Effect of drought stress on agronomic traits of different rapeseed lines.

摘要

To study the crucial agronomic traits of rapeseed under stress conditions, 100 haploid lines derived from the cross spring line "Yudal" and winter line "Darmor" along with the parents were evaluated using a simple lattise design with two replications under drought stress conditions in University of Gonbad during 2010-2011. Measured traits were days to flowering, plant height, height of lowest primary effective branch, length of main inflorescence, seed yield, 1000-seed weight, seeds per pod, pod length, pod beak length, pod thickness and pod density. There was a large variation in the population for different traits which was due to the fact that their parents had multi forms and a different genetic background. Correlation analysis showed that days to flowering and height of lowest primary effective branch had the highest negative and positive correlation with grain yield, respectively. The regression and path analysis showed that days to flowering, height of lowest primary effective branch and plant height as important components had the highest direct effect on grain yield. The reductions in grain yield and 1000-kernel weight were affected mostly by drought stress. Nonetheless, some agronomic traits such as pod thickness, pod length and beak length were not significantly changed under drought stress. Doubled haploid lines were grouped using principal components analysis based on drought tolerance indices. The first two principal components explained 98 percent of data variation.