septoria leaf spot on leaflet, c. Septoria lesions on celery seed, d. Septoria spots showing pycnidial bodies, e. cross section showing pyncidium and pycnospores of Septoria peiroseltni (a, c, and e after Coons and Levin).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Taubenhau Stock Photo](https://c8.alamy.com/comp/PG4CAF/diseases-of-truck-crops-and-their-control-vegetables-quot-x-s-d-fig-69-celery-diseases-fl-septoria-leaf-spot-on-leaf-h-septoria-leaf-spot-on-leaflet-c-septoria-lesions-on-celery-seed-d-septoria-spots-showing-pycnidial-bodies-e-cross-section-showing-pyncidium-and-pycnospores-of-septoria-peiroseltni-a-c-and-e-after-coons-and-levin-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-taubenhau-PG4CAF.jpg ". Diseases of truck crops and their control . Vegetables. ^'' ^''"%.. X â s, d. Fig. 69. Celery Diseases. fl. Septoria leaf spot on leaf, h. Septoria leaf spot on leaflet, c. Septoria lesions on celery seed, d. Septoria spots showing pycnidial bodies, e. cross section showing pyncidium and pycnospores of Septoria peiroseltni (a, c, and e after Coons and Levin).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Taubenhau Stock Photo")
RMPG4CAF–. Diseases of truck crops and their control . Vegetables. ^'' ^''"%.. X â s, d. Fig. 69. Celery Diseases. fl. Septoria leaf spot on leaf, h. Septoria leaf spot on leaflet, c. Septoria lesions on celery seed, d. Septoria spots showing pycnidial bodies, e. cross section showing pyncidium and pycnospores of Septoria peiroseltni (a, c, and e after Coons and Levin).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Taubenhau
RMRDD7NE–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. FiG. 194.—PhrftgniidiiiTn sttbcwticium on a Rose leaf. The black spots are teleutospore-patches on the uuder- surface of the leaf. (v. Tubeuf deL) Fig. 193.— Tfipkragmium ulmai-iac on Spiraea Ulmai-ia. Germinating teleuto- spore, with promycelia and ^poridia. (After Tulasne.) teleutospores are produced in loose patches. The aecidial patches have no covering, but are surrounded by club-shaped paraphyses. The genus fr
RMPG3T9X–. Manual of fruit diseases . Fruit. APPLE DISEASES 49 two characters serve to distinguish soft-rot from black-rot and other apple-rots. The disease on the leaves is noticeable from a time shortly • following their unfolding to the end of the summer. One to ^-:V. Fig. 12. — Leaf-spot of apple. several spots occur on a single leaf; in the latter case the lesions are scattered or grouped (Fig. 12). On the upper surface the first evidence of this leaf-spot is a minute, purplish speck, which soon enlarges until it attains a diameter of about one- eighth of an inch. The spot later becomes yellowish
RMRDCX75–. Manual of fruit diseases . Fruit. PEAR DISEASES 343 by brown depressed scars. In the late spring dark-brown, wedge-shaped horns, which later become yellowish, are devel- oped. Cause. The eastern pear rust is caused by the fungus Gym7iospo- rangium globosum. Like other rust fungi it has two distinct host plants, the pear and the red cedar. If the spots of an affected pear leaf be examined, the upper surface will show small black fruiting bodies known as pycnia. These do not function in the life-history of the pathogene so far as is known, but are mentioned for their diagnostic value. They are
![. The fungi which cause plant disease . Plant diseases; Fungi. 522 THE FUNGI WHICH CAUSE PLANT DISEASE The cause of leaf spots of tomato. It was noted in New Jersey about 1893»" and in Ohio in ISQG.^'^ It is one of the serious tomato pests. S. lactucae Pass.^^"* Spots irregular, brownish, angulate, sometimes destroying the entire leaf, pycnidia minute, punctiform, scattered, 90 n in diameter, conidia filiform, straight or curved, 25- 30 X 1.7-2 M- On lettuce. S. consimilis E. & M.'* Distinguishable from the preceding by the more indefinite spots, slightly larger pycnidia (90-100 Stock Photo](https://c8.alamy.com/comp/PG45P5/the-fungi-which-cause-plant-disease-plant-diseases-fungi-522-the-fungi-which-cause-plant-disease-the-cause-of-leaf-spots-of-tomato-it-was-noted-in-new-jersey-about-1893quot-and-in-ohio-in-isqg-it-is-one-of-the-serious-tomato-pests-s-lactucae-passquot-spots-irregular-brownish-angulate-sometimes-destroying-the-entire-leaf-pycnidia-minute-punctiform-scattered-90-n-in-diameter-conidia-filiform-straight-or-curved-25-30-x-17-2-m-on-lettuce-s-consimilis-e-amp-m-distinguishable-from-the-preceding-by-the-more-indefinite-spots-slightly-larger-pycnidia-90-100-PG45P5.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. 522 THE FUNGI WHICH CAUSE PLANT DISEASE The cause of leaf spots of tomato. It was noted in New Jersey about 1893»" and in Ohio in ISQG.^'^ It is one of the serious tomato pests. S. lactucae Pass.^^"* Spots irregular, brownish, angulate, sometimes destroying the entire leaf, pycnidia minute, punctiform, scattered, 90 n in diameter, conidia filiform, straight or curved, 25- 30 X 1.7-2 M- On lettuce. S. consimilis E. & M.'* Distinguishable from the preceding by the more indefinite spots, slightly larger pycnidia (90-100 Stock Photo")
RMPG45P5–. The fungi which cause plant disease . Plant diseases; Fungi. 522 THE FUNGI WHICH CAUSE PLANT DISEASE The cause of leaf spots of tomato. It was noted in New Jersey about 1893»" and in Ohio in ISQG.^'^ It is one of the serious tomato pests. S. lactucae Pass.^^"* Spots irregular, brownish, angulate, sometimes destroying the entire leaf, pycnidia minute, punctiform, scattered, 90 n in diameter, conidia filiform, straight or curved, 25- 30 X 1.7-2 M- On lettuce. S. consimilis E. & M.'* Distinguishable from the preceding by the more indefinite spots, slightly larger pycnidia (90-100
