RF2JE2XWD–Black and white image of three bunches of Milkweed flowers, Asclepias, with leaves, spring or summer, Lancaster County, Pennsylvania
RMJYA877–Colleagues at Alumni Banquet, including Arthur Sarnoff (near side, left), at the time a recent graduate and permanent class president of the Johns Hopkins University; American television host Lynn Poole (back, far left); plant biochemist Al Nason (far back, center); Paul Kane (front center of far table), director of the Johns Hopkins Science Review; biochemist William D McElroy (in bow tie at center back of far table); Robert Fenwick (far back, second from left), associate producer for WAAM Baltimore; Glenn Lehman (front table, center), chief engineer for WAAM Baltimore; Ben Wolfe (front table
RFT5NNRG–Mistletoe is a hemi-parasitic plant in the order Santalales, attached to Host Plant. It is distributed throughout Eurasia from Great Britain to northe
RF2DHX3DB–Black and white photo of a perennial host plant.
RMKY8XDN–Engraving of a species of parasitic tree growing on a coconut palm in the tropics. From an original engraving in the Harper's Story Books by Jacob Abbott, 1854.
RFT61G34–A picture shows Dodder on Golden Rod. It show; A. enlarged section of a portion of willow stem, B. A vine, s. seedling dodder plant, h. stem of host,
RM2H9M9YF–£uczyce, 1948-09-06. Zakoñczenie elektryfikacji wsi i do¿ynki w dniu œwiêta reformy rolnej. Nz. dyrektor Zjednoczenia Elektrycznego Okrêgu Krakowskiego in¿. Drobot otrzymuje wieniec z r¹k gospodarza do¿ynek. wb PAP Luczyce, Sept. 6, 1948. The conclusuion of countryside electrification and harvest festival on the day of agricultural reform. Pictured: Cracow District Electric Plant director engineer Drobot receives a wreath of harvested crop from the festival host. wb PAP
RF2GTM6AK–Stem of common milkweed (Aslepias syriaca) in fall, showing maturing seed pods and last leaves of the season. Essential host of monarch butterfly.
RF2E07DD0–Old botanical illustration engraving of Autumn Hawkbit / Scorzoneroides autumnalis, Leontodon autumnalis. Traditional herbal plant. See Notes
RM2CENHRK–. Agriculture for southern schools. there again. As soon as a host plant throws out roots, theclover germs attach themselves to the root, multiply rapidly, and form a tubercle. Strange tosay, clover germs will not growon cowpea roots. Perhaps thisis because the clover germ has Red Clover I, inoculated; 2, notinoculated. become accustomed to liv-ing on the special kind offood it finds in clover sap,and perhaps the diet thecowpea or alfalfa offersdoes not agree with it. If afertilizer factory is started,it must be by germs accus-tomed to work on that kindof plant or on one veryclosely akin to it
RM2WG0K3D–Volunteer fete given by Mr. Harvey, the High Sheriff of Norfolk, at Crown Point, near Norwich: the Sports, 1862. '...the sports...comprised a hurdle-race for mounted volunteers, foot and wheelbarrow races, a post-office, a wheel of fortune, the songs of a band of Christy's minstrels; the comicalities of that most primitive of our dramatic representations, Punch and Judy; conjuring, vaulting, the climbing of greasy poles, and a host of other amusements...The festivities closed, soon after nightfall, with a magnificent display of fireworks, by Mr. Tucker, of the Cremorne Gardens. Thus ended a fe
RF2HG4499–black cat is sitting next to a bowl of food and waiting for food. Looking up at the host.
RM2F3EKTB–Black on white, side view of a monarch butterfly / danaus plexippus on a milkweed flower. The flower looks like a fairy.
RM2FNGC0P–Germany, Espenhain, 07.01.1990. Archive-No.: 12-09-20 The Kombinat Espenhain (more precisely VEB Kombinat Espenhain) was a plant for the extraction and processing of brown coal. Photo: View of the plant [automated translation]
RF2HX984G–This ivy has a firm grip on its host, an oak tree
RMPG2M50–. Parasitic fungi of Illinois / by T.J. Burrill. Fungi. Parasitic Fungi of Illinois. 395 roses, hops, gooseberries, raspberries, grapes,* and of many ornamental plants and trees, is caused by different species of this family. As their development is superficial, they are easily reached by remedial agents. Sulphur has long been successfully used to check the ravages of the grape mildew, and as a^ remedy for rose mildew in greenhouses. Its use is often indiscriminately recommended for any and all of these diseases, but the caution should be added, that, in some cases, the host plant suffers more
RMPYY8FB–Indian Bollywood Hindi Film actor Amitabh Bachchan, India, Asia, 1900s
RMA9Y15P–Black and white image of Ivy creeping and climbing up a tree
RF2HJ6RWM–Local Dining in Guest House in Japan
RMA1R262–Forbidden City Imperial Palace UNESCO World Heritage Site Beijing Peking China Chinese Asian Asiatic Asia
RM2ABX69M–JOHN P. LOVELL ARMS CO. 147 Washington Street BOSTON MASS. FORGING AND WELDING BY PETROLEUM AIR BLAST FIRES. ONE STAII SATE SAW WILL DO Al ESTE .dat JENKINS STANDARD PACKING! MILK ST. BOSTON MASS. MACHINE-MOLDE Driving Plant for Cable Railways. LEFFEL TURBINE WATER WHEELS. Shaftirg Pulleys and Hangers. NEW KODAKS SY MAIDEN LANE ESTABLISHED 1546. The Host Popular Scientific Paper in the World. 52 Numbers a Year. able t MVNN 464 CO. 361 Broadway New York. 'I' IIM MUNN 417. Co. 361 Broadway N. Y Building Edition. MUNN a CO. Publishers 361 Broadway New York. PRINTING INKS. Victor Bicycles VICTORS
RFMXCWKH–looming summer flowers seen in a garden. Insects and larva are seen eating the petals and nectar.
