Selection of Barley Superior Lines with Desirable Agronomic Characteristics Using the Selection Index of Ideal Genotype (SIIG)

This study was conducted to investigate the phenotypic diversity of 108 pure barley lines in Augment design with four controls in six blocks in the farm of Darab Agricultural Research Station (2020-2021). In order to select the best lines in terms of yield and other traits, SIIG index was used. The results of restricted maximum likelihood (REML) analysis showed that the lowest and highest levels of broad-sense heritability were related to the number of days to the spike emergence of (0.21) and the number of days to maturity (0.97), respectively. Based on the SIIG index, the studied lines were grouped into five categories. The results of SIIG index showed that L86 and L38 lines with the highest (0.640) and lowest (0.249) values of SIIG were the best and weakest lines, respectively. The results of grouping the lines based on SIIG index showed that group one and two lines and lines L22, L62, L80, L64, L51, L10, L96, L73, L81, L100, L69 and L97 from group three, were the best in this study and can be considered for further investigations. Overall, the results showed that SIIG index was able to classify genotypes based on grain yield, spikes/m2, seeds/spike, spike weight and plant height simultaneously, and also there was a relative compliance between the SIIG index and principal component analysis. Therefore, SIIG index is a suitable method for selecting ideal genotypes based on several traits simultaneously.