RMRDD8TD–. Diseases of economic plants . Plant diseases. VEGETABLE AND FIELD CEOPS 287 Blotches' appear upon the leaves, first as small, moist, watery areas, associated with slight local wilting, followed soon by the appearance upon either side of tlie leaf of very small brown acervuli. The spots then change to gray and dry up. The disease spreads rapidly from plant to plant and is very destructive both under glass and in the open, rendering the plant unfit for use. White smut (Entyloma El- lisii Halst.). — The attacked plants are unmarketable, due to lack of uniform green ('olor and the presence of jK
RMPG3NY1–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECTI 347 Phyllosticta maculicola Hals.1 is the cause of a very common leaf spot of several species of Dracaena and Cordyline. The spots are characterized by pale centers an'd reddish or purplish borders. The disease is sometimes severe in greenhouses where it has long been allowed to proceed unchecked. It is, however, readily pre- vented by spraying with potassium sulfide solution. Phyllosticta Ampelopsidis Ell. & Mart, is perhaps closely related to the fungus causi
![. Minnesota plant diseases. Plant diseases. 364 Minnesota Plant Diseases.. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against Stock Photo](https://c8.alamy.com/comp/RDE33M/minnesota-plant-diseases-plant-diseases-364-minnesota-plant-diseases-fic-194black-rot-of-apple-after-clinton-fruit-when-attacked-turns-at-first-a-reddish-brown-but-later-be-comes-blaclf-on-attacked-portions-of-the-tree-the-fungus-pro-duces-its-spores-it-is-an-quotimperfectquot-fungus-and-produces-spores-in-small-capsules-which-appear-on-the-leaf-twig-or-fruit-spots-as-tiny-black-warts-these-open-to-the-exterior-by-minute-pores-through-which-the-spores-which-are-cut-off-of-threads-lin-ing-the-interior-of-the-capsule-are-thrown-out-the-treatment-which-is-used-against-RDE33M.jpg ". Minnesota plant diseases. Plant diseases. 364 Minnesota Plant Diseases.. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against Stock Photo")
RMRDE33M–. Minnesota plant diseases. Plant diseases. 364 Minnesota Plant Diseases.. Fic. 194.—Black rot of apple. After Clinton. fruit, when attacked, turns at first a reddish brown but later be- comes blaclf. On attacked portions of the tree the fungus pro- duces its spores. It is an "imperfect" fungus and produces spores in small capsules, which appear on the leaf, twig or fruit spots as tiny black warts. These open to the exterior by minute pores through which the spores, which are cut off of threads lin- ing the interior of the capsule, are thrown out. The treatment which is used against
RMPFXE0R–. Insects injurious to fruits. Illustrated with four hundred and forty wood-cuts. Insect pests. ATTACKING THE LEAVES. 91 Fig. 89.. shown somewhat magnified; also the chrysalis, which is about the natural size. Besides consuming the leaves, this leaf- roller is very fond of gnawing the skin of the young fruit, and such abraded spots soon become brown and rusty, and sometimes crack. When mature, the larva lines the inner surface of its dwelling-place with a web of silk, and then changes to a chrysalis of a dark-brown color. (See Fig. 89.) Towards the end of June, or early in July, with the help
RMRDE3CH–. Diseases of economic plants . Plant diseases. SMALL FRUITS 171 side may cause distortion, cracking, and exposure of the seeds. Upon the leaves the dead spots are usually bordered by a fine black line, and as the leaf grows the dead tissue of the spot may rupture irregularly. Badly anthracnosed canes must be cut out and burned, and cleansing sprays should be used. Necrosis {Fusicoccum viticolum Reddick). — This disease is said by Reddick ^ to cause perhaps 50 per cent of the death of vines usually attributed to root worm or other causes. It has been noted in New York, Ohio, Georgia, Indi- ana
RMPG0GF7–. Diseases of greenhouse crops and their control . Vegetables; Plant diseases; Plant diseases. Fig. 27. Lettuce Diseases. o. Drop (after Humphrey), b. Septoria leaf spot, c, same as &. but older spots, d. pycnida, e. pycniospores (af- ter Selby).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Taubenhaus, Jacob Joseph, 1884-1937. New York : E. P. Dutton
RMRDEG6M–. Diseases of economic plants . Plant diseases. 474 DISEASES OF ECONOMIC PLANTS nearly so. The larger spots are a centimeter or more in diameter, and they frequently coalesce so as to nearly cover whole leaflets. With age the spots turn gray at the centers, at which part the leaf dies. They also become more regular in outline. Fig. 201. — Rose mildew ; diseased and healthy shoots. Original. than in their earlier stages. Portions of the leaflets out- side of the area actually spotted often turn yellow, and the diseased leaflets fall off prematurely. Thus the beds be- neath diseased plants are o
RMPFXE0M–. Insects injurious to fruits. Illustrated with four hundred and forty wood-cuts. Insect pests. shown somewhat magnified; also the chrysalis, which is about the natural size. Besides consuming the leaves, this leaf- roller is very fond of gnawing the skin of the young fruit, and such abraded spots soon become brown and rusty, and sometimes crack. When mature, the larva lines the inner surface of its dwelling-place with a web of silk, and then changes to a chrysalis of a dark-brown color. (See Fig. 89.) Towards the end of June, or early in July, with the help of some little thorns on the hinder