RM2CENHXW–. Agriculture for southern schools. Fig. 110. — SoEGHuji from Equal Areas In center, fertilized with rye; on left, with vetch, entire growth; on right, with vetch stubble. soil by means of water. These little workmen are alive.They must wait until the same kind of legume is planted 170 AGKICULTLTRE. there again. As soon as a host plant throws out roots, theclover germs attach themselves to the root, multiply rapidly, and form a tubercle. Strange tosay, clover germs will not growon cowpea roots. Perhaps thisis because the clover germ has Red Clover I, inoculated; 2, notinoculated. become accust
RM2FNGBXK–Germany, Espenhain, 07-01-1990. Archive-No: 12-09-28 The Kombinat Espenhain (more precisely VEB Kombinat Espenhain) was a plant for the extraction and processing of brown coal. Photo: View of the plant [automated translation]
RMPG3FKD–. A textbook of botany for colleges and universities ... Botany. SAPROPHYTISM AND SYMBIOSIS 769 terial diseases. In some cases " disease-resistance " involves very complicated phenomena; for example, when the olive is infected by Bacterium Oleae, there are developed in the host plant, layers of scleren- chyma and cork that isolate the bacteria, and antibodies are formed which are specifically toxic to the bacteria. In the lack of all obvious determining factors, appeal sometimes has been made to inherent hidden differences between the various members of a given species, but this &quo
RMRE0RTN–. An introduction to vegetable physiology. Plant physiology. 206 VEGETABLE PHYSIOLOGY dependence of one form, the parasite, upon the other, the host. As in the case of the insectivorous plants, there are members of this class which are provided with a chlorophyll apparatus, and which are therefore indebted to their hosts for protein substances only, or perhaps also for certain of their ash constituents. As these almost without exception fasten themselves upon the roots of the host plant, they are frequently spoken of as root-'parasites. Prom their general. Fxu. 99.—Thesium alpinum, showinq the
RM2FNGC0K–Germany, Espenhain, 07.01.1990. Archive-No.: 12-09-33 The Kombinat Espenhain (more precisely VEB Kombinat Espenhain) was a plant for the extraction and processing of brown coal. Photo: View of the plant [automated translation]
RMPG3P19–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 3i8 FUNGOUS DISEASES OF PLANTS spreads to the stem and leaves. Entrance to the tubers is gained, therefore, as a rule, through the stems upon which they are borne. The vascular system of the host plant is discolored, al- though frequently the tubers are not seriously injured externally until after they are gathered. In storage, however, the fungus progresses rapidly, blackening the vascular ring. At this stage the disease is only made apparent in the tubers by cutting them crosswis
RMRDYHKY–. An introduction to vegetable physiology. Plant physiology. 200 VEGETABLE PHYSIOLOGY themselves upon the roots of the host plant, they are frequently spoken of as root-parasites. From their general structure and their relationship to the host plant, they evidently have much in common with the Mistletoe, and it is not very easy to distinguish between their semi- parasitism and the symbiosis of the latter with the trees on which it lives. They are, however, usually herbaceous jy/. Fig. 99.—Thesium alpinum, showing the Suckebs on the Roots. (After Kerner.) forms, and can therefore be of no use
RM2FNGC05–Germany, Espenhain, 07.01.1990. Archive-No.: 12-09-12 The Kombinat Espenhain (more precisely VEB Kombinat Espenhain) was a plant for the extraction and processing of brown coal. Photo: View of the plant [automated translation]
RMPG43M5–. The diseases of crops and their remedies : a handbook of economic biology for farmers and students. Plant diseases. MISCELLAirmVS CROPS. 147 group of which the " smnts " are important members. Fig. 49 represents a transverse section of a root with nodule. In very thin sections under high.power, the nodules are seen to be filled with hyphse and spores. The spores of this fungus are more or less v-shaped, and are formed by division of the protoplasmic contents of the hyphal filaments which ramify in the root-tissues of the host-plant. Unlike most of the members of the Ustila- ginece,
RMRDWB12–. Plants; a text-book of botany. Botany. Fig. 39. A branch of Peronoffpora in contact with two cells of a host plant, and sending into them its large haustoria.—After DeBakv. i-':^^;- L'lfig.--. 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.. Coulter, John Merle, 1851-1928. New York, D. Appleton and company
RM2FNGC1C–Germany, Espenhain, 07.01.1990. Archive-No.: 12-09-31 The Kombinat Espenhain (more precisely VEB Kombinat Espenhain) was a plant for the extraction and processing of brown coal. Photo: View of the plant [automated translation]
RMPG1HHC–. A manual of weeds : with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control . Weeds. OONVOLVULACEAE (.CONVOLVULUS FAMILY) 325 dies; if there is such a plant, the parasite quickly twines about it, develops tiny, wart-like suckers at the point of contact, breaks connection with the earth, and thereafter "sponges its living," drawing from the host plant the food assimilated by the green leaves for its own growth. Con- sequently the Dodder needs no leaves and has none, the whol
RMRDHK2W–. A textbook of botany for colleges and universities ... Botany. SAPROPHYTISM AND SYMBIOSIS 769 terial diseases. In some cases " disease-resistance " involves very complicated phenomena; for example, when the olive is infected by Bacterium Oleae, there are developed in the host plant, layers of scleren- chyma and cork that isolate the bacteria, and antibodies are formed which are specifically toxic to the bacteria. In the lack of all obvious determining factors, appeal sometimes has been made to inherent hidden differences between the various members of a given species, but this &quo
