Title: Compatibility and stability of rice promising lines with the origin of local cultivars in intermittent irrigation condition
Author: Mehrzad Allahgholipour
Abstract; Due to the decreasing trend of rice cultivation in the whole country, especially in the two provinces of Guilan and Mazandaran, increasing rice production in the current situation due to water resources limitation in recent years will not be possible and to achieve this goal, a solution to increase production per unit area with optimal water consumption seems necessary. In this experiment, 15 local and improved cultivars with desirable quantitative and qualitative characteristics and proper growth period were evaluated in a randomized complete block design with 4 replications in four regions of Rasht, Ghazian, Cholab, and Nodeh during two cropping years (2016- 2017). The results of the combined analysis showed that the share of the main effect of the environment for all traits was greater than the share of genotype-environment interaction. The results of the GGE biplot showed that the first two components explained 85.38% and 8.68%, of the total variation. Since the selection of superior genotypes for different environments had to take into account both yield and stability factors, genotypes were then ranked based on grain yield and stability, mean rankings were estimated and then genotypes were re-ranked according to mean rankings. Considering the rank of genotypes in terms of grain yield and stability, combined RI18442-66 with first rank and RI18437-92 with the second rank were selected as superior genotypes. In this experiment, the grain yield of studied genotypes ranged from 5.67 to 7.71 t/ha. Results of estimation of mean traits in cultivars evaluated in four years in two years (8 environments) showed that two lines RI18442-66 with 7.71 t/ ha and RI18437-92 with 6.44 t/ha were selected as superior lines among other genotypes due to moderate amylose content, proper growth period, high grain yield, average plant height, and water intake.
Keywords: Interval Irrigation, Rice, Stability, GGE Biplot, Grain Yield