. Fungous diseases of plants, with chapters on physiology, culture methods and technique . Fig. 71. Section of Peach Twig affectedWITH THE MoNiLiA. (After Er\v. F. Smith) 192 FUNGOUS DISEASES OF PLANTS On blighted branches of the peach the myceUum has beenfound (Smith) to grow most abundantly in the cambium and softbast, these tissues disappearing in large measure with the forma-tion of extensive gum pockets (Fig. 71). The conidiophores arise as short hyphae, which soon becomeseptate at the extremities, branched and nodulose. The branchingproceeds in an indefinite and usually irregular or semi
. Fungous diseases of plants, with chapters on physiology, culture methods and technique . Fig. 71. Section of Peach Twig affectedWITH THE MoNiLiA. (After Er\v. F. Smith) 192 FUNGOUS DISEASES OF PLANTS On blighted branches of the peach the myceUum has beenfound (Smith) to grow most abundantly in the cambium and softbast, these tissues disappearing in large measure with the forma-tion of extensive gum pockets (Fig. 71). The conidiophores arise as short hyphae, which soon becomeseptate at the extremities, branched and nodulose. The branchingproceeds in an indefinite and usually irregular or semidichotomousfashion (Fig. 72, a and b). From the apex of these branchestoward the base conidia are rapidly cut off, these cells remainingfor a time simply moniliform or as branched chains, each con-striction between the nodulations eventually marking the line of. Fig. 72. SCLEROTINIA FRUCTIGENA : CONIDIOPHORES AND CONIDIA, Section of Apothecium, Ascus, and Ascospores separation between adjacent spores. The spores germinate readily,and often while still massed in the tuft of conidiophores, that is,before being blown or brushed away. Germination studies haveshown that many of the conidia may live through until the suc-ceeding season, and, as indicated, the mycelium is even morecapable of effective hibernation. Ordinarily no apothecial stage has been observed to interveneregularly in the life cycle of this fungus, and the ascosporous orSclerotinia stage is not believed to be important to continue thepropagation of the fungus. During the spring of 1902 the Scle-rotinia stage was found (Norton) quite commonly in the orchards^.pi Maryland. The apothecia were discovered arising from scle-rotia, which might be developed either within the tissues or on ASCOMYCETES 193 the surface of the mummied fruits. The fruits upon which thisstage appeared had been
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