RMPG40JD–. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 144 SYSTEMATIC BOTANY. Pig. 260), or many-celled (as in Phragmidium). They rupture the epidermis and become exposed, but generally remain attached to their host-plant during the winter. In the spring, they germinate by sending out from each cell a jointed filament, called the promycelium. In small branches of the promycelium, small terminal cells, or sporidia, are formed. These are carried about by the wind, an
RMRDXHC1–. Introduction to the study of fungi; their organography, classification, and distribution, for the use of collectors. Fungi. 8o INTRODUCTION TO THE STUDY OF FUNGI of the stosa&ta of the host-plant, where it becomes the new mycelium of a spore:bed, which may either be that "of a uredo- spore or a" teleTffippare! The violet leaves which display on their under surface the pale-brown^cattered^pustules of the uredospores, will, later in thlTseason, exhibit aksojrimUar pustuEsjEnxeJ'with them^and nearly of the same size and form, but much darker in colour, or -the leaf may be occupied
RMPG4F83–. Minnesota plant diseases. Plant diseases. 212 Minnesota Plant Diseases. without injury to the host plant. Only the best-known and well-established formulae will be considered here. For de- tailed accounts of the action on specific diseases, the special portion of this work should be consulted, as also the experi- ment station bulletins of the Department of Agriculture. A great many of the bulletins of the Department of Agriculture and of the various Experiment Stations have been consulted in compiling these formulae. These may be referred to for fur- ther detail. The value of spraying in agr
RMRDW9NK–. Botany for high schools and colleges. Botany. nSTJLAQINEuS. 321 there grow out small sporidia, which germinate by sending out a slender hypha; when this hypha comes in contact with the proper host plant, it penetrates the walls of its. 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.. Bessey, Charles E. (Charles Edwin), 1845-1915. New York : H. Holt
RMPG1REJ–. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. THALLOPHYTA. 669 Peronosporece.—Are mostly parasitic upon Flowering Plants, and the cause of many destructive diseases. They estabhsh themselves by means of a branching, tubular, non-septate mycelium which penetrates the intercellular system of the host- plant (c/. p. 56). They propagate asexually by means of unicellular sporangia borne on branched hyphse which project from the stomates, &c., of the host (c/. fig. 38V); these sporangia (or spores as they are sometimes termed) liberate on a moist
RMRDWA89–. Botany for high schools and colleges. Botany. BSTILAGINK^. 321 there grow out small sporidia, which germinate by sending out a slender hypha; when this hypha comes in contact with the proper host plant, it penetrates the walls of its. 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.. Bessey, Charles E. (Charles Edwin), 1845-1915. New York : H. Holt
RMPG0PRY–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. IOO FUNGOUS DISEASES OF PLANTS Morphology. Fungus and deformity. The parasite is sup- posed to gain entrance to the host plant during the swarmspore stage, or immediately upon leaving the swarmspore stage, there- fore in the amceboidal form. No observations, however, have been made relative to host penetration, and the subject would doubtless prove an interest- ing one. A microscopic study of sections of the diseased root shows that the organism is most abundant in parenchymatous c
RMRDG9M2–. Parasitic fungi of Illinois / by T.J. Burrill. Fungi. Parasitic Fungi of Illinois. 395 roses, hops, gooseberries, raspberries, grapes,* and of many ornamental plants and trees, is caused by different species of this family. As their development is superficial, they are easily reached by remedial agents. Sulphur has long been successfully used to check the ravages of the grape mildew, and as a^ remedy for rose mildew in greenhouses. Its use is often indiscriminately recommended for any and all of these diseases, but the caution should be added, that, in some cases, the host plant suffers more
RMPG44RG–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. FUNGI IMPERKECTX (dEUTEROMYCETES) 261 groups of ASCOMYCETALES. Four families are included in this order, and these families include a considerable number of important genera of fungi, which specifically are the cause of important plant diseases. Phyllosticta is a genus, the species of which are confined to leaves, and they produce characteristic leaf spots on a great variety of plants. The specific name of the fungus is usually derived from that of the host plant attacked, as for exampl
RMRDR8G7–. Bacteria in relation to plant diseases. Bacteriology; Plant diseases. BACTERIA ON THE SURFACE OF PLANTS. 35 was alkaline. In case of fungus growths the reaction was acid. The constant occurrence of the bacteria or of the fungi in the interior of the water calyx in no way injures the host plant. The author ascribes the presence of bacteria or fungi to alkaline or acid secretions of the plant, but inasmuch as he seems to have determined the reaction only after the organisms had grown in the fluid, his con- clusion does not necessarily follow. These organisms are really still outside of the pla
RMPG4F88–. Minnesota plant diseases. Plant diseases. Chapter XV. Fungicides and Spraying Apparatus. Fungicides. By fungicides are understood those svibstances which are capable of destroying or prohibiting the growth of the spores or mycehum of fungi. Chemical solutions have proved of great value when sprayed upon diseased plants. Such a spray must not only not injure the plant, but must at the same time destroy or hold in check the parasite. It becomes evident, therefore, that such sprays are of greatest benefit in combating fungus parasites which live on the surface of the host plant, i. e., the epi-
RMRDDYA3–. The diseases of crops and their remedies : a handbook of economic biology for farmers and students. Plant diseases. MISCELLAirmVS CROPS. 147 group of which the " smnts " are important members. Fig. 49 represents a transverse section of a root with nodule. In very thin sections under high.power, the nodules are seen to be filled with hyphse and spores. The spores of this fungus are more or less v-shaped, and are formed by division of the protoplasmic contents of the hyphal filaments which ramify in the root-tissues of the host-plant. Unlike most of the members of the Ustila- ginece,
