پايداري عملكرد دانه در ژنوتيپ هاي بهاره كلزا

Stability of seed yield in spring rapeseed (Brassica napus) genotypies

The present study was conducted to determine high yielding rapeseed cultivars adapted to different agroclimatic conditions. The 22 spring type rapeseed genotypes as well as a check cultivaer (Sarigol) were evaluated in a randomized complete block design with four replications in four locations for two cropping seasons (2000-02). Simple ANOVA of yield showed significant differences among the genotypes. In combined analysis of variance (based on 8 environments), the effects of locations and years were not-significant, but interaction effect of year x location was highly significant. Differences among genotypes were also significant, while the mean squares of genotype location and genotype * year interactions were not significant , however the mean squares of genotype * year * location interactions were significant. According to the Eberhart and Russellʹs, mether genotype No. 21 (Hybrid Hyola401) with highest yield , coefficient of regression equal to unity and non-significant deviation from regression was the most stable genotype. Differences in grain yield of genotypes No.2 (S-2), No. 20 (Hyola308) and No. 21 (Hyola401) were not significant, Therefore recognized as genotypes with average stability. Based on coefficient of variation (CVi), genotype no.3 (Cyclone) was one of the three stable genotypes followeing to Hyola 401 and S-2, coefficient of determination (R2) of these genotypes were highly significant . Finally, based on simultaneous selection for yield and stability, the high yielding genotypes No. 21 (Hyola401), No. 2 ( S-2) and No. 20 (Hyola308) could be recominended Roz target enivaronments.