Title: Stability analysis of rice promising lines in regional yield trials
Author: Morteza Nasiri
Abstract: Evaluation of yield and agronomic characteristics of rice pure lines in different environments is a prerequisite for selecting superior lines for cultivar introduction. In this regard, seven pure lines (from crosses between Iranian and introduced cultivars) along with a selected line from Fajr and two control cultivars of Shiroudi and Keshvari were studied. The experiment was conducted in a randomized complete block design (RCBD) in four regions of Mazandaran province during two cropping years of 2017 and 2018. The results of the combined analysis showed that genotypes had significant effects on all of the studied traits except the number of tillers. Comparison of genotypic means showed that line No. 951 with 6623 kg.ha-1 had the highest yield in four regions and two years, which was statistically better than the control varieties. The results also showed that lines 952, 955, and 956 were statistically similar to 951. The studied lines had a higher growth duration (90 days from transplanting to harvest) than Keshvari and less than the Shiroudi cultivar. Among the investigated lines two lines 951 and 953 with 91 days from transplanting to harvest were similar to Keshvari. Results of yield stability analysis showed that line 952 with a regression slope of 0.9 and lines 953 and 956 with a regression slope of 1.2 had the closest slope. Thus, two lines 952 and 956 had yields of 6586 and 6468 kg/ha, the height of 115 and 122 cm, 1000-grain weight of 25 and 26 g, amylose of 19.4 and 23.7%, respectively, and with rick and Shukla stability of 2 and 1 were selected as best lines for field trials.
Keywords: Rice, adaptability, quality, yield, pure lines