Fungi, Ascomycetes, Ustilaginales, Uredinales . ts in which yellowish whitestromata are produced. These give rise to minute unicellular conidia, andlater, if the atmosphere is sufficiently moist, to ascocarps. In the genus Sclerotinia the stalked ascocarps arise from sclerotia (fig. 81 i number of species arc parasitic : S. tuberosa on - Xnemone nodosa; S. sclero-tiorum on the potato, cabbage and other hosts in the stems of which thesclerotia are formed; and .V. entered on species ofPrunus andPyrus where they give rise to brown rot, blossom wilt and other pathologicalcondition
Fungi, Ascomycetes, Ustilaginales, Uredinales . ts in which yellowish whitestromata are produced. These give rise to minute unicellular conidia, andlater, if the atmosphere is sufficiently moist, to ascocarps. In the genus Sclerotinia the stalked ascocarps arise from sclerotia (fig. 81 i number of species arc parasitic : S. tuberosa on - Xnemone nodosa; S. sclero-tiorum on the potato, cabbage and other hosts in the stems of which thesclerotia are formed; and .V. entered on species ofPrunus andPyrus where they give rise to brown rot, blossom wilt and other pathologicalconditions; ,s. bulborum on hyacinth and other bulbs, and various species on I24 DISCOMYCETES [CH. members of the Vaccinieae, where the sclerotia are formed on the 5. Vaccitiii the conidia are produced in chains and are separated by smallcellulose disjunctors. They have a characteristic smell of almonds andare carried to the flower by insects, and probably also by wind ; theygerminate to form septate hyphae which enter and fill the ovary. The. Fig. 86. Sclerotinia tuberosa (Hedw.) Fuck.; sclerotia and apothecia, nat. size. mummified berries fall prematurely, lie during winter on the earth, and inspring give rise to the goblet shaped apothecia. In other species the conidiaare borne on a conidiophore and belong to the form-genus Botrytis; theconidial phase on Primus and Pyrus is known as Monilia. The ascosporesare unicellular and hyaline and often of unequal size. Celidiaceae, Patellariaccac, and Cenangiaceae In the previously described families the consistency of the ascocarp iseither fleshy or waxy. In the following three, Celidiaceae, Patellariaceae,and Cenangiaceae, it is leathery, horny, or cartilaginous, and the ends of theparaphyses are interwoven to form a layer above the asci known as theepithecium. The hypothecium is well developed, the ascospores are some-times more than eight in number and are one to many-celled; in somespecies pycnidia are present. The three familie
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectfungi, bookyear1922
