RF2G21MBY–Lichen cladonia coniocraea and moss on tree bark in autumn forest. Black and white photo.
RMRPY16W–. Hawaiian Fungi. Fungi. Stevens—Hawaiian Fungi 143 A few immature, subepidermal pycnidia of very different character, with definite ostioles, were found in one of the spots bearing the Leptothyrium,. 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.. Stevens, Frank Lincoln, 1871-1934. Honolulu, Hawaii : The Museum
RMPG4BFN–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. RHYTISMA. 245 eight needle-shaped unicellular spores; pycnidia (spermogonia) with little unicellular conidia are also formed. The fungus attacks leaves of sycamore {Acer Pseudoplatanus), the black spots making their appearance in September. The apothecia ripen on the ground during the following summer.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea
RMRE1GM6–. Fungi; their nature, influence, and uses;. Fungi. 62 FUNGI. cated, and these are no longer regarded so mncli as species of Sendersonia or Diplodia as the pycnidia of Sph(jBria. Other and more minute perithecia, containing minute, slender stylospores in great numbers, formerly classed wiGa. ApospJiceria, Phoma, &c., but are now I'ecognized as spermogonia containing the spermatia of Splicerite. How these influence each other, when and under what circumstances the spermatia are instrumental in impregna- tion of the sporidia, is still matter of mystery. It is clear, how- ever, that in all tl
RMPG3R35–. Manual of fruit diseases . Fruit. BLACKBERRY DISEASES 167 But the successive activities of Scptoria Riibi have not been care- fully studied ; this is probably due to the fact that the disease which it produces has never been of great economic importance. The mycelium of the fungus growing in local areas within the leaf-tissues causes the color changes and finally their death. The fungus forms fruit- ing bodies — pycnidia — just beneath the upper surface of the cuticle. These, as the^' mature, break through the cuti- cle and stand exposed over the affected area. Within the pycnidia spores are
RMRDX2X0–. Lichens. Lichens. 200 REPRODUCTION The three last named types of sporophores represent Nylander's section of arthrosterigmata. Steiner has followed Nylander in also arranging the various forms into two leading groups. The first, characterized by the secondary branch or "sterigma," he designates "exobasidial"; the second, comprising the three last types in which the spores are borne directly on the cells of the sporophore or on very short processes, he describes as " endo- basidial." Steiner also introduces a new term, fulcrum, for the sporophore. The pycnidia in
RMPG3GF8–. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. CHAPTER V.—COMPARATIVE REVIEW.—ASCOMVCETES. 243 his Peziza benesuada (Fig. 115); similar organs occupy the margin of the platter- shaped tube-bearing hymenia of Cenangium Frangulae, Tul. Small round cells incapable of germination, which will be noticed again in a subsequent page, are said by Brefeld * to be sometimes abscised from the ramifications of the paraphyses in Peziza Sclerotiorum. The second place where these doubtful' spermatia' occur is in the pycnidia of c
RMRDC1HE–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. RHYTISMA. 245 eight needle-shaped unicellular spores; pycnidia (spermogonia) with little unicellular conidia are also formed. The fungus attacks leaves of sycamore {Acer Pseudoplatanus), the black spots making their appearance in September. The apothecia ripen on the ground during the following summer.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for rea
RMPG4B3H–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 364 UREDINEAK. direction; their sori form dark spots which break out from beneath the epidermis. The yellow uredospores have a coat beset with fine spines, and are given off from sori which may or may not be enclosed in a peridium. The sori of the aeeidium-stage have no peridium, and are known under the generic name of Caeoma; they frequently occur on other hosts than those of the teleutospores. Pycnidia are produce
RMRDCXN7–. Manual of fruit diseases . Fruit. BLACKBERRY DISEASES 167 But the successive activities of Scptoria Riibi have not been care- fully studied ; this is probably due to the fact that the disease which it produces has never been of great economic importance. The mycelium of the fungus growing in local areas within the leaf-tissues causes the color changes and finally their death. The fungus forms fruit- ing bodies — pycnidia — just beneath the upper surface of the cuticle. These, as the^' mature, break through the cuti- cle and stand exposed over the affected area. Within the pycnidia spores are
RMPG3YH6–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 260 FUNGOUS DISEASES OF PLANTS are produced within which areas the pycnidia may be found. Cuttings may also be affected. The fungus. The pycnidial stage is a characteristic Phoma or Phyllosticta, ioo to 120/i in diameter, as shown in Fig. 113. These are distributed over the affected surfaces, and produce abundant conidia, which are hyaline, obovoidal, frequently trun- cated at the apex, measuring 10.5-13.5 X 5-6/*. The conidia are appendaged, and they are expelled from the perithec
RMRDCRW5–. Comparative morphology and biology of the fungi, mycetozoa and bacteria . Plant morphology; Fungi; Myxomycetes; Bacteriology. CHAPTER V.—COMPARATIVE REVIEW.—ASCOMVCETES. 243 his Peziza benesuada (Fig. 115); similar organs occupy the margin of the platter- shaped tube-bearing hymenia of Cenangium Frangulae, Tul. Small round cells incapable of germination, which will be noticed again in a subsequent page, are said by Brefeld * to be sometimes abscised from the ramifications of the paraphyses in Peziza Sclerotiorum. The second place where these doubtful' spermatia' occur is in the pycnidia of c
RMPG4B54–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 352 UREDINEAE. aecidia (Aec. parnassiae Schlecht.) on Parnassia palustris.. Spermogonial pycnidia are unknown. P. sdrpi D. C. (Britain). Uredo- and teleutospores on Scirpus; aecidia, according to Chodat, = Aec. nymphaeoides on Nymphaea, Nuphar, and Lim- nanthemmn, nymphaeoides.. Fig. 186.—Puccinia suaveolens on Cirsium arveTise. The plants ai-e abnormally slongated; the leaves have remained smaller and simpler, and
