Report by College of Agriculture and Forestry In "Agriculture &. Forestry Notes" issued by the College of Agriculture & Forestry of the Uniity of Nanking, the following details are given of crop diseases in the country adjacent to Nanking:—Itis taken as a generally acco} fact that crop diseases in China are very prevalent. Last spring Mr. R. H. Porter, plant. pathologist in the department of biology, carried on a number of field surveys about Nanking, and made the following varioi Among the imestimates of damage caused by
portant diseases about Nanking it was found that flag smut of wheat was common in practically every farmer's field, reducing the yield from 6 to 80 per cent. An average of 15 per cent. loss is fairly representative of the whole. In addition to smut, all wheat was infected with leaf rust.. This first appeared about April 15 but'as the warm, moist weather came on, this rust spread very rapidly, killing the lower leaves and reducing the vitality of the plants, A conservative estimate of the loss caused by this rust alone is 8 per cent, About 10 days before the wheat ripened the black stem rust appeared and caused a slight loss. Following is a brief list, by no means complete, of other plant diseases observed this year around Nanking and an estimate of the loss caused by these diseases.
Other diseases of wheat: loose smut, 2 per cent.; powdery mildew, 5 per cent. Burley diseases: covered smut, 5 per cent.; loose smut, 5 per cent; powdery mildew, trace; stripe disease, -per cent. Broad beans; rust 4 per cent. leat spot, 8 per cents Rape: downy mildew, 4 per cent, peach: brown rot, 4 per cent, Peat cedar rust, leaves killed, 75 per cent, infection, yield reduction possibly 15 per cent. -In addition to the diseases caused by fungi, plant lice were very. [prevalent on.many crops,
Text read from the printed page and cleaned; old type leaves the occasional error.