RMRDWD0W–. Plants and their ways in South Africa. Botany; Botany. 230 Plants and their Ways iti South Africa Maiden Hair and most of the South African ferns have short creeping stems, but Cyathea of Natal, and the beautiful Hemitelia, of Knysna and the West, have woody stems which grow to quite a height. On the under side of most fern leaves you will find brown spots. Some people cut their ferns down and burn them when they find them there, thinking that they are scale insects. When the spots get quite brown, gently shake a leaf over white paper. A brown dust will appear on the paper. These. Fig. 204.—
RMPG3MM0–. Manual of fruit diseases . Fruit. 378 MANUAL OF FRUIT DISEASES Symptoms. The disease appears in midsummer but is most abundant in fall. Only the leaves are commonly affected; fruits or other parts of the plum rarely show rust-lesions. On the lower surfaces rust-pustules are found (Fig. 110); these are light-brown, small, round and somewhat powdery. They are scattered, or they may be so numerous as to practically cover the leaf (Fig. 110). The develop- ment of these pustules is preceded by the formation of yellowish spots. Later the pustules, or sori, to be observed on the leaves are dark-bro
RMRDDWJ6–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. PERONOSPORA. 133 oospore-coat (oospores of P. viciae have a coat with a regular net- work). It occurs on stems, leaves, and petioles of clovers, lucerne and other Papilionaceae, often with disastrous effect. P. sparsa, Berk. (Britain and U.S. America). This parasite on the rose was first observed in England. It injures indoor roses, causing a fall of the leaf, preceded by the appearance of lilac-coloured spots which
RMPG4EMD–. Diseases of economic plants . Plant diseases. 226 DISEASES OF ECONOMIC PLANTS CELERY Leaf spot, early blight, cercosporose {Cercospora Apii Ft.). — The leaf spot is common in both Europe and America, constituting probably the most destructive disease to which the celery plant is subject. It is known from. Fig. 106. —• Cauliflower affected with black rot, (Pseudomonose). Original. Colorado to New Jersey. In Florida in 1906 it is said to have injured 80 per cent of the crop. The crop is largely reduced, and the unsightUness of the spots injures the salability of the product. The spots appear f
RMRDT9PK–. The Peanut, the unpredictable legume; a symposium. Peanuts; Peanuts. PEANUT DISEASES 273 At maturity early leafspots are reddish-brown to black, and lighter brown to tan with less distinct halos on the lower surface. Late leafspots are soon very dark brown to almost black on both surfaces. Cushions of conidiophores are formed at first only on the upper sur- face in early leafspot, but sometimes form on the lower surfaces of older spots. In late leafspot, however, conidiophores are almost always confined to the lower leaf surfaces, and the cushions of tufts usually are in plainly visible conc
RMPG14T2–. Manual of tree diseases . Trees. CHAPTER XIII BUTTERNUT DISEASES The butternut (Juglans cinerea) throughout its range in eastern and central United States is subject to a few diseases only. The most important of these is the leaf-spot, which also affects walnut and hickory. This disease often causes a part or all of the leaves to fall from the tree in midsummer. Oc- casionally the brown checked wood-rot and common white wood-rot are found in butter- nut. Leaf-Spot Caused by Marssonia juglandis (Lib.) P. Magnus This is the common leaf- spot of butternut and walnut. Irregular dark brown spots
RMRDRBYK–. Natural history. For the use of schools and families. Zoology. COLBOPTEEA, OE SHEATH-WINGED INSECTS. 247 being more effective in this respect than the Beetles themselves. They are about half an inch long, of a bluish color with four or six yellow spots, and are seen creeping along branches and leaves in search of the plant-lice. After living in the larva state for a fortnight, they fasten themselves on some leaf, cast off their skins, spin a cocoon, and, after a fortnight's sleep, issue as Lady- birds. [ One of the species, the North- ern Lady-bird, is seen in Fig. 190. It is found chiefly o
RMPG4EMX–. Diseases of economic plants . Plant diseases. 224 DISEASES OF ECONOMIC PLANTS ease appears and often enough thereafter to cover growing parts, is recommended.' Phyllostictose (Phyllostida cucurbitacearum Sacc.) • — Th is leaf spot has been destructive in several states, notably so in New Jersey and Ohio. The spots are light colored and the fungus appears as a pycnidium in their centers. Cladosporiose. See cucumber. CARROT Soft rot, bacillose (Bacillus carotovorus Jones ^).— In Ver- mont serious loss from rotting of carrots was reported to the Experiment Station in 1898. Investigation by Jone
RMRDDY69–. Cabbage, cauliflower and allied vegetables : from seed to harvest . Vegetable gardening; Cabbage; Cauliflower. 122 FUNGOUS DISEASES. are a sure sign of the black rot, showing that the germs have already passed from the leaves into the stems. If the stem of a healthy cabbage leaf be cut across, these vessels are seen forming faint yellowish spots in the interior, in marked contrast to the black spots seen in the badly diseased leaf. In case of .V. Fig. j6—Healthy Cabbage Leaf, Showing Water Beads Along the Margin. leaves which are but partly diseased, only those ves- sels leading into the dis
