水稻穗型构成性状的相关与通径分析

通过对５个水稻品种和１０个杂种二代的穗型构成性状的研究表明，穗型构成性状之间存在着很强的相关关系；穗型构成性状与单株穗数多是较强的负相关；株高、出苗至抽穗天数与大多数穗型构成性状是显著的正相关。通径分析中所选性状对主穗粒重的回归估计的可靠度为９６．８％。其中，主要起直接作用的二次枝梗数和千粒重是第１位因子；主要起间接作用的一次枝梗数、一次枝梗平均长度、粒数／１０ｃｍ一次枝梗是第２位因子。根据试验结果，育种中直接对第一位因子加以选择，同时兼顾第２位因子，可望育成穗粒多，旦粒大的高产品种。

CORRELETION AND PATH ANALYSIS BETWEEN CHARACTERS OF RICE PANICLE STRUCTURE

Studies on characters of panicle structure of 5 rice varieties and 10F2showed that there were signifficant correlations between panicle structure characters,which had negtirecorrelation with panicle number per plant, positire correlation with days to heading and plantheight. In path analysis,about 96.8 of variation in grain weight in main panicle was determined by the panicle traits mentioned above.Among them secondary branch number andWeight per mil grain were first class facters with direct distribution to grain weight per panicle,get primary branch number and average Longth of primary branch and spiketet density were second cless factors with indirect effect on grain yield per panicle.In high yield breeding ofpaddy riec we should put the first class factors the most important place and in the same timegive some consideration to the Second class ones