Correlation and Path Analysis Yield and Important Traits of 12 Spring Rapeseed Cultivars( Brassica napus L)

This study was conducted to analyze the correlation among grain yield and a number of important traits in twelve spring rapeseed (Brassica napus L.) cultivars at Dezful research station in Safi Abad, from 2009 to 2010. A randomized complete block design with four replications was used. Results analysis of variance showed that significant difference between cultivares for all parameters in expriment, indicated a geneticaly difference between cultivares.The correlation coefficients among the grain yield and 1000-grain weight and grain number/pod were positiveand significant(0.74** and 0.72**, respectively). Grain yield and days to maturity, days to flowering, plant height and oil percent were correlated negatively. According to stepwise regression grain yield trait is considered by dependent variables and other traits by independent variables. Model determination coefficient is R2=0.934. The highest level of determination coefficients were for 1000-grain weight and the number of grain per pod(0.547and 0.177, respectively). The results of path analysis indicated that the number of grain per pod and 1000-grain weight had the largest direct effect on the grain yield(1.10**and 0.41*, respectively) its seems possible to use the traits as a selection criteria in breeding programs for improving grain yield of spring rapeseedcultivars.