RMPG3NBF–. Manual of fruit diseases . Fruit. 338 MANUAL OF FRUIT DISEASES was observed several years ago that the Bosc, Sheldon, Seckel, Anjou, Bartlett and others are injured more than the Flemish, Clairgeau and Duchess. The Kieffer, Lawrence and Mount Vernon are relatively resistant to leaf-spot. In the nursery, budded pear-stock, after the first year, may show occasional lesions, but budded stock of two or more years is often badly injured late in the simamer. Symptovis. Only the leaves are affected. The mature spots are recog- nized by their well-defined angular margins and their grayish white cent
RMRDCY42–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 488 FUNGI IMPERFECTI. Faded spots appear on the leaves, becoming later greyish brown dotted over with minute black points, the couidial patches.' C. ampelinum Cav. causes little dry spots on the leaves of vine, fre- quently in such numbers that the whole leaf dries up. C. kentjae Hals, attacks palm-seedlings so that their leaves do not unfold. C. cyclameneae Hals, occurs on Cydamen. Scoleco-Allantosporae. Cylindrosp
RMPG3GXC–. An illustrated descriptive catalogue of the coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana : with bibliography and descriptions of new species . Beetles. THE LEAF BEETLES. 1183 21S4 (693<!). CEdionychis fimbbiata Forst, Nov. Sp. Ins., I, 1771. 25. Oblong-oval, moderately convex, feebly shining. Dull reddish-yellow; thorax with five piceous spots, usually more or less confluent; elytra with only a narrow sutural line black, or with three piceous stripes, with inter- grades; femora and under surface, except the metasternum, reddish-yellow; antennae, tibiae a
RMRE2D94–. Plants and their uses; an introduction to botany. Botany; Botany, Economic. Fig. S2, II.—Turban Sqiui>li {('nrurhita inoxuna, var., Gourd Family, CucurbitacecE). Leaves and fruit, I. Fruit greenish, yellowish, or reddish. (Vilmorin.). Fig. 83.—Winter Crook-neck Squash (Cucurhito moschata, Gourd Family. Cucurhitacr(£). Leaf. Flowering l»ranch. Pistillate flower. Staruinate flower. Staminate flow-er bud, showing leaf-like sepals. (Nicholson.)— Plant similar to the preceding species, but soft-hairj- and the leaves often with silvery spots; fruit variously colored.. Please note that these ima
RMPFXK7A–. The encyclopedia of practical horticulture; a reference system of commercial horticulture, covering the practical and scientific phases of horticulture, with special reference to fruits and vegetables;. Gardening; Fruit-culture; Vegetable gardening. Fig. 1. Beet Leaf Hopper, la, Adult of E. tenella; lb, Nymph; 2, Adult of E. scitula. ed or elongated in shape; whitish or pale yellow in color with a large tuft of white flocculence covering the posterior end of the body. The legs, antennae, and spots on the top of the head are brown. The winged lice are a little larger, more elon- gated and muc
RMRDFE3W–. Manual of tree diseases . Trees. BUCKEYE DISEASES 119 defoliation results in retanHnc; tlic growth of the trees and making tliem more susceptible to winter-injury. Si/mptoms. The lesions develop on the leaflets and petiole. AMien first evident, the spots are irregular in outline, slightly dis- colored and water-soaked in appearance. Later the center of the spot becomes red- dish brown and is sur- rounded by a yellowish zone which blends into the green of the healthy part of the leaf. Finally, the entire affected area turns brown and becomes dried and brittle (Fig. 14). The spots may be small
RMPG4E78–. Diseases of economic plants . Plant diseases. TBEES AND TIMBER 449 causes a stoppage of the water supply to the more distant portions of the leaf, resulting in dead areas. Dead twigs should be pruned out, and infected material col- lected and burned. Spraying with Bordeaux mixture may be practiced if the expense is warranted. Powdery mildew. See oak. BLACK WALNUT Anthracnose, Gnomoniose {Marsonia juglandis (Lib.) Sacc. of Gnomonia juglandis). — Conspicuous brown spots, 2-4 mm. in diameter, appear upon the leaflets, which soon yellow and fall. Upon the lower sides of the leaf spots are small,
RMRE2NK8–. Elementary botany. Botany. HOW PLAXTS OBTAIN FOOD. 87 of these plants wliich are known as parasitic fungi. Tlie plant at whose expense tliey grow is called the ^'jLosiS' One of these parasitic fungi, which it is quite easy to obtain in green- houses or conservatories during tlie autumn and wdnter, is the carnation rust {C'7-o}fiyt-s cayvophvilinus), since it Vjreaks out in rust)' dark Vjrown patches on the leaves and stems of the carnatinn (see fig. 75). If we make thin cross sections through one of these spots on a leaf, and place them for a Fig. 76. Several teleutospores, sho^^'ing the va
RMPG3R80–. Manual of fruit diseases . Fruit. Fig. 41. — Coryneum-blight disease on apricot fruits.. Fig. 42. - Coryneum-blight disease on apricot leaves. been recorded from Australia as early as 1882, and an epiphytotic was reported from Algeria in 1904. Small, reddish spots at first with light centers then becoming dark-green to black, are produced on the fruits (Fig. 41). The foliage is spotted; the affected areas are brown, but soon these fall away, leaving a shot-hole effect in the leaf (Fig. 42). Fruit-buds are sometimes killed as a result. Please note that these images are extracted from scanned