RMRDJ657–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECT! 359 The Kieffer is practically exempt. In any case, however, the fungus may be readily controlled with Bordeaux. The spots on the leaves are few or numerous, angular, and the size varies greatly with the variety. Three fairly well differentiated zones of color are shown in an affected spot: at the center it is ashen gray, and within this area appear on either surface the minute pycnidia; the next outer zone, or area, is brown, or black in very young leaves; and sur
RMPG4B1G–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 378 UREDINEAE. and small yellow pycnidia are produced during July or August. The aecidia follow from August till September, occupying yellow zones on the otherwise green needles; their white peridia project as much as 2 mm. above the surface of the needle, and dehisce by rupture of the apex. The aecidiospores are formed in large numbers and, carried by wind, reach leaves and shoots of alpine-rose where they immediat
RMRDJ63W–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECTI 363 Septoria Ribis Desm.1 is common upon various species of Ribes. With respect to the economic hosts many varieties of both currants and gooseberries are subject to attack. Large spots with pale centers and brown borders are produced (Fig. 181). These are readily distinguished from those produced by the anthracnose (cf. Fig. 79) by the large size, the well-defined outline, and the pale central dead area. The pycnidia are found in small groups at the centers of the
RMPG3W0W–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. ASCOCHYTA. 473. U8 this fungus is injurious to Pisum sativum, Phaseolus vulgaris, Vicia sativa, etc. It causes spots on leaves and pods, followed by- drying up of the former and deformation of the latter. The pycnidia appear as tiny points on the spots, and give out bicellular cylindrical conidia. As. Boltshauseri Sacc.^ This species was first observed in Switzerland on bean {Plia- seolus vulgaris). Leaves of all ag
RMRDD7MC–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fig. 197.—Caeonia pinitwquum. Portion of Ctteoma-patch (enlarged). /, Cortical cells partially absorbed or muck compressed ; 6, baaidia from which spores (c) are abjointed in succession: the younger with delicate walls and separated by membranous lamellae, which disappear on formation of the spore-coats (d). (After R. Hartig.) The pycnidia are produced at end of May or beginning of June, between the epidermal cell-w
RMPG3NWM–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECT! 359 The Kieffer is practically exempt. In any case, however, the fungus may be readily controlled with Bordeaux. The spots on the leaves are few or numerous, angular, and the size varies greatly with the variety. Three fairly well differentiated zones of color are shown in an affected spot: at the center it is ashen gray, and within this area appear on either surface the minute pycnidia; the next outer zone, or area, is brown, or black in very young leaves; and sur
RMRDE3FF–. Diseases of economic plants . Plant diseases. 146 DISEASES OF ECONOMIC PLANTS be of serious import, although its increase at any time under favorable climatic conditions may place it among the im- portant plant enemies. CRANBERRY' Scald, blast (Guignardia Vacdnii Shear). — The fruits are attacked as soon as the blossom falls, or even the. Fig. 62. — Cranberry scald and blast. After Shear. blossom itself may be blighted. The affected berry shrivels, turns black, and is covered with pycnidia. From such fruits the disease spreads to other fruits and to the leaves. In some bogs as much as 50 per
RMPG3NTP–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. FUNGI IMPERFECTI 363 Septoria Ribis Desm.1 is common upon various species of Ribes. With respect to the economic hosts many varieties of both currants and gooseberries are subject to attack. Large spots with pale centers and brown borders are produced (Fig. 181). These are readily distinguished from those produced by the anthracnose (cf. Fig. 79) by the large size, the well-defined outline, and the pale central dead area. The pycnidia are found in small groups at the centers of the
RMRDJF5B–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 260 FUNGOUS DISEASES OF PLANTS are produced within which areas the pycnidia may be found. Cuttings may also be affected. The fungus. The pycnidial stage is a characteristic Phoma or Phyllosticta, ioo to 120/i in diameter, as shown in Fig. 113. These are distributed over the affected surfaces, and produce abundant conidia, which are hyaline, obovoidal, frequently trun- cated at the apex, measuring 10.5-13.5 X 5-6/*. The conidia are appendaged, and they are expelled from the perithec
RMPG3TXF–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 476 FUNGI IMPERFECTI. of the shoots, aud either rupture the epidermis or grow out from the leaf-scar cushions (Fig. 297). The couidia are abjointed from filamentous conidiophores inside the pycnidia, and emerge as tendril-like structures. They are two-celled, small, cylindrical, and pointed at both ends. Germination takes place easily in water, and the disease spreads rapidly over the young developing shoots during
RMRDCYCF–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 378 UREDINEAE. and small yellow pycnidia are produced during July or August. The aecidia follow from August till September, occupying yellow zones on the otherwise green needles; their white peridia project as much as 2 mm. above the surface of the needle, and dehisce by rupture of the apex. The aecidiospores are formed in large numbers and, carried by wind, reach leaves and shoots of alpine-rose where they immediat
RMPG44RC–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 262 MYCOLOGY spores in Phoma are colorless and unicellular. The pycnidia are black with a terminal pore and depressed in the tissues of the host. The genus is arbitrarily limited to those species in which the spores are less than 15/4, for the larger spored forms have been placed in the genus Macrophoma. The most important species from the pathologic viewpoint are out of the iioo species recognized the^oUowing: Phoma beta is the cause of the heart rot and blight of beets. Phoma batata p
RMRDD7MT–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 364 UREDINEAK. direction; their sori form dark spots which break out from beneath the epidermis. The yellow uredospores have a coat beset with fine spines, and are given off from sori which may or may not be enclosed in a peridium. The sori of the aeeidium-stage have no peridium, and are known under the generic name of Caeoma; they frequently occur on other hosts than those of the teleutospores. Pycnidia are produce
