RMMR4RR7–Engraving depicting potato blight (Phytophora Infestans). Leaves of the potato plant rot as an effect of potato blight, a fungal infection spread by aphids. It was not until the 1890s that the nature of the disease and its vector was properly understood. Dated 19th century
RFD0FNP2–Maple blight microscopic fungus plant disease vintage illustration from antique book 'The Playtime Naturalist', London UK, 1889.
RMRDFDYW–. Manual of tree diseases . Trees. MAPLE DISEASES 229 fungus. The spores from these structiu'es are disseminated by the rain. It is to be expected that perithecia with ascospores are formed in the leaves on the ground during the winter. The twigs have not been found affected. This disease is similar to the leaf- and twig-blight of sycamores described on page 333. The control measures are the same for both of these diseases. Canker Caused by Nectria cinnabarina Fries Maples are commonly affected by this canker. Other deciduous trees may also be attacked by this disease but it never assumes grea
RMPG14JA–. Manual of tree diseases . Trees. MAPLE DISEASES 229 fungus. The spores from these structiu'es are disseminated by the rain. It is to be expected that perithecia with ascospores are formed in the leaves on the ground during the winter. The twigs have not been found affected. This disease is similar to the leaf- and twig-blight of sycamores described on page 333. The control measures are the same for both of these diseases. Canker Caused by Nectria cinnabarina Fries Maples are commonly affected by this canker. Other deciduous trees may also be attacked by this disease but it never assumes grea
RMRDFE2W–. Chestnut blight. Chestnut blight; Chestnut. S46 Bulletin 347 iUustrations. The effects of the disease on the general appearance of the tree are most noticeable during the summer, when the trees are in leaf. In regions where the disease is common, the newly affected limbs and twigs are girdled in large numbers during the summer, and the brown, shriveled leaves are readily seen even at a distance. This most striking symptom is common during July and August, while the healthy parts of the tree are still green. The dead leaves also remain clinging to the limbs during the winter (Fig. 79). If the
RMPG4B3W–. Botany for agricultural students . Botany. POTATO BLIGHT (PHYTOPHTHORA INFESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonia and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues of the
RMRDWD5B–. Botany, with agricultural applications. Botany. POTATO BLIGHT (PHYTOPHTHORA INPESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonja and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues o
RMPG14R4–. Chestnut blight. Chestnut blight; Chestnut. S46 Bulletin 347 iUustrations. The effects of the disease on the general appearance of the tree are most noticeable during the summer, when the trees are in leaf. In regions where the disease is common, the newly affected limbs and twigs are girdled in large numbers during the summer, and the brown, shriveled leaves are readily seen even at a distance. This most striking symptom is common during July and August, while the healthy parts of the tree are still green. The dead leaves also remain clinging to the limbs during the winter (Fig. 79). If the
RMRDW9MA–. Textbook of botany. Botany. 3«o TEXTBOOK OF BOTANY. Fig. 214. — A potato leaf at- tacked by the late blight. This fungus can be fairly well controlled by spraying the grape plants with the well-known Bor- deaux mixture.^ 384. Late Blight and Rot of Potato. —This, commonly called the " potato disease," is at times very destructive and has been responsible for the " potato famines" of history. Because of its destructiveness it has been extensively studied and was one of the first plant diseases against ,which governments waged a real warfare. The fungus that causes the dise
RMPG3RH5–. Manual of fruit diseases . Fruit. APPLE DISEASES 135 Hypochnus Leaf-Blight Caused by Hypochnus ochroleuca Noack It is in the humid regions of the Appalachian Mountain valleys that Hypochnus leaf-blight is most destructive. The disease is known, however, fromMaine to Florida, and is most common in North Carolina, Florida, xlabama, Georgia and West A'irginia. The pathogene was probably introduced from Brazil, and is known to attack the apple, pear, quince, snowball and lilac. Si/mptom^ The chief damage is wrought through the loss of leaves. Affected trees are devitalized, and while twigs are
RMRDCXRC–. Manual of fruit diseases . Fruit. APPLE DISEASES 135 Hypochnus Leaf-Blight Caused by Hypochnus ochroleuca Noack It is in the humid regions of the Appalachian Mountain valleys that Hypochnus leaf-blight is most destructive. The disease is known, however, fromMaine to Florida, and is most common in North Carolina, Florida, xlabama, Georgia and West A'irginia. The pathogene was probably introduced from Brazil, and is known to attack the apple, pear, quince, snowball and lilac. Si/mptom^ The chief damage is wrought through the loss of leaves. Affected trees are devitalized, and while twigs are
