摘要
高水平抗纹枯病突变体Rsb发现于高感纹枯病的籼粳杂交组合(蜀恢955×Kitaake)的BC2F2。为了考查Rsb在不同条件下的抗性,经花药培养得到的Rsb纯系的抗性研究从以下2个方面进行:一是接种不同的国际标准菌株、常规栽培条件,二是以四川水稻高产栽培的N肥用量为最低水平,在接种强致病性纹枯病菌的情况下,高N肥和不同栽插密度。结果表明,在常规栽培条件下Rsb仍然具有高水平抗性;AG1-IA的致病力最强。但是,在高N肥条件下其抗性要发生变化,不再表现高水平抗性,从Rush病级指数看,仅为中间类型,只表现出对纹枯病的忍耐力。本田栽插密度对Rsb纹枯病的发病影响相对较小。相关分析表明,水稻纹枯病发病病级与施N量呈极显著相关,其相关系数r=0.867 3**。说明Rsb存在真实遗传的纹枯病抗性,其抗性为主效基因所控制。同一水稻品种对纹枯病的抗性反应主要受N肥施用量的影响。
Rsb,mutant with high level resistance to sheath blight was found in BC2F2 of indica x japonica （Shuhui 955 × Kitaake）, which were much susceptible to sheath blight of rice. Resistant analysis of the pure Rsb, which was gotten by anther culture, was carried out in two manners. Firstly, it was done in general cultivation by using different international standard strains;Secondly, it was done in much quantity application of N and different transplanting density by using isolate with high pathogenicity, in which the application of N of high -yielding practices in Sichuan was designed as the lowest level Results indicated that Rsb still had high level resistance to sheath blight under general cultivation and pathogenicity of AG 1-IA was the highest for all international standard strains tested. However, it did not show high level resistance to sheath blight and was middle type in Rush disease rating, only having endurance when it was transplanted in much quantity application of N and different transplanting density. The effect of transplanting density to infection of sheath blight was smaller than that of application of N. Analysis on correlation indicated that the disease rating of sheath blight had significant correlation with application of N at 1% level（r =0. 867 3 ^＊ ＊ , Fig. 1 ）. The resistance of Rsb is heritable and true, and it is controlled by major genes. The resistance response of same rice cultivar to sheath blight is mainly affected by the application quantity of N.
出处
《种子》
CSCD
北大核心
2008年第9期1-5,共5页
Seed
基金
国家“八六三”计划项目(2006AA10Z1D1)
西南科技大学博士基金项目(07zx0101)
四川省教育厅重点项目(07ZA130)
