. Journal of the Department of Agriculture, Union of South Africa. Fui. 2. and No. Ill those whicli had formed normal ears, and on which noindications oT the disease were visible. The actual numbers ofdiseased and of healthy stools in the product of this square yard wascounted, and was as follows : — Healthy stools 33 Ears produced by the above 85 Diseased stools 20 Partially diseased stools T Healthy ears produced by the above 9 Diseased stalks 10 Thus the actual percentage of stools showing disease, as comparedio llie number of healthy stools in this field, would be 45 per 254 Journa
. Journal of the Department of Agriculture, Union of South Africa. Fui. 2. and No. Ill those whicli had formed normal ears, and on which noindications oT the disease were visible. The actual numbers ofdiseased and of healthy stools in the product of this square yard wascounted, and was as follows : — Healthy stools 33 Ears produced by the above 85 Diseased stools 20 Partially diseased stools T Healthy ears produced by the above 9 Diseased stalks 10 Thus the actual percentage of stools showing disease, as comparedio llie number of healthy stools in this field, would be 45 per 254 Journal of the Department of Agriculture. General Characters and Symptoms. The disease first becomes visible to the naked eye as black streakson the leaves, parallel with the veins, and extending along- the lengthof the leaf blade. (See Fig. 2, which is an enlarged drawino- of aportion of a leaf.) ^ The whole plant is stunted, and the leaves frequently becomemuch twisted and distorted. The whole stool may be diseased, in. Fig 3. which case it is killed outright, or else only some of the shoots of thestool, the rest forming normal ears, though undersized ones. Thegeneral appearance of a typically diseased wheat plant reminds oneot a comnion cattle tulp plant, and it is from this similarity in appear-ance which has given rise to the South African name of fulp brand i ^^^^^lisease (Fig. 3). Fig. 4 is a photogi-aph taken in a wheat-fieldwhere the disease is prevalent, and shows in the foreground a normalstool on the right, and a diseased one on the left; the latter is less than FLA(i Smut of Wheat 255 half the height of the former, and has made no evident attempt toform ears. As a riile the plant is attacked so severely that it is unableto produce even young ears; sometimes a diseased stalk does form anear with grain, but usually the ear is attacked while still very youngand enclosed in its leaf sheath. Cause of Disease. Flag smut of wheat is caused by a fungus, Urocystis fritisi,Koern
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