RMPG4EN7–. Diseases of economic plants . Plant diseases. VEGETABLE AND FIELD CROPS 221 Powdery mildew (Erysiphe polygoni DC.)- — This mildew of the cucumber and cantaloupe in general appearance resembles that described for the grape. It is more com- mon under glass than in the open, and here indicates too much moisture and too little ven- tilation. It is sel- dom injurious in the field. Flowers of sul- phur applied to the hot water or steam pipes in the form of a paste is useful. Leaf blight, cer- cosporose {Cercos- pora Cucurbitoe Ell. &Ev.). —The spots of this disease are much hke those of altern
RMRDD7NF–. Botany for agricultural students . Botany. POTATO BLIGHT (PHYTOPHTHORA INFESTANS) 357 scattered about like spores. When the conidia germinate, instead of producing hyphae they produce zoospores, which, after swimming about for a few minutes, lose their cilia and begin to produce new hyphae. If favorably located, the new hyphae find entrance to a leaf through its stomata and start the disease anew. The oogonia and antheridia resemble those of Saprolegnia, but are produced on short hyphae within the tissues of the host. The oospore has a heavy wall and is not liberated until the tissues of the
RMPG4ENN–. Diseases of economic plants . Plant diseases. 218 DISEASES OF ECONOMIC PLANTS promising resistant variety has been reported by Blinn.* Spraying as recommended for cucurbs is effective. Downy mildew (Peronospora cubensis B. & C). — This disease is described under cucumber. It is widespread and constitutes one of the most serious cantaloupe diseases.. Fig. 99. — Cantaloupe showing complete death of vines attacked by leaf blight. After Blinn. Wilt, fusariose (Fusarium vasinfedum Atk. var. nivea E. F. Smith).— Under watermelon this wilt is sufficiently discussed. It is not nearly so frequent
RMRDW9M8–. Textbook of botany. Botany. Fig. 214. â A potato leaf at- tacked by the late blight. This fungus can be fairly well controlled by spraying the grape plants with the well-known Bor- deaux mixture.^ 384. Late Blight and Rot of Potato. âThis, commonly called the " potato disease," is at times very destructive and has been responsible for the " potato famines" of history. Because of its destructiveness it has been extensively studied and was one of the first plant diseases against ,which governments waged a real warfare. The fungus that causes the disease is very com- mon in
RMPG3YED–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 302 FUNGOUS DISEASES OF PLANTS encouraged by certain weakening influences, such as the age of the leaf, the presence of flea-beetle injuries, etc. When large spots near the margins of the leaves become confluent, such ex- tensive areas are affected that there may result a rolling up of the edge, which might be mistaken for the tip burn, a disease gener- ally due to climatic conditions. The injury from the early blight results, therefore, in an early death of the leaves, as a result
RMRDCY3M–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. CYLINDROSPORIUM. 489 As yet the disease has been observed in quantity only in the neighbourhood of Oberammergau (Upper Bavaria). C. padi Karst. Leaf-blight of cherry and plum. This dis- ease is most destructive in the nursery, causing premature defoliation of young trees; it may also cause severe injury to fruit-bearing trees. The leaves become spotted and perforated by holes caused by the falling out of withered sp
RMPG4ENC–. Diseases of economic plants . Plant diseases. VEGETABLE AND FIELD CBOPS 219 vine to droop throughout its lengibh. This is followed by death. The infection is spread by insects also through diseased soil. The disease has been reported from many states, — among them Nebraska, Wisconsin, Maryland, Massachusetts, Indiana, — and is presumably present in many others.. IPlG. 100.—The Pollock cantaloupe vines adjacent to those shown in Fig. 99, show- ing complete resistance to the leaf blight. After Blinn. Spraying with Bordeaux mixture, while beneficial in retarding the development of other disease
RMRDE373–. Diseases of economic plants . Plant diseases. VEGETABLE AND FIELD CROPS 221 Powdery mildew (Erysiphe polygoni DC.)- — This mildew of the cucumber and cantaloupe in general appearance resembles that described for the grape. It is more com- mon under glass than in the open, and here indicates too much moisture and too little ven- tilation. It is sel- dom injurious in the field. Flowers of sul- phur applied to the hot water or steam pipes in the form of a paste is useful. Leaf blight, cer- cosporose {Cercos- pora Cucurbitoe Ell. &Ev.). —The spots of this disease are much hke those of altern