RMRDE16N–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. DETAILED ACCOUNT OF SPECIFIC PLANT DISEASES 559 black or very dark brown at first, but changing to a lighter shade, as the spots grow older. The first diseased part of the leaf looks as if water- logged, and in a few days, the diseased part of the leaf peripheral to the central spot fades, or bleaches, to a yellow, or grayish-white. Here the disease may stop and the plants recover, the diseased areas separate from the healthy tissue and fall out leaving holes in the leaves. The disease
RMPG3H1G–. An illustrated descriptive catalogue of the coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana : with bibliography and descriptions of new species . Beetles. THE LEAF BEETLES. 1157 2142 (HSdS). Calliqkapha scalaeis Jjec, Ann. Lye. Nat. Hist., I, 1824, 173. Oval, convex. Dark metallic green, shining; elytra cream.v white with a broacl, greenish, common sutural stripe, which projects three short spurs each side, and each with a large, curved humeral lunule double to near middle and enclosing a round greenish spot; behind the lunule 12 to l.i small greenish spots;
RMRE36Y5–. The British rust fungi (Uredinales) their biology and classification. Rust fungi. GYMNOSPORANGIUM 305 JEcidiospores. iEcidia clustered on yellow or orange thick- ened spots on the leaves, fruits, and stems, cylindrical, up to. Fig. 230. G. clavariaeforme, .^cidia (Eoeatelia) on leaf, fruit and branch of Hawthorn (reduced); a, peridium x 16. The fruit and gall on branch are shown as tliey appear when the peridia are old and the mass looks some- what like a honey-comb. 2| mm. high, fimbriate above, at length lacerate to base, pale- brown ; spores verruculose, brownish, about 28—30 fi; pores 8—
RMPFX8W3–. A manual for the study of insects. Insects. COLEOPTERA. 579 and later gnawing holes into the leaves (Figs. 705 and 706). In May and June the brown, sluggish larvae may also be found feeding upon the upper surface of the leaves. The full-grown larva is chestnut-brown, marked with black spots. The beetles can be destroyed in early spring by jarring them from the vines onto a sheet wet with kerosene ; use for this purpose a piece of sheeting several yards long, with a stick fastened to each end so that it can be easily moved from vine to vine. The Wedge-shaped Leaf-beetles,— These insects are c
RMRDCXGF–. Manual of fruit diseases . Fruit. 238 MANUAL OF FRUIT DISEASES Symptoms. On the upper surface of the leaf the first signs of downy-mildew are in the form of small greenish yellow indefinite spots, the margins of which gradually merge into the darker green of. Fig. 61. — Downy-mildew on lower surface of grape-leaf. the leaf. In a short time there appears within the spot a net- work of small, reddish brown lines, the discolored smaller veins. These lines become more pronounced until the whole diseased portion is brown, dry and brittle, and eventually cracked. These symptoms apply particularly
RMPG4ETA–. Diseases of economic plants . Plant diseases. SMALL FRUITS 181 STRAWBERRY Leaf spot {Sphaerella fragarix (Tul.) Sacc). — The most conspicuous disease of the strawberry, one nearly al- ways present to some extent on both wild and culti-. FiG. 78. — Strawberry leaf spot. After Freeman. vated varieties, is known by the presence of small 4-6 mm. purple or red bordered spots upon the leaves, the older spots bearing white or ashen centers. Late in the development of the spots the hyphae of the causal fungus are barely visible in these centers with a good hand lens. The spots, when numerous, may co
RMRE2MB6–. Practical botany. Botany. THE STEM AND THE LEAF (i7 with sleet (Fig. 28). These may be blown over erustcd snow or floated along by brooks or rivers near which the trees grow, and doubtless often lodge in spots where they take root and grow into new trees. 61. Aerial, floating, and submerged leaves of water plants. Many plants which grow rooted under water have only aerial leaves. To this class belong many arrowheads, tlie cat-tails.. Fig. 55. Victoria regia and other tropical and sub-tropical water lilies at the nurseries of Henry A. Dreer, Philadelphia The Victorias have the largest known f
RMPG3YRW–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 204 FUNGOUS DISEASES OF PLANTS. Fig. 77 b. Alfalfa defoliated by the Leaf Spot Fungus. (Photo- graph by H. H. Whetzel) Small sooty brown or black spots about -X- inch in diameter are 1 D produced, first evident on the upper surfaces of the leaves (Fig. 78). In these spots there appear later in the season the relatively simple, sessile apothecia, which are formed beneath the epidermis and break through at maturity. The spots are often very numer- ous, causing defoliation of many of
RMRDE4Y7–. The fungi which cause plant disease . Plant diseases; Fungi. Fia. 416.—Sporodesmium antiquum. After Sac- caxdo. S. exitiosum var. solani Schenck is reported as the cause of a potato disease. S. solani-varians Yanha is the cause of potato disease in Europe, the foliage bearing brown spots and finally dying in a manner resembling death caused by Phytophthora. Cladosporium and pycnidial forms are said to exist. S. mucosum Sacc. was reported by Ader- holt on cucumber fruit and leaves causing disease. S. scorzonerae Aderh. causes a salsify stem and leaf disease.'^* Other parasitic species are: S.
