水稻抗条纹叶枯病育种实践与策略

[目的]培育优质、高抗条纹叶枯病的水稻品种。[方法]将镇稻88、镇稻99、徐稻3号和武运粳7号、武粳14进行杂交和回、复交,田间自然接虫,鉴定亲本及后代的抗性。[结果]镇稻88、镇稻99、徐稻3号条纹叶枯病田间发病率只有5%左右,抗源均来自一对不完全显性基因Stv-bi;2007年武运粳7号、武粳14年发病率高达40%以上。抗条材料作父本或母本,后代中选到抗条植株的概率达40%;2个抗条材料杂交,后代中选到抗条植株的概率达70%以上。回、复交时抗条材料占50%,后代选到抗条材料的概率占40%,高抗株占15%左右;抗条材料占75%时,后代选到抗条材料的概率占50%,高抗株占20%左右。[结论]加强对现有水稻资源的抗性筛选,研究新的抗病基因(或位点)的遗传规律,有助于培育抗条纹叶枯病的水稻品种。

Breeding Practice and Strategy of Rice Resistant to Stripe Disease

[Objective] The aim of the study was to breed rice variety with good quality and high resistance to stripe disease.[Method] Zhendao 88,Zhendao 99, Xudao 3,Wuyungeng 7 and Wuyungeng 14 were crossed,backcrossed and multiple crossed,inoculated with pests naturally in field and the resistances of parents and offspring were identified.[Result] The bacterial bearing rates of stripe disease on Zhendao 88,Zhendao 99 and Xudao 3 in field was only about 5% and all the resistance sources came from a pair of incompletely dominant genes Stv-bi.The bacterial bearing rates of Wuyungeng 7 and Wuyungeng 14 reached higher than 40% in 2007.With materials resistant to stripe disease as male parent or female parent,the possibility of choosing out the plants with resistance to stripe disease among offspring reached 40%.When 2 materials with resistance to stripe disease were crossed,the possibility of choosing out the plants with resistance to stripe disease among offspring was higher than 70%.The materials with resistance to stripe disease accounted for 50% in backcross and multiple cross,the possibility of choosing out the materials with resistance to stripe disease among offspring accounted for 40% and the plants with high resistance accounted for about 15%.When the materials with resistance to stripe disease accounted for 75%,the possibility of choosing out the materials with resistance to stripe disease among offspring accounted for 50% and the plants with high resistance accounted for about 20%.[Conclusion] Strengthening resistance screening of rice resources at present and studying the heredity law of new resistance genes(or sites) were helpful for breeding rice variety with resistance to stripe disease.