RMPG4F5G–. Diseases of economic plants . Plant diseases. DISEASES OF SPECIAL CROPS 89 Hypochnose' (Hy- pochnus ochroleuca, Noack). •— Hypoch- nose is principally a leaf affection causing blight and loss of the leaves, and thereby weakening the vital- ity of the tree. Superficially this disease resembles the blight, with which it might be confounded by the casual ob- server. It may be readily distinguished, however, by two char- acters: first, the manner in which the leaves droop and mat together, which is quite different from the habit of the blight, the leaves of which neither droop nor mat; second, b
RMRDJF1C–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 302 FUNGOUS DISEASES OF PLANTS encouraged by certain weakening influences, such as the age of the leaf, the presence of flea-beetle injuries, etc. When large spots near the margins of the leaves become confluent, such ex- tensive areas are affected that there may result a rolling up of the edge, which might be mistaken for the tip burn, a disease gener- ally due to climatic conditions. The injury from the early blight results, therefore, in an early death of the leaves, as a result
RMPG3N85–. Manual of fruit diseases . Fruit. 348 MANUAL OF FRUIT DISEASES l)een the subject of horticultural writings and discussions for many years. Very recently it was found on pears in Australia. As already indicated, the disease is found more commonly in nurseries than in orchards, yet the latter are not exempt from attacks of the leaf-blight pathogene. In the nursery the trouble affects the leaves and twigs of seedlings; in the orchard, the fruits (Fig. 98), in addition, are susceptible. It appears that all varieties show the disease, yet the KiefFer and Angouleme are more resistant than the Seck
RMRDEX4C–. Diseases of economic plants . Plant diseases. DISEASES OF SPECIAL CROPS 89 Hypochnose' (Hy- pochnus ochroleuca, Noack). •— Hypoch- nose is principally a leaf affection causing blight and loss of the leaves, and thereby weakening the vital- ity of the tree. Superficially this disease resembles the blight, with which it might be confounded by the casual ob- server. It may be readily distinguished, however, by two char- acters: first, the manner in which the leaves droop and mat together, which is quite different from the habit of the blight, the leaves of which neither droop nor mat; second, b
RMPG3TGE–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. CYLINDROSPORIUM. 489 As yet the disease has been observed in quantity only in the neighbourhood of Oberammergau (Upper Bavaria). C. padi Karst. Leaf-blight of cherry and plum. This dis- ease is most destructive in the nursery, causing premature defoliation of young trees; it may also cause severe injury to fruit-bearing trees. The leaves become spotted and perforated by holes caused by the falling out of withered sp
RMRE2JY8–. Introduction to botany. Botany. 240 INTRODUCTION TO BOTANY by the grape leaf, until the fungus permeates the entire leaf. If the leaf is not able to make a surplus of food material, the amount taken by the parasite may result in the starvation and death of the grape leaf. Possibly, also, the parasite may excrete substances that poison the host plant.. Fio. 187. Experiments in destroying potato blight Photograph by the New York Agricultural Experiment Station illustrating the results of spraying potatoes to prevent disease. Those that were not sprayed yielded at the rate of 161 bushels per ac
RMPG4EPX–. Diseases of economic plants . Plant diseases. 202 DISEASES OF ECOKOMIC PLANTS It is reported upon many species of true beans (Phaseolus) and upon related genera a Msgna, Falcata, Strophostyles. If the disease proves destructive, clean culture, the de- struction of all wintering forms, is advisable. Blight (Pseudomonas phaseoli E. F. Smith).—Beans of various kinds are subject to a blight which manifests. Fig. 90. — Bacteriosis of bean leaves. After Fulton. itself upon the pod, leaf, or stem. It has been reported from various states, from Canada, is viddely distributed, and often quite destruc
RMRE1GY6–. Fungi and fungicides. Fungi; Fungicides. Fig. 7. Rose leaf black spot.. Fig. 8. strawberry leaf blight. division between the healthy and diseased tissue. As the season advances these spots increase in size, and, merging with others, form irregular, longitudinal blotches, which in very bad cases girdle the cane. Use the Bordeaux mixture (diluted formula) before the leaves open, and repeat at intervals of two weeks, spraying the canes which are starting out of the ground. Removing the old canes and burning them will greatly reduce the disease.. Please note that these images are extracted from
RMPG14K5–. 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
