【摘要】 用散布性重复序列MGR586 探针与EcoRI组合,分析广东省稻区的112 个稻瘟病菌株( M. grisea )的限制性片段长度多态性(RFLPs),根据带型相似性大于80% 为度划分为15个遗传宗谱(genetic lineage)。这些在分子水平上划分的宗谱与寄主品种的遗传背景关系密切。由于广东省(包括华南稻区)大多数育成的常规稻品种和杂交稻组合在遗传背景上与GDL1 及GDL2 两个优势病菌宗谱寄主具有相似的共进化同缘宗亲关系, 致使品种的抗性水平不高,抗性周期短暂。从而提出了选择异源供体, 开展多元化育种的方向及途径。更多还原

【Abstract】 Fifteen genetic lineages of the rice blast pathogen(M. grisea)were clustered based on their band paterns in the RFLPs haplotype measured by the RFLP among 112 pathogen collected from four rice ecological growth regions in Guangdong province. The diversity of blast pathogens in DNA fingerprinting were closely related with the host genetic background of the host based on their affinity and adaptability in V×I interaction to blast. Experimental results disclosed the phenomina of short life cycle of blast resistance in most of conventional rice cultivars and hybrid rice cultivars developed by Guangdong even though in South China were in short of durable resistant sources. Furthermore, the way for improvement of breeding program in blast disease resistance was also discussed and suggested.更多还原