RMPG14PD–. Manual of tree diseases . Trees. CHAPTER XVII ELM DISEASES. Fig. 21, — Leaf-spot of elm. 152 The elms (Ulmus) are common forest and orna- mental trees east of the Rocky Moimtains. They are exceptionally free from specific diseases caused by parasites. Wound-rots and slime-flux are common in the crotches of the large limbs. Chaining is often necessary to prevent split- ting at the crotches. Leaf-Spot Caused by Gnomonia idmea (Sace.) Thiim. This is the most com- mon of the leaf-spot dis- eases of elm. In wet seasons, the spots become so abundant that defolia- tion results. The fungus causing t
RMRE3AG7–. Introduction to botany. Botany. THE STE:^! AXD THE LEAF trees grown in woodlands, where they stand moderately close together. In some trees â such as the so-called snap willows, the cotton^^â OGd, and the large-toothed aspen â live twigs fall evy freely during windsti iniis and snowstorms, and when the tree is loaded with sleet. These twigs may be blown over crusted snow or floated along by brooks or rivers near by, and often lodge m spots where they take root and grow into new trees. 77. Leaves of water plants. Water plants with aerial leaves, like the cat-tails and pickerel weeds, are per
![. Minnesota plant diseases. Plant diseases. ;74 Minnesota Plant Diseases. occurs on other more or less closely related plants. The fungus mycelium gains entrance to the plant in the spring and first pro- duces cluster cups. These are followed by the summer spores, throughout the summer months, forming small red-brown patches. ]"lG. 199.—Leaf rust of roses. The cluster-cup stage on the stems and leaves. On left is a stem distorted by the cluster-cup cushions. Photograph by H. Cuzner upon large, dark, red-brown spots in great abundance, on the lower surface of the leaves. The summer-spores Stock Photo](https://c8.alamy.com/comp/PG4EJA/minnesota-plant-diseases-plant-diseases-74-minnesota-plant-diseases-occurs-on-other-more-or-less-closely-related-plants-the-fungus-mycelium-gains-entrance-to-the-plant-in-the-spring-and-first-pro-duces-cluster-cups-these-are-followed-by-the-summer-spores-throughout-the-summer-months-forming-small-red-brown-patches-quotlg-199leaf-rust-of-roses-the-cluster-cup-stage-on-the-stems-and-leaves-on-left-is-a-stem-distorted-by-the-cluster-cup-cushions-photograph-by-h-cuzner-upon-large-dark-red-brown-spots-in-great-abundance-on-the-lower-surface-of-the-leaves-the-summer-spores-PG4EJA.jpg ". Minnesota plant diseases. Plant diseases. ;74 Minnesota Plant Diseases. occurs on other more or less closely related plants. The fungus mycelium gains entrance to the plant in the spring and first pro- duces cluster cups. These are followed by the summer spores, throughout the summer months, forming small red-brown patches. ]"lG. 199.—Leaf rust of roses. The cluster-cup stage on the stems and leaves. On left is a stem distorted by the cluster-cup cushions. Photograph by H. Cuzner upon large, dark, red-brown spots in great abundance, on the lower surface of the leaves. The summer-spores Stock Photo")
RMPG4EJA–. Minnesota plant diseases. Plant diseases. ;74 Minnesota Plant Diseases. occurs on other more or less closely related plants. The fungus mycelium gains entrance to the plant in the spring and first pro- duces cluster cups. These are followed by the summer spores, throughout the summer months, forming small red-brown patches. ]"lG. 199.—Leaf rust of roses. The cluster-cup stage on the stems and leaves. On left is a stem distorted by the cluster-cup cushions. Photograph by H. Cuzner upon large, dark, red-brown spots in great abundance, on the lower surface of the leaves. The summer-spores