RMRDCX6C–. Manual of fruit diseases . Fruit. 348 MANUAL OF FRUIT DISEASES l)een the subject of horticultural writings and discussions for many years. Very recently it was found on pears in Australia. As already indicated, the disease is found more commonly in nurseries than in orchards, yet the latter are not exempt from attacks of the leaf-blight pathogene. In the nursery the trouble affects the leaves and twigs of seedlings; in the orchard, the fruits (Fig. 98), in addition, are susceptible. It appears that all varieties show the disease, yet the KiefFer and Angouleme are more resistant than the Seck
RMPG4EP7–. 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-
RMRDWPNH–. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. PHYTOPHTHORA 233 the ground, they can, in the presence of moisture, produce zoo- spores, as in Cysiopns. The first signs of disease are discoloured spots exhibiting a dark central region surrounded by successive zones of greyish and pale green tissue, which rapidly become brown or even blackish ; closer inspection discloses the white. Fig. 124.—Asexual reproduction in various Oomycetes. A, Small part of epidermis of Potato-leaf, infected with Blight (Phytophthora infes- ians), showing branched hypha; bearing
RMPG3MGB–. Manual of fruit diseases . Fruit. 388 MANUAL OF FRUIT DISEASES. Fio. 112. — Fire-blight on quince. varieties are sus- ceptible. The fire- blight disease is dis- cussed in detail under Pear (page 323). A special consideration of nursery quinces should supplement the treatment as outlined for fire- blight of the pear. To avoid blossom- blight it is regarded as good practice to remove all blossom- buds from the two- year-old quince trees; this should be done before the flowers open to avoid initial infec- tion. Leaf-Blight Caused by Fabroea maculata (Lev.) Atk. This disease occurs also on the p
RMRDE37D–. Diseases of economic plants . Plant diseases. VEGETABLE AND FIELD CBOPS 219 vine to droop throughout its lengibh. This is followed by death. The infection is spread by insects also through diseased soil. The disease has been reported from many states, — among them Nebraska, Wisconsin, Maryland, Massachusetts, Indiana, — and is presumably present in many others.. IPlG. 100.—The Pollock cantaloupe vines adjacent to those shown in Fig. 99, show- ing complete resistance to the leaf blight. After Blinn. Spraying with Bordeaux mixture, while beneficial in retarding the development of other disease
RMPG4EN3–. Diseases of economic plants . Plant diseases. 220 DISEASES OF ECONOMIC PLANTS many states. From 50 to 100 per cent damage was reported from Nel)raska in 1905. The disease is discussed under watermelon. Southern blight (Sclerotium Roljsii Sacc. in litt.).— A large percentage of the cantaloupe crop in the southern-. FiG. 101.—Leaf spotted with downy mildew. Original. most states is often destroyed by this disease. It is par- ticularly noticeable on fruit upon the side touching the ground, first as a slight rot, followed by a white fringe of fungous threads which soon surround the whole fruit.
RMRDE37W–. Diseases of economic plants . Plant diseases. 218 DISEASES OF ECONOMIC PLANTS promising resistant variety has been reported by Blinn.* Spraying as recommended for cucurbs is effective. Downy mildew (Peronospora cubensis B. & C). — This disease is described under cucumber. It is widespread and constitutes one of the most serious cantaloupe diseases.. Fig. 99. — Cantaloupe showing complete death of vines attacked by leaf blight. After Blinn. Wilt, fusariose (Fusarium vasinfedum Atk. var. nivea E. F. Smith).— Under watermelon this wilt is sufficiently discussed. It is not nearly so frequent
RMPG4B1B–. Botany for agricultural students . Botany. Fig. 322. —Pus- tules on the bark of n Chestnut caused by the Chestnut Blight Fungus. From Bulletin 380, U. S. Dept. Agri- culture, 1917. Fig. 323. — Powdery Mildew on an Apple leaf. The light areas arc due to the presence of many superficial hyphae. From BuUelin ISO, Maine Agr. Exp. Sta. produced {Fig. 322). The summer spores are extruded in threads and spread the disease to other trees. In autumn these same pustules develop deeply buried perithecia in which the ascospores (winter spores) develop. The ascospores germinate the next spring and when c
RMRE1GYD–. Fungi and fungicides. Fungi; Fungicides. A. Fig. 5. Pear cracking. Fig. 6. Leaf blight. of fruits which do not indicate much outward attack will show a brownish, rotten appearance when cut open. •Wherever the disease exists, care should be taken to gather all diseased fruit, generally known as mummied fruit, which may cling to the fruit spurs or fall to the ground, as the spores thereon will infect the next year's crop. The same remedies as are used for pear scab will check this disease.. Please note that these images are extracted from scanned page images that may have been digitally enhanc
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