RMPG4ETD–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. j^o and as they mature, change to yellowish, then brown, and finally to a dark brown or black. The capsule is provided with thread- like appendages, which are dark brown in color and un- branched, and are interwoven with the threads of the mycelium. The mycelium sometimes forms brown spots on the leaves, and if present in quantity, may very seriously interfere with the nutrition of the leaf of the host plant and thereby occasion con- siderable damage. Each capsule contains a number of egg- shaped sacs, each of which contains
RMRDJG42–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. IOO FUNGOUS DISEASES OF PLANTS Morphology. Fungus and deformity. The parasite is sup- posed to gain entrance to the host plant during the swarmspore stage, or immediately upon leaving the swarmspore stage, there- fore in the amceboidal form. No observations, however, have been made relative to host penetration, and the subject would doubtless prove an interest- ing one. A microscopic study of sections of the diseased root shows that the organism is most abundant in parenchymatous c
RMPG3FTC–. A textbook of botany for colleges and universities ... Botany. 688 ECOLOGY. suberized. Branch veins and veinlets usually are much more numerous in xerophytic leaves than in the leaves of shade plants and hydrophytes. Parasitism and vascular development. — When Orobanche fasciciUata grows parasitically on an Artemisia root (fig. 1083), the latter often is stimulated to unusual development, the hadrome in particular being subject to extensive enlargement. In the haustoria of Melampyrum, tracheids develop only after attachment to a host plant.' Leaves infested by the parasitic fungus, Peronospo
RMRDWMJ7–. Principles of plant culture; an elementary treatise designed as a text-book for beginners in agriculture and horticulture. Horticulture; Botany. Plants as Affected by Fungous Parasites. 175 and pear, and the downy grape-vine mildew * may be held in check by applying a fungicide (321) to the host plant, to destroy the spores as they alight upon it. Vari- ous compounds of copper and of sulfur are destructive to the spores of fungi, and when properly applied, are harmless to the plant. The copper compounds are more generally satisfactory, since they have the greater ad- hesive power.. Fig. 78.
RMPG45DA–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 53 ual, it is living parasitically on the remainder of the host plant. That the broom itself is not injured, but rather stimulated, in its growth is seen, by the production of such numerous and large-sized branches. But the ultimate effect upon the whole. Fig. 23.—Witches'-broom on balsam fir, caused by a rust fungus (Aecidium elatinuin). The branches of the broom are vertical instead of horizontal, as are the normal, un- diseased branches in the right of the picture. Original. plant is injurious because the normal balance o
RMRD9MJ0–. A manual of weeds : with descriptions of all the most pernicious and troublesome plants in the United States and Canada, their habits of growth and distribution, with methods of control . Weeds. OONVOLVULACEAE (.CONVOLVULUS FAMILY) 325 dies; if there is such a plant, the parasite quickly twines about it, develops tiny, wart-like suckers at the point of contact, breaks connection with the earth, and thereafter "sponges its living," drawing from the host plant the food assimilated by the green leaves for its own growth. Con- sequently the Dodder needs no leaves and has none, the whol
RMPG4EP2–. Minnesota plant diseases. Plant diseases. Fig. 16S.—Potato blight. Early stages of the blight on the leaves. After Clinton. usually much branched, so that a miniature bush-like structure is produced and each branch terminates in a spore. These spores, as is true for most of the downy mildews, are in reality spore cases, for when placed in water they later give rise to a large number of swimming spores. When the latter come to rest they germinate into a tube which causes infection of the host plant. As far as is known at present, no winter spores are produced. The mycelium, however, is capabl
RMRDHK92–. A textbook of botany for colleges and universities ... Botany. 688 ECOLOGY. suberized. Branch veins and veinlets usually are much more numerous in xerophytic leaves than in the leaves of shade plants and hydrophytes. Parasitism and vascular development. — When Orobanche fasciciUata grows parasitically on an Artemisia root (fig. 1083), the latter often is stimulated to unusual development, the hadrome in particular being subject to extensive enlargement. In the haustoria of Melampyrum, tracheids develop only after attachment to a host plant.' Leaves infested by the parasitic fungus, Peronospo
RMPG430E–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. EFFECT OF PARASITIC FUNGI ON THE FORM OF HOST-PLANT. 25. the ovules become atrophied, whereas the rest of the flower is hypertrophied. Similarly with flowers of cowberry deformed by Uxobasidium. 2. Hypertrophy.âMany para- sitic fungi cause abnormal enlarge- ment or other malformation of plants which they attack. The simplest case of hypertrophy is seen in the enlargement of a uni- cellular plant as a result of an en
RMRDHED5–. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 144 SYSTEMATIC BOTANY. Pig. 260), or many-celled (as in Phragmidium). They rupture the epidermis and become exposed, but generally remain attached to their host-plant during the winter. In the spring, they germinate by sending out from each cell a jointed filament, called the promycelium. In small branches of the promycelium, small terminal cells, or sporidia, are formed. These are carried about by the wind, an