RMRDCY08–. Manual of fruit diseases . Fruit. 66 MANUAL OF FRUIT DISEASES one on the upper surface. At maturity the walls of the cup- shaped structures split and recurve in a stellate manner. In cases of severe infection the leaves turn yellow and fall. Some- times 200 to 300 spots may occur on a single leaf. The diseased. Fig. is. — Cedar-apples in winter condition. fruits are recognized by the presence of the cup-shaped fruity ing bodies which are usually aggregated at the calyx-end. Not infrequently the lesions develop on the side or on the stem- end. As previously noted the fruits are dwarfed as a r
![. The fungi which cause plant disease . Plant diseases; Fungi. THE 'FUNGI WHICH CAUSE PLANT DISEASE 521 one in the center of each spot, but slightly prominent; conidia cylindric or clavate-cylindric, 10-25 x 1.5-2 n. On watermelon leaves. S. cucurbitacearum Sacc. is also on cucurbits. " S. cannabina Pk. is on hemp producing leaf spots. S, nicotianse Pat. is reported from France as the cause of tobacco leaf spotting."" S. doUchi B. & C. Spots white, with a broad, light brown margin; conidia straight, subfusiform, 3-septate, 40 m- On cowpeas."^ S. medicaginis Rob. & D Stock Photo](https://c8.alamy.com/comp/PG45PD/the-fungi-which-cause-plant-disease-plant-diseases-fungi-the-fungi-which-cause-plant-disease-521-one-in-the-center-of-each-spot-but-slightly-prominent-conidia-cylindric-or-clavate-cylindric-10-25-x-15-2-n-on-watermelon-leaves-s-cucurbitacearum-sacc-is-also-on-cucurbits-quot-s-cannabina-pk-is-on-hemp-producing-leaf-spots-s-nicotianse-pat-is-reported-from-france-as-the-cause-of-tobacco-leaf-spottingquotquot-s-douchi-b-amp-c-spots-white-with-a-broad-light-brown-margin-conidia-straight-subfusiform-3-septate-40-m-on-cowpeasquot-s-medicaginis-rob-amp-d-PG45PD.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. THE 'FUNGI WHICH CAUSE PLANT DISEASE 521 one in the center of each spot, but slightly prominent; conidia cylindric or clavate-cylindric, 10-25 x 1.5-2 n. On watermelon leaves. S. cucurbitacearum Sacc. is also on cucurbits. " S. cannabina Pk. is on hemp producing leaf spots. S, nicotianse Pat. is reported from France as the cause of tobacco leaf spotting."" S. doUchi B. & C. Spots white, with a broad, light brown margin; conidia straight, subfusiform, 3-septate, 40 m- On cowpeas."^ S. medicaginis Rob. & D Stock Photo")
RMPG45PD–. The fungi which cause plant disease . Plant diseases; Fungi. THE 'FUNGI WHICH CAUSE PLANT DISEASE 521 one in the center of each spot, but slightly prominent; conidia cylindric or clavate-cylindric, 10-25 x 1.5-2 n. On watermelon leaves. S. cucurbitacearum Sacc. is also on cucurbits. " S. cannabina Pk. is on hemp producing leaf spots. S, nicotianse Pat. is reported from France as the cause of tobacco leaf spotting."" S. doUchi B. & C. Spots white, with a broad, light brown margin; conidia straight, subfusiform, 3-septate, 40 m- On cowpeas."^ S. medicaginis Rob. & D
RMRE0BMD–. The wonder of life. Biology; Natural history; Zoology. Kallima, which is conspicuously coloured on the upper surface, but becomes like a withered leaf when it folds its wings together and exposes the brown under surface (Fig. 11). As we have noted, the nervures on the wings look Hke the veins on a leaf, and the sug- gestion of a mid- rib increases the resemblance. Spots on the wings look like holes on the leaf, and so on. In fact, perfection is attained by the combination of a number of items. Even the fact that the colora- tion of the under surface and the position of spots may vary a httle
RMPG4055–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. ^sr^C:. Fig. 30. Angular Leaf Spot of Cotton. (Photograph by Erwin F. Smith) spots turn purple and finally become dry and brown. The disease is apparently widely distributed in the southern states, but the organism has not yet been fully described.1 X. PEAR BLIGHT Bacillus amylovorus (Burrill) De Toni Arthur, J. C. Diseases of the Pear. N. Y. Agl. Exp. Sta. Rept. 3: 357-367. 1884. Arthur, J. C. History and Biology of Pear Blight. Proc. Phil. Acad. Nat. Sci. (1886): 322-341. pi. 3.
