Preliminary Evaluation of Breeding Lines of Bread Wheat in Yield Trial under Water Stressed Conditions Registration

Considering importance of season drought and shortage of water or no access to enough water for irrigation with the aim of releasing tolerant varieties to terminal drought this trial was performed. In this study 51 lines and varieties of bread wheat along with 3 check cultivars (Marvdasht, Cross Alborz and Azar-2) were planted under late season water stress conditions in three locations Kermanshah, Esfahan and Vararnin, These 51 entries were divided to 3 sets based on heading date from past evaluations, 17 entries each and along with above 3 checks each group included 20 genotypes. These 3 experiments showed by WS1-WS3 were planted in RCBD with 4 replications. These trials were irrigated in autumn once and due to rainfall were not irrigated till spring. Based on spring rainfalls one ( in case of Kermanshah and Varamin ) and two (in case of Esfahan) irrigations were done after cutting of rainfall so that every experiment was exposed to water stress in heading stage onward. The necessary assessments like response to winter cold, number of days to heading and maturity and assessment of phenotypic appearance in relation to response to drought were evaluated and recorded. After harvesting thousand kernels weight and grain yield per plot were recorded. Combined ANOYA was done for grain yield and means were compared using Duncan method (DMRT). Stability parameters; g, , S2i , CVj , b, , S2dj , W, and 82; which stand for genotypic mean, environmental variance, environmental variation coefficient, regression coefficie~t , v~ri_an~e of deviations from-regression, Wricke ecovalence and stability variance of Shukla respectively, were calculated for all genotypes in each experiment. Combined ANOVA showed a significant effect for location, genotypes and G*E interaction in all 3 experiments. Comparison of means showed the entries 7, 19,5, 18 and 16 with above 6 tons/ha grain yield in WS1 set. In this trial Marvdasht, Cross Alborz and Azar-2 were lied in 18'11, 191h and :W1h ranks for grain yield. Also genotypes Marvdasht , Cross Alborz and 13 were the most unstable genotypes and others almost had no significant role in G*E interaction variance. From WS1 set entries 5,7,10, '13 , 17,18 and 19 were selected based on all concerned traits including resistance to yellow rust. In case of WS2 entries 36 and 27 had outstanding grain yield above 6 tonslha. In this trial genotypes Marvdasht , Cross Alborz, 24 , 33 and 40 had more considerable role in G*E variance. The entries 27, 31, 32, 34 and 36 were selected considering also other characteristics. About WS3 entries 45, 51_, 52,46 and 60 were the best performers for yield. Genotypes 46 , 48 , 50 , 54 and 59 showed a more considerable role in G*E variance and others had less environmental variance. Entries 46, 54 and 60 were the selected lines frorn WS3_ The selected lines over all 3 experiments were considered to be evaluated more for adaptation in a two years regional trial across several locations in next crop season.