RMPG45CT–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 59 the rest of the plant. Then arise the carbuncle-like swellings of the leaves. If a kernel of the cob is attacked it increases perhaps tenfold in size. During this increase of size the fungus is also gaining strength and keeping pace with its partner plant-part, and when the proper moment has arrived for the formation of its spores it proceeds rapidly and utilizes all the extra food stored up by the swollen host plant-parts and de- stroys the latter rapidly. Such a parasite stimulates its host to unusual activity for a lon
RMRDE3C6–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. j^o and as they mature, change to yellowish, then brown, and finally to a dark brown or black. The capsule is provided with thread- like appendages, which are dark brown in color and un- branched, and are interwoven with the threads of the mycelium. The mycelium sometimes forms brown spots on the leaves, and if present in quantity, may very seriously interfere with the nutrition of the leaf of the host plant and thereby occasion con- siderable damage. Each capsule contains a number of egg- shaped sacs, each of which contains
RMPG0R79–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 110 PHYCOMYCETES. and the formation of zoosporangia take place in the cells of the living host-plant. In addition, spores are formed which have a resting period. {B) Only one kind of spore is formed; it has a resting period, and only proceeds to produce sori of zoosporangia after decay of the host-plant. (a) Ghrysochytrmm: protoplasm contains a yellow oil. (b) Leucochytrium: protoplasm colourless. Each of these divi
RMRDGAM0–. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. THALLOPHYTA. 669 Peronosporece.—Are mostly parasitic upon Flowering Plants, and the cause of many destructive diseases. They estabhsh themselves by means of a branching, tubular, non-septate mycelium which penetrates the intercellular system of the host- plant (c/. p. 56). They propagate asexually by means of unicellular sporangia borne on branched hyphse which project from the stomates, &c., of the host (c/. fig. 38V); these sporangia (or spores as they are sometimes termed) liberate on a moist
RMPG430Y–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 22 REACTION OF HOST TO PARASITIC ATTACK. of Other examples, since many of these will be referred to again in other chapters, particularly when hypertrophy is under consi- deration. § 5. EFFECT OF PARASITIC FUNGI ON THE FOEM OF THE HOST-PLANT. 1. Arrest of growth, and Atrophy. While a large number of fungi produce more or less extensive enlargement of parts of their host, others cause arrest of organs, crippling, imp
RMRE1N9Y–. College botany; structure, physiology and economics of plants. Botany. Fig. 126.—Albugo Candida showing the formation of the conidia spores just below the epider- mis of the host plant and also the antheridium and archegonium. swim for a few minutes m the moisture on the surface of the leaf, come to rest, lose their cilia and produce new hyphse which penetrate the leaf through the stomata. The oogonia and anthe- ridia are very similar to those of the Albugo. The late blight of the potato is in reality a mildew and is caused by a fungus (Phytophthora infestans). It is very similar to the grap
RMPG45PA–. Fungoid and insect pests of the farm. Agricultural pests. Fig. 48. Wingless and winged Aphides. (Magnified.) being produced at this time of the year. They also give rise to Hving young and serve to spread the aphides from one plant to another as one host plant soon becomes overcrowded. It is only at the end of the season that males are produced. They may be either winged or wingless and are born together with the females. Pairing takes place and the fertilized females do not produce hving young but lay eggs. These do not hatch out at once but are capable of resisting the cold weather of wint
RMRE0NH7–. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 144 SYSTEMATIC BOTANY. Fig. 260), or many-celled (as in Phragmidium). They rupture the epidermis and become exposed, but generally remain attached to their host-plant during the winter. lu the spring, they germinate by sending out from each cell a jointed filament, called the promycelium. In small branches of the promycelium, small terminal cells, or sporidia, are formed. These are carried about by the wind, an
RMPG4FGW–. Minnesota plant diseases. Plant diseases. Chapter X. Fungi. Kinds of Fungi. Sac Fungi, Black knot and allies {Dothideacece in part). One of the most conspicuous fungi of Minnesota is the so-called black- knot fungus of cultivated and wild cherries and plums. In the mature stage of the fungus, its host-plant branches carry black knot-like swellings and distortions, which are very conspicuous. These knots so interfere with the nutrition of the branch beyond that the latter usually dies off in a year or two. The fungus then gradually works its way downward to the intersection of another branch,
RMRDEX8J–. Minnesota plant diseases. Plant diseases. 212 Minnesota Plant Diseases. without injury to the host plant. Only the best-known and well-established formulae will be considered here. For de- tailed accounts of the action on specific diseases, the special portion of this work should be consulted, as also the experi- ment station bulletins of the Department of Agriculture. A great many of the bulletins of the Department of Agriculture and of the various Experiment Stations have been consulted in compiling these formulae. These may be referred to for fur- ther detail. The value of spraying in agr
RMPG431F–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. MODE OF LIFE OF THE PARASITIC FUNGI. 9 I can however hardly regard as parasites, fungi like these which live on an accidental outflow from plants or plant-cells, even though they regularly frequent places where an outflow is to be expected. They exert no influence on the host-plant, and they are nourished by substances which can no longer be regarded as belonging to the host. I would rather include them amongst non-
RMRDYFY8–. A textbook of botany for colleges and universities ... Botany. 82 MORPHOLOGY The basidiospore develops a mycelium that penetrates the young seedling of the host plant. (b) Uredinales General character. — These are the well-known rusts, all of them being destructive parasites, whose mycelia live in the intercellular spaces of higher plants, especially in the leaves. The best-known form is Puccinia graminis, one of the wheat rusts, and an outhne of its life history will serve as an illustration of the group. Wheat rust. —The mycelium traverses the tissues of the young wheat plant, and during t