RMRDE39P–. Diseases of economic plants . Plant diseases. 202 DISEASES OF ECOKOMIC PLANTS It is reported upon many species of true beans (Phaseolus) and upon related genera a Msgna, Falcata, Strophostyles. If the disease proves destructive, clean culture, the de- struction of all wintering forms, is advisable. Blight (Pseudomonas phaseoli E. F. Smith).—Beans of various kinds are subject to a blight which manifests. Fig. 90. — Bacteriosis of bean leaves. After Fulton. itself upon the pod, leaf, or stem. It has been reported from various states, from Canada, is viddely distributed, and often quite destruc
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
RMRDW9JC–. Textbook of botany. Botany. 388 TEXTBOOK OF BOTANY crops in order to eliminate the disease. It has been found that lime, ashes, and horse manure tend to increase the growth of the fungus. Care must be taken to use only dis- infected potatoes for planting. 392. Peach Scab. — This is a common and well-known disease, found on almost all second- and third-grade peaches. Fig. 2 2 2. — A potato leaf at- tacked by the early blight. Fig. 223. — A bean plant inoculated with the imperfect fungus which causes anthracnose—a disease which is at times very serious, attacking the younger parts of the stem,
RMPG44R7–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. Fig. 105.—Septoria leaf spot disease of celery, or celery blight. (After Coons, G. N., and Levin, Ezra, Spec. Bull. 77, Mich. Agric. Coll. Exper. Stat., March. 1916. 5P0BES . Fig. 106.—Section through leaf spot of celery blight {Septoria) showing hyphae) in leaf tissue and pycnidium with exuding pycnospores. (After Coons, G. H., and Levin, Ezra, Spec. Bull. 77. Mich. Agric. Coll. Exper. Stat., March, 1916.). Please note that these images are extracted from scanned page images that may h
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
RMPG3NWW–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 358 FUNGOUS DISEASES OF PLANTS XLIX. LEAF SPOT OF THE PEAR Septoria Pyricola Desm. Duggar, B. M. Some Important Pear Diseases. Leaf Spot. Cornell Agl. Exp. Sta. Built. 145: 597-611. figs. 157-163. 1898. The leaf spot of pear is a disease which may be readily dis- tinguished from the leaf blight subsequently described. It occurs throughout the eastern United States as an important fungus, both. Fig. 176. Leaf Spot of Pear in orchards and nurseries. It is probably found throughout No
RMRDCX43–. Manual of fruit diseases . Fruit. 388 MANUAL OF FRUIT DISEASES. Fio. 112. — Fire-blight on quince. varieties are sus- ceptible. The fire- blight disease is dis- cussed in detail under Pear (page 323). A special consideration of nursery quinces should supplement the treatment as outlined for fire- blight of the pear. To avoid blossom- blight it is regarded as good practice to remove all blossom- buds from the two- year-old quince trees; this should be done before the flowers open to avoid initial infec- tion. Leaf-Blight Caused by Fabroea maculata (Lev.) Atk. This disease occurs also on the p
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
RMRDWD30–. Botany, with agricultural applications. Botany. Fig. 322.— Pus- tules on the bark of a Chestnut caused by the Chestnut Blight Fungus. From Bulletin 380, U. S. Dept. Agri- culture, 1917.. Fig. 323.— Powdery Mildew on an Apple leaf. The light areas are due to the presence of many sujjerficial hyphae. From Bulletin 185, Maine Agr. Exp. Sta. produced {Fig. 322). The summer spores are extruded in threads and spread the disease to other trees. In autumn these same pustules develop deeply buried perithecia in which the ascospores (winter spores) develop. The ascospores germinate the next spring and
RMPG1KAE–. Southern field crops (exclusive of forage plants). Agriculture. COTTON BISMASES 419 389. Sore-shin, or damping off (Rhizoctonia). ^ The fungus causing this disease penetrates the stems of the. Fig. 184. — Diseased Leaves, Boll, and Stems op Cotton Plant. Showing several forms of bacterial blight, known on the leaves as angu- lar leaf-spot; on the stems as black arm; and on the bolls as bacterial boll-rot. very young cotton plants just below the surface of the soil. Some of the diseased plants die, while others recover. It is worse in wet weather. Any method of hastening the drying of the sur
RMRDE37B–. Diseases of economic plants . Plant diseases. 220 DISEASES OF ECONOMIC PLANTS many states. From 50 to 100 per cent damage was reported from Nel)raska in 1905. The disease is discussed under watermelon. Southern blight (Sclerotium Roljsii Sacc. in litt.).— A large percentage of the cantaloupe crop in the southern-. FiG. 101.—Leaf spotted with downy mildew. Original. most states is often destroyed by this disease. It is par- ticularly noticeable on fruit upon the side touching the ground, first as a slight rot, followed by a white fringe of fungous threads which soon surround the whole fruit.
