بررسی کارایی گزینش هم‌زمان برای پایداری و عملکرد بالا در جو و مقایسه آن با سایر شاخص‌های پایداری

The interaction of genotype × environment effect, because of disordering effect on genotypes selection has special importance in plant breeding programs. Therefore to better selection, yield and yield stability might be considered simultaneously. In order to study of grain yield stability and the evaluation of different selection methods efficiency, 18 advanced barely lines were studied in four locations, Moghan, Gorgan, Gachsaran and Kohdasht, for three years during 2005 to 2007 growing seasons. The experimental design in all of the locations and years was a completely randomized block design with four replications. Results of three years yields in four locations showed that lines No. 1 & 14 with 4256 and 4205 kg/ha and line No.6 with 3289 kg/ha produced the highest and lowest grain yield, respectively. Whereas control cultivar (LB) produced 3609 kg/ha grain yield. Using yield-stability (YSi) index, lines No. 14, 1, 11, 2, 12, 5, 18, 15 and 9 were selected as stable lines with high yields, respectively. The line No. 14 with YSi=19 and lines No. 1 & 11 with YSi=18 were selected as the best lines. Whereas the control cultivar (LB) had YSi=-2. Also line No. 10 was selected as the weakest line in yield and stability surveys. Mean comparing analysis among yield means of selected lines using four different selection procedures, showed no significant difference between them, but the order of selected lines was different in four methods. This could be important in the introduction of stable cultivars. Therefore due to higher emphasis of stability parameter in YSi calculating, YSi index is suitable and confidence for selection of high yielding and stable genotypes.