. Diseases of crop-plants in the Lesser Antilles. Tropical plants; Plant diseases. 322 DISEASES OF CROP-PLANTS The affection begins on young leaves and develops thickly sown irregular spots, bright yellow on the upper surface of the leaf, covered on the under side in moist weather with a dirty- white web of hyphae. Later the spots show red dots or stripes, and in individual instances may become dull red. On the under surface bundles of short conidiophores project from the stomata and bear elongated hyaline conidia of varying length and with i-6 cells. Brown Leaf-Spot. Brown leaf-spot is record
. Diseases of crop-plants in the Lesser Antilles. Tropical plants; Plant diseases. 322 DISEASES OF CROP-PLANTS The affection begins on young leaves and develops thickly sown irregular spots, bright yellow on the upper surface of the leaf, covered on the under side in moist weather with a dirty- white web of hyphae. Later the spots show red dots or stripes, and in individual instances may become dull red. On the under surface bundles of short conidiophores project from the stomata and bear elongated hyaline conidia of varying length and with i-6 cells. Brown Leaf-Spot. Brown leaf-spot is recorded by Gough in Trinidad and as one of the rarer leaf-spots in Porto Rico by Johnston and Fig. 136 Cercospora Longipes From Memoirs, Dept. Agri., India It is reported to be by far the commonest leaf disease on the thin canes of India, to which it is practically confined. The spots appear on the blade of the immature leaf and continue during maturity. At first they are narrow, oval, about ^ inch in length, and reddish in colour. A browTi centre early becomes evident, and a yellow border is formed, so that the spot is tri- coloured. When fully developed the spots consist of a broad oval deep-brown ring, with a straw-coloured centre, the whole reaching to half an inch in length. The causative fungus is Cercospora longipes, Butler. Long brown unbranched conidiophores, abruptly bent, form a velvety. 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 Nowell, William, 1880-; West Indies (British). Imperial Dept. of Agriculture. London, West India Committee
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectplantdi, bookyear1923