RMPFXCM1–. The care of trees in lawn, street and park, with a list of trees and shrubs for decorative use. Trees; Trees. CHAPTER VI CONTROL OF PARASITES E have seen in previous chapters the character and effect of parasitic attacks on trees, how they are recognized, and also that their dam- age can be checked and reduced to a large extent by the mere care of keeping the trees in vigor. We are now to consider specific methods of controlling these fungus and insect injuries. Fungus Parasites. The fundamental principle in com- bating fungus attacks is to prevent the infection of the host plant by the spor
RMRDE24A–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. FUNGI IMPERKECTX (dEUTEROMYCETES) 261 groups of ASCOMYCETALES. Four families are included in this order, and these families include a considerable number of important genera of fungi, which specifically are the cause of important plant diseases. Phyllosticta is a genus, the species of which are confined to leaves, and they produce characteristic leaf spots on a great variety of plants. The specific name of the fungus is usually derived from that of the host plant attacked, as for exampl
RMPG4303–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. EFFECT OF PARASITIC FUNGI ON THE FORM OF HOST-PLANT. 31 Somewhat doubtful cases are the outgrowths resembling aerial roots which arise on Laurus canariensis attacked by Eocdbasidium lauri. Geyler, their discoverer, regarded them as deformed stem- shoots, but they resemble rather the galls of the alpine-rose. § 6. EFFECT OF PARASITIC FUNGI ON CELL-CONTENTS. The most common and, at the same time, most apparent effect
RMRDJ6B4–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 3i8 FUNGOUS DISEASES OF PLANTS spreads to the stem and leaves. Entrance to the tubers is gained, therefore, as a rule, through the stems upon which they are borne. The vascular system of the host plant is discolored, al- though frequently the tubers are not seriously injured externally until after they are gathered. In storage, however, the fungus progresses rapidly, blackening the vascular ring. At this stage the disease is only made apparent in the tubers by cutting them crosswis
RMPG3W5B–. A monograph of lichens found in Britain; being a descriptive catalogue of the species in the herbarium of the British Museum. Lichens. Plate 36. OBRYZUM DOLICHOTBRON Nyl. a. Host plant (Colletna) with parasite, b. Lobe of Collema with perithecia of parasite, c. Vertical section of perithecium and of host thallus. d. Asous. e. Spores.. 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.. British Museum (Natural History). Dept.
RMRDEX93–. Minnesota plant diseases. Plant diseases. Chapter XV. Fungicides and Spraying Apparatus. Fungicides. By fungicides are understood those svibstances which are capable of destroying or prohibiting the growth of the spores or mycehum of fungi. Chemical solutions have proved of great value when sprayed upon diseased plants. Such a spray must not only not injure the plant, but must at the same time destroy or hold in check the parasite. It becomes evident, therefore, that such sprays are of greatest benefit in combating fungus parasites which live on the surface of the host plant, i. e., the epi-
RMPG4EHE–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 389 The fungus threads, which are found in the swollen parts of the host plant and which cause the stimulation, whereby the increase of growth or swelling of the stem takes place, form their winter rust-spores inside of the cells of the epidermis of. Fig. 206.—Sunflower rust. Winter and summer spore clusters on the leaf of <l sunflower. Original. the host. This epidermis is much altered on account of the action of the fungus. Its cells have thin, instead of thick, outer walls, and are much increased in size. These spores
RMRDDWPM–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 102 SYMBIOSIS. much and become club-shaped or dichotomously branched bodies without power of division, which may be designated " bacteroids." ^ Brunchorst found the contents of the bacteroids. Fig. 23.—Rhizobium teguminosarum, Root*tubercles on Robinia Fseudacacia (V. Tubeuf phot.) to disappear at the time of the fruit-formation of the host- plant. A small number of microbe-bodies still remain, according t
RMPG4BFB–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. CEYPTOMYCES. 247 especially Salix incana, but also on ^S*. purpurea. When the black apothecial cushions break out through the bark, the twigs of the host-plant are frequently still green and leaf-clad. The apothecia originate in the lower bark and so loosen the epidermal layers as to cause the appearance of yellow spots. Black centres appear in the spots, due to the formation of a. Fig. 132.—Cryptomyces maximum. 1,
RMRDE582–. Fungoid and insect pests of the farm. Agricultural pests. Fig. 48. Wingless and winged Aphides. (Magnified.) being produced at this time of the year. They also give rise to Hving young and serve to spread the aphides from one plant to another as one host plant soon becomes overcrowded. It is only at the end of the season that males are produced. They may be either winged or wingless and are born together with the females. Pairing takes place and the fertilized females do not produce hving young but lay eggs. These do not hatch out at once but are capable of resisting the cold weather of wint
RMPG4BE1–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. SCLEROTINIA. 259 cowberry shoots, the stomata being always avoided. In less than three weeks conidia are produced. The mode in which the germ-tubes attack the host-plant is very remarkable. Woronin says: " The germ-tubes developed from the ascospores grow inwards towards the vascular bundles of the host-plant and enter them; then they continue to develop, but now in the opposite direction from the interior of .
