水稻圆斑病研究

STUDIES OF RICE CIRCULAR SPOT DISEASE (NIGROSPORA ORYZAE BETCH)

1983年从湖南醴陵县水稻品种浙辐802和威优35叶片上发现的圆形病斑,经研究证实为Nigrospora oryzae(Ber. and Br.)Fertch引起的。本文对该病的症状作了描述,对病菌的某些生理性状作了研究,并将在水稻和稗上分离的病菌交互接种。结果可以相互感染。病害发生规律观察表明,病害发展受水稻生育期制约,齐穗期后病情急剧加重。目前推广的品种间发病无显著差异,不同氮、磷、钾施肥水平对病害发生影响不大。从孕穗末期开始先后喷药两次。供试药剂稻瘟净(0.5%),克瘟散、富士一号、三环唑、托布津、山苍子油(均为0.1%)和50ppm井岗霉素,均无显著防效。

Circular spots were found on the leaves of some rice varieties of Zhefu 802, Weiyou 35 etc. in Liling county, Hunan in 1983. The pathogen of the disease has been identified as Nigrospora oryzae (Ber. & Br.)Betch. The symptom of the disease and some physiological characters of the pathogen are described. Pathogens isolated from infected rice and barnyard grass (Echinochloa crusgalli)infect each other's host after inoculation. The occurrance of the diseases in paddies was regulated by the growth and development phase of rice. The severity of the disease sharply increased after full heading stage. The incidence of the disease did not show significant difference in the 7 varieties tested or to the levels of N. P. K. ertilization. At the late booting phase, chemicals were sprayed twice at 10-day interval. The use of 0.5% Kitazin P. 0.1% Hinosan, Fujione, Tricyclezol, Thiophanote methyl, cubeb litsea oil and 50ppm Jinggongmycin showed no obvious effect.