论文部分内容阅读
对1982年宁夏引黄灌区银川、灵武、吴忠、青铜峡、中宁、中卫等县(市)的病稻草上稻瘟病菌越冬存活率及越冬稻瘟病菌的生活力进行了测定。其结果稻瘟病菌越冬存活率为13.34—66.67%;越冬稻瘟病菌生活力较强,所产生的分生孢子的发芽率为33.33—100%,其中绝大多数在80%以上。初步证明,宁夏引黄灌区病稻草上所带的稻瘟病菌在冬季严寒的环境条件下能顺利越冬,越冬后所产生的分生孢子萌发率较高。 1983年,用本区分布范围广、出现频率高的毒性小种ZE_1Nb_1的同一单孢后代对宁夏引黄灌区主要水稻栽培品种,进行了苗期(四叶期)孢子悬浮液喷雾接种试验。结果不同品种间病情增长率差异显著;病情增长总值差异极显著;处理间差异不显著。初步证明,同一毒性小种对不同品种的侵袭力有显著差异。由此看出,在新的毒性小种的出现和增殖而丧失垂直抗病性的情况下,我区主要水稻栽培品种间对稻瘟病水平抗性的程度仍有明显的差别。
The survival rates of overwintering and the viability of Magnaporthe grisea on the rice in Yinchuan, Lingwu, Wuzhong, Qingtongxia, Zhongning and Zhongwei counties of Ningxia Yellow River Irrigation Area in 1982 were measured. As a result, the overwintering survival rate of Magnaporthe grisea was 13.34-66.67%, and the viability of Magnaporthe grisea was strong. The germination rate of conidia produced was 33.33-100%, most of them were over 80%. It was initially proved that M. grisea on the diseased straw in Ningxia Yellow River Irrigation Area could successfully winter in winter under the severe cold conditions, and germination rate of conidia was higher after overwintering. In 1983, the same single spore generation of ZE_1Nb_1 was used to inoculate the main rice cultivars in Ningxia Yellow River Irrigation Area at the seedling (four-leaf stage) spore suspension inoculation. Results There were significant differences in disease growth rate among different varieties; the total value of disease growth was extremely significant; the difference between treatments was not significant. Preliminary evidence that the same toxic races on the invasiveness of different varieties have significant differences. This shows that in the emergence and proliferation of new toxic races and the loss of vertical resistance in the case, the main rice cultivars in our region to the degree of blast resistance levels are still significantly different.