RMPG4B36–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fig. 197.—Caeonia pinitwquum. Portion of Ctteoma-patch (enlarged). /, Cortical cells partially absorbed or muck compressed ; 6, baaidia from which spores (c) are abjointed in succession: the younger with delicate walls and separated by membranous lamellae, which disappear on formation of the spore-coats (d). (After R. Hartig.) The pycnidia are produced at end of May or beginning of June, between the epidermal cell-w
RMRDX3G6–. Lichens. Lichens. i6o REPRODUCTION I. DISCOLICHENS a. Carpogonia of Gelatinous Lichens. Stahl's^ work on various Collemaceae followed on the same lines as that of Fuisting. The first species selected by him for examination, Collema (Leptogiufn) microphylluni, is a gelatinous lichen which grows on old trunks of poplars and willows. It has a small olive-green thallus which, in autumn, is crowded with apothecia; the spermogones or pycnidia appear as minute reddish points on the edge of the thallus. Within the thallus, and midway between the upper and lower surface, there arises, as a branch fro
RMPG4EXP–. Diseases of economic plants . Plant diseases. 146 DISEASES OF ECONOMIC PLANTS be of serious import, although its increase at any time under favorable climatic conditions may place it among the im- portant plant enemies. CRANBERRY' Scald, blast (Guignardia Vacdnii Shear). — The fruits are attacked as soon as the blossom falls, or even the. Fig. 62. — Cranberry scald and blast. After Shear. blossom itself may be blighted. The affected berry shrivels, turns black, and is covered with pycnidia. From such fruits the disease spreads to other fruits and to the leaves. In some bogs as much as 50 per
RMRDE242–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 262 MYCOLOGY spores in Phoma are colorless and unicellular. The pycnidia are black with a terminal pore and depressed in the tissues of the host. The genus is arbitrarily limited to those species in which the spores are less than 15/4, for the larger spored forms have been placed in the genus Macrophoma. The most important species from the pathologic viewpoint are out of the iioo species recognized the^oUowing: Phoma beta is the cause of the heart rot and blight of beets. Phoma batata p
RMPG4EX4–. Diseases of economic plants . Plant diseases. SMALL FBUITS 153 although sometimes irregular in outline, generally about 3 mm. in diameter. In the center of the brown or gray discolored area very minute pycnidia may be seen in the case of septoriose; hyphse in the case of cercosporose. Defoliation, often serious to the plant, results.. Fig. 65.—Currant anthracnose. After Stewart and Eustace. The Bordeaux mixture is far superior to ammoniacal copper carbonate for these diseases. Five applications at ten- to fourteen-day intervals are needed, beginning as soon as the leaves are open. Anthracnos
RMRDD7RB–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 352 UREDINEAE. aecidia (Aec. parnassiae Schlecht.) on Parnassia palustris.. Spermogonial pycnidia are unknown. P. sdrpi D. C. (Britain). Uredo- and teleutospores on Scirpus; aecidia, according to Chodat, = Aec. nymphaeoides on Nymphaea, Nuphar, and Lim- nanthemmn, nymphaeoides.. Fig. 186.—Puccinia suaveolens on Cirsium arveTise. The plants ai-e abnormally slongated; the leaves have remained smaller and simpler, and
RMPG4AN8–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 418 UREDINEAE. Caeoma. Caeoma abietis-pectinatae Eeess.^ The aecidiospores may be found on the lower surface of young needles of silver fir; the aecidia are yellow elongated cushions situated on either side of the needle mid-rib, and are without peridia. Pycnidia (spermogonia) are pro- duced before the aecidia. The mycelium is septate and intercellular with few haustoria. I have found the fungus fairly abundant on t
RMRDC13H–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 418 UREDINEAE. Caeoma. Caeoma abietis-pectinatae Eeess.^ The aecidiospores may be found on the lower surface of young needles of silver fir; the aecidia are yellow elongated cushions situated on either side of the needle mid-rib, and are without peridia. Pycnidia (spermogonia) are pro- duced before the aecidia. The mycelium is septate and intercellular with few haustoria. I have found the fungus fairly abundant on t
RMPG46F6–. The fungi which cause plant disease . Plant diseases; Fungi. 242 THE FUNGI WHICH CAUSE PLANT DISEASE oculations under all conceivable conditions, failed utterly of posi- tive results. From the Caucasus Prillieux and Delacroix "^ have described a Guignardia causing a black rot of grapes which is regarded as distinct from the usual American form, differing both in the peri- thecial and conidial stages. This is called G. baccae (Cav.) Jacz. Its conidial form Phoma reniformis eventually covers the whole berry with pustules. Two kinds of pycnidia are described. G. vaccinii Sh."^- "
RMRDE3EJ–. Diseases of economic plants . Plant diseases. SMALL FBUITS 153 although sometimes irregular in outline, generally about 3 mm. in diameter. In the center of the brown or gray discolored area very minute pycnidia may be seen in the case of septoriose; hyphse in the case of cercosporose. Defoliation, often serious to the plant, results.. Fig. 65.—Currant anthracnose. After Stewart and Eustace. The Bordeaux mixture is far superior to ammoniacal copper carbonate for these diseases. Five applications at ten- to fourteen-day intervals are needed, beginning as soon as the leaves are open. Anthracnos
RMPG4E8X–. Diseases of economic plants . Plant diseases. TREES AND TIMBER 433 gray border. The spots, from 3-6 mm. in diameter, often coalesce to form large blotches which are fragile, sometimes dropping from the leaf. Young leaves develop poorly and are deformed, while severe infection may cause complete defoliation of the tree.. Fig. 188.- ' Cedar apple." gall of the rust fungus. Original. Macrosporiose (Macrosporium Catalpw Ell. & Mart.).— This spot is scarcely distinguishable from phyllostictose except through the absence of pycnidia and the presence of a scant quantity of Ijlack mold. Pow
RMRDCY4T–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 476 FUNGI IMPERFECTI. of the shoots, aud either rupture the epidermis or grow out from the leaf-scar cushions (Fig. 297). The couidia are abjointed from filamentous conidiophores inside the pycnidia, and emerge as tendril-like structures. They are two-celled, small, cylindrical, and pointed at both ends. Germination takes place easily in water, and the disease spreads rapidly over the young developing shoots during
