5个水稻品种对美国稻瘟病小种(IB-1,IE-1k,IG-1)的抗性遗传(英文)

为研究5个水稻品种对美国稻瘟病小种IB-1、IE-1k和IG-1的抗性遗传,于2008―2009年在美国阿肯色大学潘布拉夫分校和水稻研究推广中心,用中国水稻品种特青和4个美国水稻品种Katy、Mars、LaGrue和Newbonnet组成完全双列杂交。一代、杂交二代和亲本在温室,用美国稻瘟病(Magnaporthegrisea)3个主要菌原小种IB-1、IE-1k和IG-1进行接种鉴定,进行完全双列杂交遗传分析研究。结果表明:特青抗所有的小种;Katy抗IB-1和IG-1,但感IE-1k;Mars抗IE-1k和IG-1,但感IB-1;LaGrue感所有小种;Newbonnet抗IG-1,但感IB-1和IE-1k。抗病品种特青与感病品种Newbonnet对小种IB-1,抗病品种特青与抗病品种Mars对IE-1k,抗病品种特青与抗病品种Katy,抗病品种特青与抗病品种Newbonnet对IG-1,其正反交二代抗病植株与感病植株的比例为63∶1,说明,这些抗病品种对相应的IB-1、IE-1k和IG-1分别存在3对独立遗传的显性抗病基因,出现重叠作用的遗传关系。抗病品种特青与抗病品种Katy,抗病品种特青与感病品种LaGrue,抗病品种Katy与感病品种Newbonnet对IB-1,抗病品种特青与感病品种Mars和感病品种Lagure,抗病品种Katy与感病品种Mars和感病品种Lagure对IG-1,其正反交杂交二代抗病植株与感病植株的分离比例符合15∶1的比例,说明,这些抗病品种对相应稻瘟病小种存在两对独立遗传的显性抗性基因,出现重叠作用的遗传关系。抗病品种Mars与感病品种Katy、感病品种Lagure和感病品种Newbonnet对IE-1k,其杂交一代表现感病,正反交杂交二代抗病植株和感病植株的分离符合7抗︰9感的比例,说明,品种Mars存在两对隐性抗病基因,感病品种Katy、Lagure和Newbonnet与抗病品种Mars的后代出现两对显性感病基因互补作用的遗传关系。抗病品种特青与感病品种Mars,抗病品种Katy与感病品种Mars及LaGrue对IB-1,抗病品种特青与感病品种Katy、LaGrue和Newbonnet对IE-1k,抗病品种Katy、Mars和Newbonnet与感病品种LaGrue对IG-1,其正反交二代的抗病植株与感病植株的比例为3︰1,说明,这些品种对IB-1、IE-1k和IG-1的抗性分别存在1对显隐性基因遗传关系。感病品种Mars、La-Grue、Newbonnet对IB-1和感病品种Katy、LaGrue、Newbonnet对IE-1k,其正反交二代全为感病植株,说明,这些感病品种分别对IB-1、IE-1k的感病基因是等位的。

Resistance Inheritance of Five Cultivars to Rice Blast Races IB-1, IE-1k and IG-1 of USA

In order to research the inheritance of rice blast(Magnaporthe grisea) resistance of five cultivars to three major races of IB-1,IE-1k and IG-1,four American cultivars,Katy,Mars,LaGrue,and Newbonnet,and one Chinese cultivar,Teging in a complete diallel design was conducted in University of Arkansas at Pine Bluff,USA in 2008 and 2009.The parents,F1 and F2 were inoculated with these three races separately to test blast responses in the greenhouse of Rice Research Center in Stuttgart,Arkansas,USA in 2008 and 2009.Results: Teqing was resistant to all the three races.Katy was resistant to IB-1 and IG-1,but not to IE-1k.Mars was resistant to IE-1k,but susceptible to the other two.LaGrue was susceptible to all the three races.Newbonnet was susceptible to IB-1 and IE-1k,but resistant to IG-1.Experimental data showed six types of segregation ratio in the F2 progenies of the complete diallel crosses: 1) 63 R∶1 S indicated three dominant genes independently responsible for blast resistance;2) 15 R∶1 S suggested two dominant genes independently responsible for blast resistance;3) 7 R∶9 S suggested two genes working dominantly and complementarily resulting in blast susceptibility;4) 3 R∶1 S fitted in the single dominant gene model controlling blast resistance;5) 1 R∶0 S indicated allelic genes in two resistant parents;6) 0 R∶1 S indicated allelic genes in two susceptible parents.In most cases,resistant gene(s) was dominant over susceptible regardless of parents and blast races with only one exception.Susceptible F1 derived from resistant Mars with susceptible Katy,LaGrue and Newbonnet,respectively,indicated that the resistant gene(s) to race IE-1k in Mars was recessive.The recessive resistant gene model was verified by the segregation ratio of 7 R∶9 S in all F2 progenies from those F1 hybrids.Further more,this segregation ratio suggested that the two genes were complementarily involved.No differences of blast segregation between reciprocal crosses from any cultivars to any blast race were observed.Therefore,cytoplasm was not involved in the inheritance of blast in rice.