1911 Encyclopædia Britannica/Botrytis

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BOTRYTIS, a minute fungus which appears as a brownish-grey mould on decaying vegetation or on damaged fruits. Under a hand-lens it is seen to consist of tiny, upright, brown stalks which are branched at the tips, each branchlet being crowned with a naked head of pale-coloured spores. It is a very common fungus, growing everywhere in the open or in greenhouses, and can be found at almost any season. It has also a bad record as a plant disease. If it once gains entrance into one of the higher plants, it spreads rapidly, killing the tissues and reducing them to a rotten condition. Seedling pines, lilies and many other cultivated plants are subject to attack by Botrytis. Some of the species exist in two other growth-forms, so different in appearance from the Botrytis that they have been regarded as distinct plants: — a sclerotium, which is a hard compact mass of fungal filaments, or mycelium, that can retain its vitality for a considerable time in a resting condition; and a stalked Peziza, or cup-fungus, which grows out of the sclerotium. The latter is the perfect form of fruit. The Botrytis mould is known as the conidial form