Comparative efficacy of diallel, partial diallel and line x tester analyses in the study of gene action in rice (Oryza sativa L.)

Comparative efficacy of diallel (Method 2 and 4 Model 1), partial diallel (sample size more and less than n/2) and line x tester analyses were studied to understand the nature of gene action of 14 traits (both quantitative and qualitative) affecting grain yield in rice. Both the methods of diallel analysis and partial diallel analysis with “s” equal to 6 (i.e. more than n/2) gave similar and comparable results. The nature of tester parents played a significant role in the estimates of gene effects. Line x tester analysis using tester parents with broad genetic base gave results fairly close to the diallel and partial diallel analysis. Hence, it was concluded that the line x tester analysis with profusely selected testers or partial diallel analysis with sample size equal to more than n/2 may be preferred to screen a large number of genotypes.