RMPG45RF–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 509 confluent, marginally fimbriate, the radiating fibers arachnoid, white, distinctly branched; pycnidia tuberculariform, scattered or confluent, black; conidia oblong, constricted, 18-20 x 5. /i; conidiophores short. This fungus was first described in 1826. It is common on rose leaves. The mycelium is in part subcuticular, in part deeper. The subcuticular part is visible through the cuticle, consisting of radiate strands each composed of several parallel hyphae. From this mycelium branches pene
RMRDCY56–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. ASCOCHYTA. 473. U8 this fungus is injurious to Pisum sativum, Phaseolus vulgaris, Vicia sativa, etc. It causes spots on leaves and pods, followed by- drying up of the former and deformation of the latter. The pycnidia appear as tiny points on the spots, and give out bicellular cylindrical conidia. As. Boltshauseri Sacc.^ This species was first observed in Switzerland on bean {Plia- seolus vulgaris). Leaves of all ag
RMPG401J–. Manual of fruit diseases . Fruit. 258 MANUAL OF FRUIT DISEASES trunks. When affected canes are saved for bearing wood, the fungus spreads into the arm. As a rule the mycelium does not extend into the roots. Pycnidia are developed abundantly on affected canes and on green and ripening berries (Fig. 70). They appear on the former early in the spring, and may be found on canes se'erely infected the previous year or occasionally on the current year's growth. The pycnidia mature shortly after the buds burst in the spring, and the pycnospores ooze out in long, reddish yellow coils, each contain-
RMRE1N8H–. College botany; structure, physiology and economics of plants. Botany. Fig. 133.—Wheat rust; (a) cross-section showing the secial stage on the .barberry; (6) urediniospore; (c) teliospore: (d), germinating' tehospore showing sporidia; (e) pycnidia. The Profo-hasidiomycetes is divided into the Usitila-ginales or smuts and the Uredinales or rusts. The smuts (Fig. 132) attack many plants, but may be characterized by the com smut, TJstila-go maydis. The mycelium works within the host and finally causes swollen, tumor-like growths, which may ap'pear on any part of the plant. When mature, these ma
RMPG14M5–. Chestnut blight. Chestnut blight; Chestnut. Endothia Canker of Chestnut SS9 They are closely crowded together, so that in cross section they appear to make up a pseudoparenchymatous tissue. These cells are more densely filled with protoplasm, and contain more pigment, than the interior cells. Pycnidia On smooth-bark, young cankers, especially in the summer, the outer cork layer is raised in numerous little blisters, with slender, yellow, waxy tendrils curling from their ruptured apices (Plate XXXVIII, Fig. i). Under each blister is a single somewhat globose pycnidiimi, surrounded by a scanty
RMRDC1XT–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fig. 99.—Cucurbitaria Idburni. A, Stroma with pycnidia containing minute unicellular conidia. B, One of the large smooth pycnidia. (After v. Tubeuf.) The mature perithecia have a peridium consisting of a loose pseudoparenchyma with a rough warty exterior and a pore set in a distinct depression (Fig. 100.) The paraphyses are long, strong threads, often branched, and between them arise the long cylindrical asci with r
RMPG3NXH–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 354 FUNGOUS DISEASES OF PLANTS effuse colonies, the aerial portions of which are at first gray, be- coming darker with age. The pycnidia may sometimes be pro- duced in agar and also upon various solid media in tube cultures. Control. Preventive meas- ures have not been carefully worked out. Under ordinary circumstances orchards in good condition will suffer least. Advantage may also be de- rived from treating the limbs and trunk thoroughly with any " cleaning up " washes,
RMRDBBNJ–. Chestnut blight. Chestnut blight; Chestnut. Bui. 380, U. S. Depf. of Agriculturi Plate XV.. ENDOTHIA PARASITICA. VERTICAL SECTIONS OF STROMATA. X 49. Fig. 1 .—Showing a Young, Simple Pycnidial Cavity at the Base. Fig. 2.—In Which Neither Pycnidia Nor Perithecia Have Begun to Develop. Fig. 3.—With Irregular Chambered Pycnidia. All the above aie about the same age—four moulh.s after iuoculatiou.. 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
RMPG15NK–. Chestnut blight. Chestnut blight; Chestnut. Bui. 380, U. S. Depf. of Agriculturi Plate XV.. ENDOTHIA PARASITICA. VERTICAL SECTIONS OF STROMATA. X 49. Fig. 1 .—Showing a Young, Simple Pycnidial Cavity at the Base. Fig. 2.—In Which Neither Pycnidia Nor Perithecia Have Begun to Develop. Fig. 3.—With Irregular Chambered Pycnidia. All the above aie about the same age—four moulh.s after iuoculatiou.. 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
RMRDJ66M–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 354 FUNGOUS DISEASES OF PLANTS effuse colonies, the aerial portions of which are at first gray, be- coming darker with age. The pycnidia may sometimes be pro- duced in agar and also upon various solid media in tube cultures. Control. Preventive meas- ures have not been carefully worked out. Under ordinary circumstances orchards in good condition will suffer least. Advantage may also be de- rived from treating the limbs and trunk thoroughly with any " cleaning up " washes,
RMPG4BJK–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. HYSTEROGRAPHIUM. 233 Eostrup ^ regards it as a parasite on Fraxinus. Twigs of the ash attacked show flat collapsed plates of bark, on which are developed pycnidia containing one-celled conidia, and, later, the apothecia. On young twigs the diseased part often extends round the whole circumference, and causes the death of the upper living part. As yet I have only found this fungus as a saprophyte. HYPODERMIEAE. Hypod
RMRDBBPK–. Chestnut blight. Chestnut blight; Chestnut. ENDOTHIA GYROSA. VERTICAL SECTIONS OF STROMATA ON BEECH. X 32. FiQ. 1.—Showing Numerous Pycnidial Cavities andTwo Mature Perithecia. Fig. 2.—Showing Mature Pycnidia and Perithecia Side by Side. Except where otherwise indicate'l, the photomicrographs of strou]ata are from unytained sections cut with a freezing mlcrotouie. y. 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.. 1906-19
