Abstract:

Medium and late rice were affected by rice black streaked dwarf virus in varying degrees in Chenxi County in 2009.Incidence area was of 3,666.67 ha. Incidence rate of medium rice was at 17.96% and that of late rice at 21.18%. Yield loss was generally at 10% -20%, severely at 70 % or even no gain. Quantities of white-backed planthopper were much bigger than brown planthopper in the field. There were two occurrence peaks in late June and late July respectively. As white-backed planthopper is an importance of the media of rice black-streaked dwarf virus, it leads in a large area of this disease. In different rice varieties, Zhong you 288, T You 272, Ⅱ 117, Yi S wan no.2, Hua Liang you 4480, etc. were easily susceptible and the incidence rate of them above 50%, whereas that of Yue you 9113 at ≤ 5%, and more resistant.