RMRDNEHK–. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. MISTLETOES AND LORANTHUSES. 207 to stick with the radicle of the seedling pointing away trom the branch; the whole axis of the embryo curving towards the surface of the bark in a very striking manner. Thus the radicle always reaches the bark, and having done so it becomes adpressed and cemented to its surface, spreads itself out in the form of a doughy mass, and so develops into a regular attachment-disc. From its centre a slender pro- cess now grows into the bark of the host-plant, piercing the latt
RMPG0R7P–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 102 SYMBIOSIS. much and become club-shaped or dichotomously branched bodies without power of division, which may be designated " bacteroids." ^ Brunchorst found the contents of the bacteroids. Fig. 23.—Rhizobium teguminosarum, Root*tubercles on Robinia Fseudacacia (V. Tubeuf phot.) to disappear at the time of the fruit-formation of the host- plant. A small number of microbe-bodies still remain, according t
RMRDDWXC–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. EFFECT OF PARASITIC FUNGI ON THE FORM OF HOST-PLANT. 31 Somewhat doubtful cases are the outgrowths resembling aerial roots which arise on Laurus canariensis attacked by Eocdbasidium lauri. Geyler, their discoverer, regarded them as deformed stem- shoots, but they resemble rather the galls of the alpine-rose. § 6. EFFECT OF PARASITIC FUNGI ON CELL-CONTENTS. The most common and, at the same time, most apparent effect
RMPG45ED–. Minnesota plant diseases. Plant diseases. 20 Minnesota Plant Diseases. ularly perennial. The latter include both saprophytes and parasites. The fairy-ring mushrooms are good examples of the former, while of the latter, illustrations are found in those rust funffi which attack balsam fir and other cone-bearing plants and form witches' brooms. The mycelium of the fungus caus- ing smut of grains is of a peculiar kind. It often finds its way into the host plant when the latter is very young and tender, and continues to grow in the delicate growing parts and dies. Fig. 8.—Fairy rings of a mushroo
RMRDJDTA–. A monograph of lichens found in Britain; being a descriptive catalogue of the species in the herbarium of the British Museum. Lichens. Plate 36. OBRYZUM DOLICHOTBRON Nyl. a. Host plant (Colletna) with parasite, b. Lobe of Collema with perithecia of parasite, c. Vertical section of perithecium and of host thallus. d. Asous. e. Spores.. 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.. British Museum (Natural History). Dept.
RMPFY1BH–. 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. 48 ENCYCLOPEDIA OF PRACTICAL HORTICULTURE them. When full grown the stem-mother is purplish-gray covered with a sparse white bloom and is almost as broad as long. The lice of the third generation are full grown in early June and are all winged pinkish individuals. They migrate in a body to an alternate host- plant, as yet unknown. In the fall a g
RMRDDWM8–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. CYSTOPUS. 125 Besides conidia, spherical oospores may also be present; these are generally produced on the stems of the host-plant, but also on flower-stalks and ovary-walls. The spherical conidia arise in simple chains on short coni- diophores, and are loosely connected by tiny intermediate cells. The conidial cushions rupture the epidermis and the ripe conidia fall off to produce biciliate swarming cells (Fig. 34)
RMPG3DP2–. Plant studies; an elementary botany. Botany. THE NUTKITIoN OF I'LAXTS 161 oaks and tlu'ir allies, etc. (Figs. 140, 1.50). Tlie delicate branching filaments (hypha?) of the fungus spread through the soil, wrap the rootlets with a mesh of hyplux', and pene- trate into the cells. It seems clear that the fungus obtains food from the rootlet as a parasite; but it is also thought that the hyphal threads, spreading widely through the soil, are of great service to the host plant in aiding the rootlets in absorl)ing. If this be true, there is mutual ad- vantage in the association, for the small amoun
RMRDGX69–. The diseases of crops and their remedies : a handbook of economic biology for farmers and students. Plant diseases. 52 DISEASES OF CROPS. 22) is examined beneath the microscope,^ the mycelium of the fungus will be seen ramifying among the cells of the leaf. "Wherever the mycelium comes in contact with the cells of the host-plant, they become discoloured. This is. Fig. 22.^PoTATO FcNans {Peronospora infestans). A to B. Transverse section of potato leaf, showing mycelium (spawn) of fungup. A. Lower surface with two stomata (C) and conidiophores passing tiirough them. D. Conidium (spore).