RMPG4CG4–. Diseases of truck crops and their control . Vegetables. Fig. 56. Egg-Plant Diseases. a. Phomopsis of leaf, 6. Phomopsis on fruit, c. cohidiophores, d, stylospores, e. pycnospores of Phomopsis vexans, f. photomicrograph of a cross section through an infected calyx of an egg plant showing pycnidia of P. vexans {c. to /. ^ter Harter), R. anthracnose on egg-plant fruit.. 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.. Taubenh
RMRDCXD9–. Manual of fruit diseases . Fruit. 258 MANUAL OF FRUIT DISEASES trunks. When affected canes are saved for bearing wood, the fungus spreads into the arm. As a rule the mycelium does not extend into the roots. Pycnidia are developed abundantly on affected canes and on green and ripening berries (Fig. 70). They appear on the former early in the spring, and may be found on canes se'erely infected the previous year or occasionally on the current year's growth. The pycnidia mature shortly after the buds burst in the spring, and the pycnospores ooze out in long, reddish yellow coils, each contain-
RMPG4BP0–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fig. 99.—Cucurbitaria Idburni. A, Stroma with pycnidia containing minute unicellular conidia. B, One of the large smooth pycnidia. (After v. Tubeuf.) The mature perithecia have a peridium consisting of a loose pseudoparenchyma with a rough warty exterior and a pore set in a distinct depression (Fig. 100.) The paraphyses are long, strong threads, often branched, and between them arise the long cylindrical asci with r
RMRDE2HJ–. Diseases of economic plants . Plant diseases. TREES AND TIMBER 433 gray border. The spots, from 3-6 mm. in diameter, often coalesce to form large blotches which are fragile, sometimes dropping from the leaf. Young leaves develop poorly and are deformed, while severe infection may cause complete defoliation of the tree.. Fig. 188.- ' Cedar apple." gall of the rust fungus. Original. Macrosporiose (Macrosporium Catalpw Ell. & Mart.).— This spot is scarcely distinguishable from phyllostictose except through the absence of pycnidia and the presence of a scant quantity of Ijlack mold. Pow
RMPG15R7–. Chestnut blight. Chestnut blight; Chestnut. ENDOTHIA GYROSA. VERTICAL SECTIONS OF STROMATA ON BEECH. X 32. FiQ. 1.—Showing Numerous Pycnidial Cavities andTwo Mature Perithecia. Fig. 2.—Showing Mature Pycnidia and Perithecia Side by Side. Except where otherwise indicate'l, the photomicrographs of strou]ata are from unytained sections cut with a freezing mlcrotouie. y. 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.. 1906-19
RMRDC1NC–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. HYSTEROGRAPHIUM. 233 Eostrup ^ regards it as a parasite on Fraxinus. Twigs of the ash attacked show flat collapsed plates of bark, on which are developed pycnidia containing one-celled conidia, and, later, the apothecia. On young twigs the diseased part often extends round the whole circumference, and causes the death of the upper living part. As yet I have only found this fungus as a saprophyte. HYPODERMIEAE. Hypod
RMPG4AWC–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. GYMNOSPORANGIUM. 397 the species already described in remaining closed at the apex, the spores escaping through trellis-like slits on the lateral walls of the peridia (Fig. 234). This fungus will not germinate on apple-trees, but on pears every leaf may be thickly covered with aecidia and pycnidia, and considerable damage to the crop thereby ensue (Fig. 233)... Pig. 231.—Longitudinal section through a conical teleut
RMRDE3FE–. Minnesota plant diseases. Plant diseases. 284 Minnesota Plant Diseases. The leaf underneath the spots is abnormally increased in size and distorted in shape. The pycnidia usually accompany the cluster cups and come from the same mycelium', but are gen- erally to be found on the upper surface of the leaf. They are probably male-cell receptacles which have lost their fertilizing- power and are now functionless. They illustrate a persistence of a habit after its usefulness has passed, a by no means uncommon phenomenon in nature.. f ^ ^ 1 Fig. 140.—Stem rust of wheat (Puccinia graminis). A secti
RMPG4EXF–. Minnesota plant diseases. Plant diseases. 284 Minnesota Plant Diseases. The leaf underneath the spots is abnormally increased in size and distorted in shape. The pycnidia usually accompany the cluster cups and come from the same mycelium', but are gen- erally to be found on the upper surface of the leaf. They are probably male-cell receptacles which have lost their fertilizing- power and are now functionless. They illustrate a persistence of a habit after its usefulness has passed, a by no means uncommon phenomenon in nature.. f ^ ^ 1 Fig. 140.—Stem rust of wheat (Puccinia graminis). A secti
RMRDFE13–. Chestnut blight. Chestnut blight; Chestnut. Endothia Canker of Chestnut SS9 They are closely crowded together, so that in cross section they appear to make up a pseudoparenchymatous tissue. These cells are more densely filled with protoplasm, and contain more pigment, than the interior cells. Pycnidia On smooth-bark, young cankers, especially in the summer, the outer cork layer is raised in numerous little blisters, with slender, yellow, waxy tendrils curling from their ruptured apices (Plate XXXVIII, Fig. i). Under each blister is a single somewhat globose pycnidiimi, surrounded by a scanty
RMPG49RW–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 466 FUNGI IMPERFECTI. stricted tissue will be found extending quite round the twig (Fig. 293). At these places the bark and cambium have been killed, whereas the higher portions of the twig have continued to increase in thickness. Numerous small black pycnidia break out on the bark of diseased places and give off small unicellular spindle-shaped conidia, which convey infection to new hosts in August or September. Ki
RMRDD7TF–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. UROMYCES. 339 of pycnidia precedes that of teleutospores. The latter have a flattened concave base and rounded apex; their episporium is marked with delicate ribs running from apex to base.. FlQ. 181.—Vromvcts Teppenanus on twigs of ALbizzia montana brought by Prof. Stahl from Java. (v. Tubeuf phot.) Fuccinia. Teleutospores two-celled, and each abjointed from its own sporophore from large distinct sori. Each cell ha
RMPG3YHM–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 256 FUNGOUS DISEASES OF PLANTS darker in color, and pycnidia, appearing as black papillae, may be produced over the entire surface. At this stage the effects of the fungus are therefore unmistakable. Later the fruit shrivels in a characteristic manner, but does not, as a rule, fall or shell. The berries on bunches thus affected may hang on the vines through- out the season. The pycnidia may also be easily observed with the unaided eye upon the dried berries. Susceptibility of varie