RMPG4F1X–. Diseases of economic plants . Plant diseases. 116 DISEASES OF ECONOMIC PLANTS APRICOT Yellows. See peach. Phyllostictose. See peach. Brown rot. See peach. Blight {Bacillus amylovorus (Burr.) De Toni).—The. Fig. .50. — Unsprayed cherry tree defoliated by leaf spot. After Scott. usual blight of the apple and pear has been reported upon the apricot by Paddo«k. CHERRY Leaf spot (Cylindrosporium Padi Karst).— For de- scription, see plum. The disease is very widespread throughout the United States, and it is often very de- structive. The loss in Ohio in one year was estimated at. Please note that
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-
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
RMRDCYCC–. Botany for agricultural students . Botany. Fig. 322. —Pus- tules on the bark of n Chestnut caused by the Chestnut Blight Fungus. From Bulletin 380, U. S. Dept. Agri- culture, 1917. Fig. 323. — Powdery Mildew on an Apple leaf. The light areas arc due to the presence of many superficial hyphae. From BuUelin ISO, Maine Agr. Exp. Sta. produced {Fig. 322). The summer spores are extruded in threads and spread the disease to other trees. In autumn these same pustules develop deeply buried perithecia in which the ascospores (winter spores) develop. The ascospores germinate the next spring and when c
RMPG44RA–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. FUNGI IMPERFECTI (dEUTEROMYCETEs) 263. Fig. 105.—Septoria leaf spot disease of celery, or celery blight. (After Coons, G. N., and Levin, Ezra, Spec. Bull. 77, Mich. Agric. Coll. Exper. Stat., March. 1916. 5P0BES . 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.. Harshberger, John W. (John William), 1869-1929. Philadel
RMRDJ632–. 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
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.
RMRDJ62N–. 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
RMPG4FBE–. Diseases of economic plants . Plant diseases. 14 DISEASES OF ECONOMIC PLANTS The California vine disease in 1892, $10,000,000. Pierce. Wheat rust in the United States, 18981 $67,000,000. Galloway. Wheat rust in Illinois, 1885, $1,875,000. Burrill. Violet, leaf spot in the United States, 1900, $200,000. Dorsett. Peach leaf curl in the United States, 1900, $2,335,000. Pierce. Potato late blight in New York, 1904, $10,000,000. Stewart. Oat smut in the United States, annual, $6,500,000. Orton. Wheat loose smut, United States, annual, $3,000,000. Orton. Wheat bunt in the United States, annual, $1
RMRE40HD–. Vegetable forcing. Forcing (Plants); Vegetable gardening. 296 VEGETABLE FORCING of greenhouse tomatoes. Bordeaux mixture is appar- ently the best spray material to combat this disease. Various other diseases, such as Fusarium wilt, anthrac- nose, mosaic or calico leaf and bacterial blight, are often found on greenhouse tomatoes, but the most important diseases are the Leaf Mold and Blossom-End Rot.. Fig. 95.— Each paper box holds six pounds of tomatoes, and eight boxes may be packed in a standard bushel box, such as is usci in the Boston district. Marketing.—Greenhouse tomatoes should not be
RMRDE23N–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. Fig. 105.—Septoria leaf spot disease of celery, or celery blight. (After Coons, G. N., and Levin, Ezra, Spec. Bull. 77, Mich. Agric. Coll. Exper. Stat., March. 1916. 5P0BES . Fig. 106.—Section through leaf spot of celery blight {Septoria) showing hyphae) in leaf tissue and pycnidium with exuding pycnospores. (After Coons, G. H., and Levin, Ezra, Spec. Bull. 77. Mich. Agric. Coll. Exper. Stat., March, 1916.). Please note that these images are extracted from scanned page images that may h
RMRDJ65K–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 358 FUNGOUS DISEASES OF PLANTS XLIX. LEAF SPOT OF THE PEAR Septoria Pyricola Desm. Duggar, B. M. Some Important Pear Diseases. Leaf Spot. Cornell Agl. Exp. Sta. Built. 145: 597-611. figs. 157-163. 1898. The leaf spot of pear is a disease which may be readily dis- tinguished from the leaf blight subsequently described. It occurs throughout the eastern United States as an important fungus, both. Fig. 176. Leaf Spot of Pear in orchards and nurseries. It is probably found throughout No
