Evaluation of Forage Yield Stability of Advanced lines of Grass pea (Lathyrus sativa L.) by Parametric and Non- parametric Methods

In order to evaluate the stability and response of advanced lines of grass pea under rainfed conditions¡ fourteen lines were studied in a randomized complete block design with three replications at three research stations located in Khoram Abad¡ Kermanshah and Gachsaran during 2005-2008. Based on combined ANOVA analysis the effects of line¡ year × location¡ line × location and line × year × location were significant. Forage yield stability has determined by some parameters including Eberhart & Russell¡ Wrick’s eco-valance¡ Finlay and Wilkinson¡ coefficient of variance¡ stability variance¡ sum rank and yield stability. Based on Eberhart and Russell parameter the lines 6¡ 10¡ 13 and 2 were identified as stable lines. The regression coefficient of lines 1¡ 2¡ 5¡ 9. 12 and 14 were equivalent b = 1. Based on Wrick’s eco-valance and stability variance parameters¡ the lowest values were related to lines 6¡ 7¡ 1 and 2. Based on coefficient of variance the lines 1¡ 5¡ 9 and 12 had higher stability. In the terms of sum rank lines 1¡ 9 and 12¡ were selected as desirable lines. Also¡ in yield stability method the lines 3¡ 9¡ 5 and 12 had the most stability. Despite the differences in the results of various stability parameters¡ lines 1 (Sel. 515)¡ 5 (Sel. 689) and 9 (Sel. 554) with averages forage yields of 5459.70¡ 5669.19 and 5687.85 kg/h were identified as stable lines as well as adapted to rainfed conditions.