RMPG46ED–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 247 Conidia (=Diplodina citrullina) Pycnidia similar to the peri- thecia, spores 2-celled, hyaline, straight or curved, more or less cylindric, 10-18 x 3-5 /*. The fungus was isolated in pure culture by Grossenbacher ^"^ from muskmelons by direct transfer of diseased tissue to potato agar. Inoculations from these cultures proved the fungus capable of entering healthy uninjured tissue, the disease showing about six days after in- oculation. The brownish pycnidia origi- nate from an extensive
RMRDJF64–. Fungous diseases of plants : with chapters on physiology, culture methods and technique . Fungi in agriculture. 256 FUNGOUS DISEASES OF PLANTS darker in color, and pycnidia, appearing as black papillae, may be produced over the entire surface. At this stage the effects of the fungus are therefore unmistakable. Later the fruit shrivels in a characteristic manner, but does not, as a rule, fall or shell. The berries on bunches thus affected may hang on the vines through- out the season. The pycnidia may also be easily observed with the unaided eye upon the dried berries. Susceptibility of varie
RMPG4B5W–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. UROMYCES. 339 of pycnidia precedes that of teleutospores. The latter have a flattened concave base and rounded apex; their episporium is marked with delicate ribs running from apex to base.. FlQ. 181.—Vromvcts Teppenanus on twigs of ALbizzia montana brought by Prof. Stahl from Java. (v. Tubeuf phot.) Fuccinia. Teleutospores two-celled, and each abjointed from its own sporophore from large distinct sori. Each cell ha
RMRDCY5E–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 466 FUNGI IMPERFECTI. stricted tissue will be found extending quite round the twig (Fig. 293). At these places the bark and cambium have been killed, whereas the higher portions of the twig have continued to increase in thickness. Numerous small black pycnidia break out on the bark of diseased places and give off small unicellular spindle-shaped conidia, which convey infection to new hosts in August or September. Ki
RMPG45P9–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 533 Leptostromella Saccardo (p. 532) Pycnidia at first covered, at maturity apparently superficial, depressed convex, subcarbonous, dark colored; conidia bacillar or filiform, continuous or sep- tate. About twenty species, chiefly of no economic importance. L. elasticae E. & E. Spots large, more or less el- liptic, whitish, sordid, purplish margined; pycnidia epiphyllous, fiq. 364.—LeptostromeiTa eiastictB. hysterioid, 0.5-0.7 mm.; longi- After Stone and Smith, tudinally dehiscent; conidia ob
RMRDD70X–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. GYMNOSPORANGIUM. 397 the species already described in remaining closed at the apex, the spores escaping through trellis-like slits on the lateral walls of the peridia (Fig. 234). This fungus will not germinate on apple-trees, but on pears every leaf may be thickly covered with aecidia and pycnidia, and considerable damage to the crop thereby ensue (Fig. 233)... Pig. 231.—Longitudinal section through a conical teleut
RMPG4ATH–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 402 UREDINEAE. G. Ellisii Berk. On Chamaecyparis thyoides. The aecidial stage on Pyrus Mains and P. arhutifolia. On red cedar {Junipencs virginiana): G. macropus Lk. The aecidia and pycnidia occur on Pyrus Malus, P. coronaria, P. arhutifolia, Cratct^us tomentosa, C. Bouglasii, and Amelanchier canadensis; they are known as. Pig. 237.—Spores of Gym. hiseptaium. (After Woenile.) Fig. 23S.—Spores of Gym. Elliiii. (After
RMRDDB8Y–. The fungi which cause plant disease . Plant diseases; Fungi. 242 THE FUNGI WHICH CAUSE PLANT DISEASE oculations under all conceivable conditions, failed utterly of posi- tive results. From the Caucasus Prillieux and Delacroix "^ have described a Guignardia causing a black rot of grapes which is regarded as distinct from the usual American form, differing both in the peri- thecial and conidial stages. This is called G. baccae (Cav.) Jacz. Its conidial form Phoma reniformis eventually covers the whole berry with pustules. Two kinds of pycnidia are described. G. vaccinii Sh."^- "
RMPG3R6D–. Manual of fruit diseases . Fruit. 158 MANUAL OF FRUIT DISEASES attempt to distinguish the two die-back diseases. Where VaLsa leucostoma var. ruhesceiis is a factor, its pycnidia show as whitish dots over the surface of the lesion. (See in this connection Frost-Injury under Apple, page 35, and Die-Back under Peach, page 299.) Black-Spot Caused by Bacterium Pruni E. F. Smith As a rule, apricot fruits are less injured by black-spot than those of the other susceptible stone-fruits like the peach and plum. However, certain varieties of apricots are severely affected; the Royal, Sweet Russian, Pea
RMRDE5AE–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 509 confluent, marginally fimbriate, the radiating fibers arachnoid, white, distinctly branched; pycnidia tuberculariform, scattered or confluent, black; conidia oblong, constricted, 18-20 x 5. /i; conidiophores short. This fungus was first described in 1826. It is common on rose leaves. The mycelium is in part subcuticular, in part deeper. The subcuticular part is visible through the cuticle, consisting of radiate strands each composed of several parallel hyphae. From this mycelium branches pene
RMPG4BHA–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. LOPHODEEMIUM. 239 Lophodermium nervisequium (D. C.)^ (U.S. America). This very common fungus attacks both old and young silver firs. The needles die after becoming brown, and remain for a long 1/. Fia. 124.—lophodermium nervisequium on Abies pectinata (Silver Fir). 1, Under surface of needle with apothecia. 2, Upper surface with pycnidia. Fig. 125.—Lophodermium nervisequium. Section of a needle of Silver Fir. b, Pyc
RMRDDB7T–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 247 Conidia (=Diplodina citrullina) Pycnidia similar to the peri- thecia, spores 2-celled, hyaline, straight or curved, more or less cylindric, 10-18 x 3-5 /*. The fungus was isolated in pure culture by Grossenbacher ^"^ from muskmelons by direct transfer of diseased tissue to potato agar. Inoculations from these cultures proved the fungus capable of entering healthy uninjured tissue, the disease showing about six days after in- oculation. The brownish pycnidia origi- nate from an extensive