RMRDE36A–. 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
RMRDEWWY–. Diseases of economic plants . Plant diseases. 116 DISEASES OF ECONOMIC PLANTS APRICOT Yellows. See peach. Phyllostictose. See peach. Brown rot. See peach. Blight {Bacillus amylovorus (Burr.) De Toni).—The. Fig. .50. — Unsprayed cherry tree defoliated by leaf spot. After Scott. usual blight of the apple and pear has been reported upon the apricot by Paddo«k. CHERRY Leaf spot (Cylindrosporium Padi Karst).— For de- scription, see plum. The disease is very widespread throughout the United States, and it is often very de- structive. The loss in Ohio in one year was estimated at. Please note that
RMRDA7PP–. Southern field crops (exclusive of forage plants). Agriculture. COTTON BISMASES 419 389. Sore-shin, or damping off (Rhizoctonia). ^ The fungus causing this disease penetrates the stems of the. Fig. 184. — Diseased Leaves, Boll, and Stems op Cotton Plant. Showing several forms of bacterial blight, known on the leaves as angu- lar leaf-spot; on the stems as black arm; and on the bolls as bacterial boll-rot. very young cotton plants just below the surface of the soil. Some of the diseased plants die, while others recover. It is worse in wet weather. Any method of hastening the drying of the sur
RMREM18E–. Circular (Pennsylvania Department of Agriculture. Bureau of Zoology.), 1918. Agricultural pests; Agriculture. 17 Early Blight is distinctly a leaf spot disease which produces cir- cular or ovate brown spots with concentric lines, and can be readily distinguished from tip burn. Control:—Bordeaux mixture applied when plants are young. Fig. 16. Late Blight and Rot attack foliage causing indefi- nite brown or black areas, and if uncontrolled run down, causing large blackened irregular spots in the flesh of the tubers.. Please note that these images are extracted from scanned page images that may
RMREN452–. Insects affecting vegetables [microform]. Légumes; Vegetables; Insect pests; Insectes nuisibles. Fig. 66. Late Blight. Fig. 66. Early Blight Early Blight or Leaf Spot Disease {Alternaria solani). This dis- ease sometimes appears when the plants are from 6 to 8 inches high, but is most abundant about the time the tubers are forming. In severe cases the foliage is badly damaged and the tubers remain small. Un- healthy plants and those attacked by the flea-beetle suffer most from this disease. Small scattered grayish brown circular spots are first observed upon the leaves. These take on a minut
RMRDCXP2–. 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
RMRDE240–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. FUNGI IMPERFECTI (dEUTEROMYCETEs) 263. Fig. 105.—Septoria leaf spot disease of celery, or celery blight. (After Coons, G. N., and Levin, Ezra, Spec. Bull. 77, Mich. Agric. Coll. Exper. Stat., March. 1916. 5P0BES . 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.. Harshberger, John W. (John William), 1869-1929. Philadel
RMRDJG14–. 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.
RMRDEXE7–. Diseases of economic plants . Plant diseases. 14 DISEASES OF ECONOMIC PLANTS The California vine disease in 1892, $10,000,000. Pierce. Wheat rust in the United States, 18981 $67,000,000. Galloway. Wheat rust in Illinois, 1885, $1,875,000. Burrill. Violet, leaf spot in the United States, 1900, $200,000. Dorsett. Peach leaf curl in the United States, 1900, $2,335,000. Pierce. Potato late blight in New York, 1904, $10,000,000. Stewart. Oat smut in the United States, annual, $6,500,000. Orton. Wheat loose smut, United States, annual, $3,000,000. Orton. Wheat bunt in the United States, annual, $1
Download Confirmation
Please complete the form below. The information provided will be included in your download confirmation