【摘要】 本研究用９个和４个抗性指标作为评定标准，对２１个水稻品种的抗瘟性进行了系统聚类分析。结果表明，按９个和４个抗性指标，２１个品种都可以较好地分成６类。两者的第４、６类所含的３个、１个品种相同，属感病：它们的其他４类所含的品种数略有差异。两者的第１类各含８个、９个品种，属抗至高度抗病，它们可用作育种抗源：两者的第２类各含３个、２个品种，属中感至中度抗病：两者的第３类各含３个、４个品种，属感至高度感病：两者的第５类各含３个、２个品种，属高度感病。结果亦表明，采用４个抗性指标可代替９个抗性指标，即用苗期病斑孢子层级指数、成株叶瘟严重度、产孢量和穗颈瘟严重率作抗瘟性评定标准进行系统聚类分析是较客观合理的。更多还原

【Abstract】 Nine and four resistant indexes used as resistant appraisal standards to rice blast in 21varieties were separately studied With the cluster analysis. The results showed that according to 9 and 4 resistant indexes, 21 rice varieties were divided into 6 groups,in which the 3 and 1 varieties were the same in both No.4 and No. 6 groups being susceptible, while the varieties in the other four groups were a little different in number. The 8 and 9 varieties in both of the first groups were from resistance to high resistance,which they can be used as resistant source of breeding. The 3 and 2 varieties in both of the second groups were from moderate susceptibility to moderate resistance, the 3 and 4 varieties in both of the third groups were form susceptibility to high susceptibility,and the 3 and 2 varieties in both of the fifth groups were high susceptibility.In addition, the results also indicated that it was quite objective and reasonable to take four resistant indexes instead of 9 resistant indexes, The number of sporulation, leaf blast severity at the adult stage,grads of spore layer scales of lesions at the seedling stage,and severity percentage of neck blast,were used as resistant appraisal to blast in rice varieties with cluster analysis.更多还原