RMPG0GAX–. Diseases of greenhouse crops and their control . Vegetables; Plant diseases; Plant diseases. Fig. 46. Carnation Diseasbs. a. White tip (after Clinton), b-f. carnation rust parasite (after Blodgett, F. H.), g. stigmanose (after Woods), h. Septoria leaf spot (after Potter, M. C), »• pycnidia of Septoria dianthi, j. pow- dery mildew fungus (after Mercer, W. B.).. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Taubenhaus, Ja
RMRDE0BR–. Diseases of truck crops and their control . Vegetables. Fig. 56. Egg-Plant Diseases. a. Phomopsis of leaf, 6. Phomopsis on fruit, c. cohidiophores, d, stylospores, e. pycnospores of Phomopsis vexans, f. photomicrograph of a cross section through an infected calyx of an egg plant showing pycnidia of P. vexans {c. to /. ^ter Harter), R. anthracnose on egg-plant fruit.. 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.. Taubenh
RMPG0RBD–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 495 hyphffi, rostrum, 20-30 fi long, apically fimbriate; conidia globose- elliptic, 5-9 II. The fungus grows in the sweet potato producing dark, almost black spots in the skin. The tissue below becomes olive-green. The dark mycelium is found penetrating through and between cells of the dis- eased area where numerous olivaceous conidia are also present. The elon- gated beaks of the pycnidia rise like a small forest from the surface of the potato. In artificial culture the mycelium is dark, abundan
RMRPY17J–. Hawaiian Fungi. Fungi. 130 Bernice P. Bishop Museum—Bulletin On Colo casta sp. (taro). Hawaii: Keauhou, Kona, Bishop Estate road, July 23, no. 943; Kilauea, July 16, no. 873. This fungus appears to be of wide distribution on the islands, and its ravages cause such havoc that the leaves are largely or quite destroyed. Since the taro plant is of such high food value in the Hawaiian islands, this disease is of special interest, and it may prove to be of serious economic importance.. Figure28.—Pycnidia and spores: a, of Phyllosticta colocasiophila—section showing pycnidia; b, of Harknessia gunne
RMPG4AXX–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 390 UREDINEAE. In May or June the cushions swell up and become large brownish-yellow gelatinous clumps, dotted over with dark points, the teleutospores. Promycelia arise from one or more germ- pores in each spore, and give off basidia with sporidia (basidio-. FiG. 224.—Aecidia and Pycnidia of various species of Gyninosporangium : G. tremetloides—1 and S, aecidia on leaf of Pyrvs Ai-ia ; 5 and 6, aecidia on leaf of P
RMRDWC2W–. The essentials of botany. Botany. IMPERFECT FUNGI 239 producing whitish or discolored spots, and eventually developing small perithecia-like structures (pycnidia) containing conidia. Species of Phyllosticta are common on leaves of Virginia creeper, wild grape, cottonwood, willow, pansy, peach, apple, wild cherry, elm, etc., while species of Septoria are to be found on leaves of box-elder, aster, thistle, evening primrose, wild lettuce, plum, elder, etc. 412. The Black-dot Fungi (Order Melanconiales) differ from the preceding mainly in the absence of a distinct perithecium, the spores develop
RMPG4BPB–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 208 ASCOMYCETES. will be found changing from vellow to black on account of the periderm and dead stroma becoming darker. On dead branches the large cushions of fructifications will be found to include: {a) perithecia with a warty exterior and pores set in a depression; (&) large pycnidia, standing out from the cushions, with brown smooth coats, and full of compound multiseptate conidia (Fig. 9 9, B; see below No
RMRDE5CT–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 495 hyphffi, rostrum, 20-30 fi long, apically fimbriate; conidia globose- elliptic, 5-9 II. The fungus grows in the sweet potato producing dark, almost black spots in the skin. The tissue below becomes olive-green. The dark mycelium is found penetrating through and between cells of the dis- eased area where numerous olivaceous conidia are also present. The elon- gated beaks of the pycnidia rise like a small forest from the surface of the potato. In artificial culture the mycelium is dark, abundan
RMPG4F89–. Diseases of economic plants . Plant diseases. APPLE DISEASES OF SPECIAL CROPS PoMACEOus Fruits Bitter rot, ripe rot {Glomerella rufomaculans (Berk.) Spaul. & von Schrenk). Untrue to its. two common names, this malady does not always render apples bitter, though. Fig. 21.âApple bitter rot (glomerellose) in early stage showing pycnidia. After Scott. this is sometimes the case; nor is the disease always lim- ited to ripe fruit. Its effect is seen upon both the fruit and the twig. Upon the fruit it produces a soft, wet, or in later stages corky, more or â less dry, brown, tan-colored, or bla
RMRDED2M–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 390 UREDINEAE. In May or June the cushions swell up and become large brownish-yellow gelatinous clumps, dotted over with dark points, the teleutospores. Promycelia arise from one or more germ- pores in each spore, and give off basidia with sporidia (basidio-. FiG. 224.—Aecidia and Pycnidia of various species of Gyninosporangium : G. tremetloides—1 and S, aecidia on leaf of Pyrvs Ai-ia ; 5 and 6, aecidia on leaf of P
RMPG0RBR–. The fungi which cause plant disease . Plant diseases; Fungi. 492 THE FUNGI WHICH CAUSE PLANT DISEASE P. apiicola Speg. is recorded on celery.'^ P. brassicse Thiim. on cabbage is probably identical with P. oleraceae. P. roumii Fr'on. is said to cause a serious cotton disease in Africa.*' P. batatSB E. & H.*^ Pycnidia blackish, gregarious, immersed; conidia terete, ovoid; conidiophores slender. The cause of dry rot of sweet pota- toes. P. chrysanthemi Vogl. is found on leaves of chrysanthemum causing them to wilt. P. malvacearum West is noted on European hollyhocks; P. devastatriz Berk, on
RMRDED17–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 402 UREDINEAE. G. Ellisii Berk. On Chamaecyparis thyoides. The aecidial stage on Pyrus Mains and P. arhutifolia. On red cedar {Junipencs virginiana): G. macropus Lk. The aecidia and pycnidia occur on Pyrus Malus, P. coronaria, P. arhutifolia, Cratct^us tomentosa, C. Bouglasii, and Amelanchier canadensis; they are known as. Pig. 237.—Spores of Gym. hiseptaium. (After Woenile.) Fig. 23S.—Spores of Gym. Elliiii. (After
