大豆灰斑病抗感标准划分的研究

STUDY ON RESISTANCE STANDARD OF SOYBEAN PLANTS TO CERCOSPORA SOJINA Hara

大豆灰斑病抗感鉴定标准的确立一直是抗病育种及抗病机理研究中的关键问题 ,也是一个难点。本文以大豆杂交组合的后代为材料 ,从各组合F2 植株的病情分布、F3株系的抗感分离以及植株抗重复再侵染能力的角度 ,对大豆抗灰斑病的抗感鉴定标准进行研究。提出 :在用混合菌种对大豆材料进行田间接种的条件下 ,大豆灰斑病的抗感鉴定标准应定在病斑型级数为B2 处 ,即植株叶片的病斑数量不能超过 5 -

The establishment of resistance standard of soybean plant is very important but difficult to distinguish in resistance breeding and mechanism studies. The spots distributions of F 2 plant, the resistant-sensitive rate of the separations in F 3 lines of different F 2 plants and the resistance ability after the first invasion of Cerospora sojina Hara in soybean plant was discussed in the paper. The resistant-sensitive standard of soybean plant to Cerospora sojina Hara with several physical races existed should be at the point that BBXJS is 10. This means that the spots of the resistant plants in this system should be less than 5-8 spots.