RMPG4FDA–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 165 nest broom of the red cedar and the great bush- like brooms of the bal- sam fir. These have al- ready been described as stimulated portions of the host plant which, with the fungus parasite, live in partnership at the expense of the neighbor- ing parts of the host. Besides this deforming power of many rusts these parasites are injuri- ous in the stealing of nourishment which they accomplish at the ex- pense of the host and in the wounding of plant parts. The host, as a re- sult, becomes impover- ished and may finally en-
RMRD8FJR–. The care of trees in lawn, street and park, with a list of trees and shrubs for decorative use. Trees; Trees. CHAPTER VI CONTROL OF PARASITES E have seen in previous chapters the character and effect of parasitic attacks on trees, how they are recognized, and also that their dam- age can be checked and reduced to a large extent by the mere care of keeping the trees in vigor. We are now to consider specific methods of controlling these fungus and insect injuries. Fungus Parasites. The fundamental principle in com- bating fungus attacks is to prevent the infection of the host plant by the spor
RMPG4ADB–. Foundations of botany. Botany; Botany. BOOTS 39 it may readily be transferred to moderately damp soil, and that the whole plant presents curious modifications when made to grow in earth instead of water. 51. Parasitic Roots.' — The dodder, the mistletoe, and a good many other parasites, live upon nourishment which they steal from other plants, called hosts. The parasitic. Fig. 15. — Aerial Adyentitlous Roots of the Ivy. roots, or haustoria, form the most intimate connections with the interior portions of the stem or the root, as the case may be, of the host-plant on which the parasite fasten
RMRDE4CH–. Minnesota plant diseases. Plant diseases. Chapter X. Fungi. Kinds of Fungi. Sac Fungi, Black knot and allies {Dothideacece in part). One of the most conspicuous fungi of Minnesota is the so-called black- knot fungus of cultivated and wild cherries and plums. In the mature stage of the fungus, its host-plant branches carry black knot-like swellings and distortions, which are very conspicuous. These knots so interfere with the nutrition of the branch beyond that the latter usually dies off in a year or two. The fungus then gradually works its way downward to the intersection of another branch,
RMPG0R5P–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. CYSTOPUS. 125 Besides conidia, spherical oospores may also be present; these are generally produced on the stems of the host-plant, but also on flower-stalks and ovary-walls. The spherical conidia arise in simple chains on short coni- diophores, and are loosely connected by tiny intermediate cells. The conidial cushions rupture the epidermis and the ripe conidia fall off to produce biciliate swarming cells (Fig. 34)
RMRDEXHB–. Minnesota plant diseases. Plant diseases. Minnesota Plant Diseases. 165 nest broom of the red cedar and the great bush- like brooms of the bal- sam fir. These have al- ready been described as stimulated portions of the host plant which, with the fungus parasite, live in partnership at the expense of the neighbor- ing parts of the host. Besides this deforming power of many rusts these parasites are injuri- ous in the stealing of nourishment which they accomplish at the ex- pense of the host and in the wounding of plant parts. The host, as a re- sult, becomes impover- ished and may finally en-
RMPG430P–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 24 REACTION OF HOST TO PARASITIC ATTACK. True atrophy is best seen in those cases where flower-forma- tion is suppressed. This effect of parasitic fungi on their host is by no means uncommon, the fungus alone reproducing itself, while the assimilating host-plant remains sterile. This atrophy is found not only in annual plants, but also in those where the symbiosis might be designated as perennial. The last-mentioned
RMRDWACP–. Textbook of botany. Botany. ROOTS AND THEIR USES l8i new suckers are formed from time to time, which, Hke the sucker formed in the first season, grow inward through the tissues of the host until they reach the wood. Thus, while the suckers of the dodder take materials both from the bast and from the wood, the suckers of the mistletoe make con- nection only with the wood of the host, whence they absorb water and simple salts. Having green leaves, the mistletoe takes carbon dioxid from the air and manufactures for itself the more complex foods which the dodder takes from the host plant. The Am
RMPG4EK2–. Minnesota plant diseases. Plant diseases. 362 Minnesota Plant Diseases. palisade fashion on the surface of the pocket. Each sac contains about eight spores, which on germination may directly cause in- fection of a host plant. The fungus of this disease is very closely related to the peach leaf-curl fungus and to others forming witches'-broom on birch, alder and cherry trees. It is a sac- fungus with an arrangement of sacs similar to that in the true cup fungi, but has no true cup, since the sacs occur directly on the tissues of the host.. Fig. 193.—Plum pockets. These plums are devoid of sto
RMRDEE5T–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 110 PHYCOMYCETES. and the formation of zoosporangia take place in the cells of the living host-plant. In addition, spores are formed which have a resting period. {B) Only one kind of spore is formed; it has a resting period, and only proceeds to produce sori of zoosporangia after decay of the host-plant. (a) Ghrysochytrmm: protoplasm contains a yellow oil. (b) Leucochytrium: protoplasm colourless. Each of these divi
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