The objectives of this study were to investigate the comparison among non-parametric stability statistics and to evaluate seed yield stability of the sixteen soybean genotypes across four locations during the 2016, 2017 and 2018 growing seasons in Egypt. All trials were laid down in a randomized complete block design (RCBD) with three replications. The AMMI analysis showed ahighly significant effect of genotype (G), environment (E) and G x E interaction (GEI). The major contributions to treatment sum of squares were GEI, followed by G and E. The AMMI analysis also partitioned the total GEI component into eleven PCAs and Residual. The first eight PCAs were highly significant and accounted for about 99.56% of the total GEI. Based on the static and dynamic concepts, the results of spearman’s rank correlation and PCA showed that stability measures could be classified into three groups. The non-parametric stability statistics i.e., YSi, KR, TOP, RSM and δgy related to the dynamic concept and strongly correlated with mean seed soybean yield of stability. While, the other non-parametric stability statistics (Si(1) ,Si(2) ,Si(3)  and Si(6),NPi(1) ,NPi(2) ,NPi(3) and NPi(4)  , δr, MID, LOW) represented the concept of static stability, which were influenced simultaneously by both yield and stability. The non-parametric stability statistics in each the groups I, II, and III were positively and significantly correlated with each other, thus; any of these parameters could be considered as appropriate alternatives for each other. According to cluster analysis, soybean genotypes G6, G4, G8, G11, G9, G1, G7 and G2 were more stable varieties on the basis of mean seed yield and non-parametric stability statistics. In conclusion, both yield and stability should be considered simultaneously to exploit the useful effect of GEI and to make the selection of genotypes more precise and refined. Thus, the YSi, KR, TOP, RSM and δgy were more useful statistics in soybean breeding programmes and could be useful alternatives to parametric stability statistics. According to most non-parametric stability statistics, the genotypes G6 and G11 were more stable coupled with high seed yield; therefore, these genotypes might be used for genetic improvement of soybean and they must be released in studied regions and other regions in Egypt.

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Sids-19). Three sowing dates (October 15 th , November 1 st and November 15 th) were used. The results of the combined analysis of the two growing seasons 2016/2017 and 2017/2018 showed that, number of days to both flowering and maturity and number of branches were significantly affected by sowing date. The productivity traits were significantly affected by sowing date, specially, seed yield per faddan. The results revealed significant differences among the eight faba bean genotypes in their performance in both of number of days to flowering and maturity. The earliest faba bean genotypes were Giza-843, Sakha-3 and Giza-716 in both Sids and Mallawy. It was found that, late sowing showed a shorter period until to maturity. Genotypes produced higher seed yield/plant at the 2 nd sowing date (November 1 st). Genotypes produced heaviest 100-seeds in the 1 st sowing date, because, plants stayed longer to reach maturity, relative to those planted in both of Novamber1 st or November 15 th , since seeds given much time to grow. Sakha-3 in both Mallawy and Sids, attained the highest seed yield (ton fad.). The second sowing date (November 1 st) was most proper and any of Sakha-1 and Sakha-3 Sids-19 might be adopted to Middle Egypt.