RMPG46A6–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 275 =Fuscicoccum veronense). Pycnidia formed on old leaves on the ground, erumpent, subcuticular, brown, 200-300 /i; conidia numerous, oblong, ovoid to fusoid, 7-11 x 3-i n. The conidial form on sycamore and oak, first described in 1848, is common on leaves and young branches, the mycelium checking the sap-flow and causing death of surround- ing tissue. A stroma is formed on the outer layers of the mesophyll and from this arise the short conidiophores to constitute the acervulus. Infection experi
RMRDCXNR–. Manual of fruit diseases . Fruit. 158 MANUAL OF FRUIT DISEASES attempt to distinguish the two die-back diseases. Where VaLsa leucostoma var. ruhesceiis is a factor, its pycnidia show as whitish dots over the surface of the lesion. (See in this connection Frost-Injury under Apple, page 35, and Die-Back under Peach, page 299.) Black-Spot Caused by Bacterium Pruni E. F. Smith As a rule, apricot fruits are less injured by black-spot than those of the other susceptible stone-fruits like the peach and plum. However, certain varieties of apricots are severely affected; the Royal, Sweet Russian, Pea
RMPG4GAN–. The fungi which cause plant disease . Plant diseases; Fungi. 208 THE FUNGI WHICH CAUSE PLANT DISEASE P. ruba (Pers.) D. C. causes reddish spots on the leaves of Prunus. Stroma at first bearing pycnidia (Libertella rubra) with filiform hooked, con- tinuous conidia. Perithecia produced on old leaves, bearing ellipsoid to elongate asci; spores 10-13 x 6 m, smooth. The invaded leaf'tissue is colored by the mycelium which bears a reddish oil. Nu- merous perithecia are immersed in the diseased area and, opening to the surface, extrude spores which seem incapable of in- fecting. During winter the s
RMRDE589–. The fungi which cause plant disease . Plant diseases; Fungi. THE FUNGI WHICH CAUSE PLANT DISEASE 533 Leptostromella Saccardo (p. 532) Pycnidia at first covered, at maturity apparently superficial, depressed convex, subcarbonous, dark colored; conidia bacillar or filiform, continuous or sep- tate. About twenty species, chiefly of no economic importance. L. elasticae E. & E. Spots large, more or less el- liptic, whitish, sordid, purplish margined; pycnidia epiphyllous, fiq. 364.—LeptostromeiTa eiastictB. hysterioid, 0.5-0.7 mm.; longi- After Stone and Smith, tudinally dehiscent; conidia ob
RMPG15RB–. Chestnut blight. Chestnut blight; Chestnut. Plate X.. Fig. 1.—Endothia fluens. Vertical Section of a Stroma from Italy, Showing Young Perithecia IN A Single Layer. X 49. Fig. 2.—Endothia qyrosa. Ver- tical Section of a Stroma on Beech, Showing Mature Pycnidia with Mature Perithecia below Them, x 32. FiQ. 3.—Endothia qyrosa. Vertical Section of a Portion of a Large Stroma, Showing Perithecia Irregularly Arranged IN Several Layers.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these ill
RMRDC1KN–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. LOPHODEEMIUM. 239 Lophodermium nervisequium (D. C.)^ (U.S. America). This very common fungus attacks both old and young silver firs. The needles die after becoming brown, and remain for a long 1/. Fia. 124.—lophodermium nervisequium on Abies pectinata (Silver Fir). 1, Under surface of needle with apothecia. 2, Upper surface with pycnidia. Fig. 125.—Lophodermium nervisequium. Section of a needle of Silver Fir. b, Pyc
RMPG4DMH–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 624 LABORATORY EXERCISES LESSON 22 Isolation oj a Leaf Will Fungus in Pure Culture—Givea a fungus causing leaf wilt, to obtain a pure culture by excluding the non-pathogenic forms. I. Look for the fruiting stage of the suspected fungus, or fungi. Transfer some of the spores with a sterile needle into a tube of s c.c. of sterile water. (If pycnidia or perithecia are present, transfer a whole pycnidium or perithecium into sterile water, and crush the fruit body to cause the escape of the
RMRDC1Y7–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. 208 ASCOMYCETES. will be found changing from vellow to black on account of the periderm and dead stroma becoming darker. On dead branches the large cushions of fructifications will be found to include: {a) perithecia with a warty exterior and pores set in a depression; (&) large pycnidia, standing out from the cushions, with brown smooth coats, and full of compound multiseptate conidia (Fig. 9 9, B; see below No
RMPG4CPY–. Diseases of truck crops and their control . Vegetables. Fig. 26. Sweet Potato Diseases. a. Black rot at place of a bruise, b. black shank, c. showing a pycnidium of the black rot fungus, d.- dry rot, e. cross section through /, to show the effect of the disease on the root, /. Java black rot surface view, showing strings of spores oozing out from the center of spot, g. cross section through diseased sweet potato root to show pycnidia of the fungus Diplodia tubericola.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability -
RMRDETGW–. A text-book of mycology and plant pathology . Plant diseases; Fungi in agriculture; Plant diseases; Fungi. 624 LABORATORY EXERCISES LESSON 22 Isolation oj a Leaf Will Fungus in Pure Culture—Givea a fungus causing leaf wilt, to obtain a pure culture by excluding the non-pathogenic forms. I. Look for the fruiting stage of the suspected fungus, or fungi. Transfer some of the spores with a sterile needle into a tube of s c.c. of sterile water. (If pycnidia or perithecia are present, transfer a whole pycnidium or perithecium into sterile water, and crush the fruit body to cause the escape of the
RMPG4BH0–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fia. 124.—lophodermium nervisequium on Abies pectinata (Silver Fir). 1, Under surface of needle with apothecia. 2, Upper surface with pycnidia. Fig. 125.—Lophodermium nervisequium. Section of a needle of Silver Fir. b, Pycnidium on upper surface shedding conidia. a, Apothe- cium on the lower surface. (After R. Hartig.). Fig. 126.—lophoderviium nervisequium on Silver Fir. Portion of a ripe apothe- cium. a a, Filament
RMRDC1KA–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. Fia. 124.—lophodermium nervisequium on Abies pectinata (Silver Fir). 1, Under surface of needle with apothecia. 2, Upper surface with pycnidia. Fig. 125.—Lophodermium nervisequium. Section of a needle of Silver Fir. b, Pycnidium on upper surface shedding conidia. a, Apothe- cium on the lower surface. (After R. Hartig.). Fig. 126.—lophoderviium nervisequium on Silver Fir. Portion of a ripe apothe- cium. a a, Filament
Download Confirmation
Please complete the form below. The information provided will be included in your download confirmation