Evaluation of Variation at Barley Inbred Lines (Hordeum vulgare L.) using SIIG Index

Genetic diversity is the base for survival of plants in nature and for crop improvement. Diversity in plant genetic resources provides opportunity for plant breeders to identify new and improved cultivars with desirable characteristics. In order to study the variation of barley inberd lines using the selection index of ideal genotype (SIIG), 108 pure lines in the non-repeating Augment design with four controls in three blocks were evaluated in the farm of Darab Agricultural and Natural Resources Research Station in cropping year of 2017-18. The results of ANOVA showed a significant difference among studied lines for all traits (except for the days to flowering) which indicated the existence of variation among the lines. The results of REML analysis showed that, the lowest heritability of traits was related to 1000-kernel weight (0.001) and the highest heritability was related to days to maturity and days to flowering (0.79 and 0.77), respectively. The results of the SIIG index indicated that line 18 with the highest SIIG (0.767) was the best and line 75 with the lowest SIIG (0.149) was the weakest line in this study. In order to evaluate the efficiency of SIIG index in selecting the best lines for grain yield, 1000 kernal weight and plant height, the lines were grouped according to SIIG index in 6 categories. The results showed that as the amount of SIIG index decreased, grain yield, 1000 kernal weight and plant height were also decreased, but there was no significant change in the days to flowering and days to maturity. Also, the results of grouping of lines based on SIIG showed that the average grain yield of groups 1, 2 and 3 was higher than the average yield of the three controls: Nimroz, Auxin and WB-94-4. Also, there was relative conformity between the SIIG index and cluster analysis in this study. This research showed that the SIIG index was able to categorize the genotypes according to the three traits of grain yield, 1000 kernal weight and plant height, simultaneously.