Study of yield and yield components in ten cultivars of rapeseed (Brassica napus L.) in Birjand region

In order to study the correlation between morpho-phonological and quantitative traits with yield and determination the most important traits effect on yield, 10 varieties of rapeseed were evaluated in randomized complete block design with 3 replications in climatic condition of Birjand region. Variance analysis showed significant difference between varieties for all traits except height and auxiliary stem number traits. Correlation analysis showed that the numbers of pods per plant and harvest index have the most of positive and significant correlation coefficient and the days to 50% flowering and days to 90% maturity traits have the most of negative and significant correlation coefficient with economical yield. The stepwise regression analysis showed that the days to 50% flowering, auxiliary stem number and number of pods per plant were more important traits. Path analysis showed that the number s of pods per plant and auxiliary stem number have the most of positive effect and days to 50% flowering has the most negative effect on yield. Factor analysis showed that 3 factors illustrated the most of variation. The first factor with name phenologic of yield was more important than other factors. This factor contains days to 50% flowering, days to 90% maturity, harvest index and economical yield traits.