RMRDA7TN–. Injurious insects : how to recognize and control them . Insect pests; Insect pests. 276 PESTS OF ORCHARIi AXD SMALL FBVITS. Fig o94.—The Eight-spotted F':'rester. Slightlv enlarged. Orisrinal. ment. and ou each side of the body is a wa^y white longi- tudinal iiand. faint on the segments toward the head, but prominent toward the hind end. The adult moth is black, marked with eight large spots. The readiest means of control is to apply arsenate of lead or Paris green to the foUage. The Grape-leaf Skeletonizer (^ Harri.rina aDuricana Guer-!Men.) Orderly rows of small, yellowish, black-spotted c
![. The fungi which cause plant disease . Plant diseases; Fungi. 628 THE FUNGI WHICH CAUSE PLANT DISEASE C. apii Fr. Spots amphigenous, subcircular, pale-brown, 4-6 mm. in diame- ter, with a more or less definite elevated margin; conidiophores hy- pophylous, light-brown, fasciculate, con- tinuous or 1 or 2-septate, subundulate, 40-60 X 4-5 n; conidia hyaline obclavate, or almost cylindric, 3 to 10-septate, slen- der, 50-80 xi II. A serious leaf spot is produced on celery, parsnips, etc.'^""'^^ C. beticola Sacc."' ^sa Spots amphigenous, brownish, purple- bordered, becoming ashy cen Stock Photo](https://c8.alamy.com/comp/PG45G6/the-fungi-which-cause-plant-disease-plant-diseases-fungi-628-the-fungi-which-cause-plant-disease-c-apii-fr-spots-amphigenous-subcircular-pale-brown-4-6-mm-in-diame-ter-with-a-more-or-less-definite-elevated-margin-conidiophores-hy-pophylous-light-brown-fasciculate-con-tinuous-or-1-or-2-septate-subundulate-40-60-x-4-5-n-conidia-hyaline-obclavate-or-almost-cylindric-3-to-10-septate-slen-der-50-80-xi-ii-a-serious-leaf-spot-is-produced-on-celery-parsnips-etcquotquot-c-beticola-saccquot-sa-spots-amphigenous-brownish-purple-bordered-becoming-ashy-cen-PG45G6.jpg ". The fungi which cause plant disease . Plant diseases; Fungi. 628 THE FUNGI WHICH CAUSE PLANT DISEASE C. apii Fr. Spots amphigenous, subcircular, pale-brown, 4-6 mm. in diame- ter, with a more or less definite elevated margin; conidiophores hy- pophylous, light-brown, fasciculate, con- tinuous or 1 or 2-septate, subundulate, 40-60 X 4-5 n; conidia hyaline obclavate, or almost cylindric, 3 to 10-septate, slen- der, 50-80 xi II. A serious leaf spot is produced on celery, parsnips, etc.'^""'^^ C. beticola Sacc."' ^sa Spots amphigenous, brownish, purple- bordered, becoming ashy cen Stock Photo")
RMPG45G6–. The fungi which cause plant disease . Plant diseases; Fungi. 628 THE FUNGI WHICH CAUSE PLANT DISEASE C. apii Fr. Spots amphigenous, subcircular, pale-brown, 4-6 mm. in diame- ter, with a more or less definite elevated margin; conidiophores hy- pophylous, light-brown, fasciculate, con- tinuous or 1 or 2-septate, subundulate, 40-60 X 4-5 n; conidia hyaline obclavate, or almost cylindric, 3 to 10-septate, slen- der, 50-80 xi II. A serious leaf spot is produced on celery, parsnips, etc.'^""'^^ C. beticola Sacc."' ^sa Spots amphigenous, brownish, purple- bordered, becoming ashy cen
RMRDE38N–. Minnesota plant diseases. Plant diseases. 325 Minnesota Plant Diseases. >ft<f ife; «' The leaf blight of celery (Cercospora apii Fr.). The fungus, causing this disease is a loose spored, imperfect fungus. It causes the formation of red- dish to brownish spots on the leaves, which may spread and increase in size until the leaf is seriously injured. The fungus thrives well on plants in dry || situations and is particularly ! effective against young plants. When badly affected the leaf turns yellow and finally brown. Spots may also appear on the stem. The spores arise from upright fungus-
RMPG46EM–. The fungi which cause plant disease . Plant diseases; Fungi. 246 THE FUNGI WHICH CAUSE PLANT DISEASE. FiQ. 180.—M. sentina, Septona stage. Portion of a section through a pear leaf spot, showing e, e, epidermis; p, pali- sade cells sp, spongy parenchyma; o, S. piricola pycnidium, giving out spores, b. After Longyear. M. sentina (Fr.) Schr. Perithecia, 80-110 /i; on dead spots of leaves, the long ostiole erumpent; asci clavate, 60-75 x 11-13 fi, colorless; spores fusiform, curved or straight, 26-33 x Conidia (=Septoria piricola) borne in pycnidia which are similar in size and form to the perit
RMRDED3P–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fig. 214.—Cronai'tium asclepiadeum oji Ct/nanch^m Vincetoxicum. The uredo- sori sliow as spots, the teleutospore-sori as processes on the leaves, (v. Tubeuf del) also on Gentiana asclepiadea). The aecidial stage, known as Peridermium Oornui Eostr. et Kleb. produces a blister-rust on the bark of Pinus sylvestris.. Fig. 215.—Ci-onartium asclepiadeum. Section of a Cynanchum leaf. The leaf-parenchyma is permeated with m
RMPG45GE–. The fungi which cause plant disease . Plant diseases; Fungi. 622 THE FUNGI WHICH CAUSE PLANT DISEASE flask-shaped, strongly constricted at the septa, olive, 40-60 x 10-17 n. Circular leaf-spots are produced on violets. Spores are found on the spots only when conditions are most favorable, i. e., in a humid air. The parasitism of the fungus was demonstrated by inocula- tion with spores on living leaves in distilled water. A. panax Whet.^^e Spots amphigenous, circular, becoming dingy white with a. Fig. 420.—Alter- n a r i a. Spores and spore-bear- ing stalks. Af- ter van Hook.. Please note tha
RMRDCY1P–. Manual of fruit diseases . Fruit. 50 MANUAL OF FRUIT DISEASES the diseased portion is sunken. Older spots become lobed, due to the secondary extension of the pathogene from one or more points in the leaf. This activity results in a series of more or less concentric areas mak- ing up an irregular spot, but in which the outline of the original diseased portion can still be recognized (Fig. 12). The center of the lesion be- comes grayish brown and the entire affected area presents an appear- ance which has given rise to the name frog-eye (Fig. 12). Frequently the small black fruiting bodies of
Search Results for Leaf with spots Black & White Stock Photos and Images (407)
Page 3 of 5