Selection of barley pure lines with high yield and desirable agronomic characteristics in warm areas of Iran

Barley (Hordeum vulgare L.) is one of the most important plants in the cereal family after wheat, rice and corn. Barley is the second most important crop in Iran after wheat in terms of agricultural value and nutrition. The purpose of this study was to evaluate and select superior lines with high yield, early maturity and dormancy resistance in warm regions of the south and north of the country using the selection index of ideal genotype (SIIG).

In order to selection of pure barley lines with high yield and desirable agronomic characteristics in the warm regions of the south and north of the country, 108 pure lines in the non-repeating Augment design with four controls (Norooz /Sahra, Auxin, Nobahar and WB-96-19) in three blocks, in the Centers for Agricultural Research and Education and Natural Resources Fars (Darab), Ahvaz, Sistan (Zabol) and Golestan (Gonbad) were evaluated during 2019-20 cropping year.

The results of restricted maximum likelihood (REML) analysis showed that the heritability of grain yield in Gonbad, Ahvaz, Darab and Zabol were 0.993, 0.258, 0.498 and 0.063, respectively. The results of correlation analysis showed that there is a positive and significant correlation between SIIG index and plant height, 1000-kernal weight and grain yield in all regions. SIIG index showed that 21, 28, 16 and 5 lines in Darab, Ahvaz, Zabol and Gonbad, respectively, with high SIIG index value (0.6-0.9) were the best lines. Based on the results of the average SIIG index of lines 68, 102, 44, 66, 13, 47, 16, 34, 46, 99, 25, 65 and 35, respectively, with SIIG value higher than 0.500 were the best lines in most regions, so they are recommended for cultivation in later years and for advanced testing and compatibility. In order to evaluate the efficiency of SIIG index in selecting the best lines in terms of grain yield, 1000 kernel weight, plant height and early maturity, the studied lines were grouped based on SIIG index in different regions. The studied lines were classified into 6, 7, 8 and 7 groups in Darab, Ahvaz, Gonbad and Zabol, respectively.

Based on the results of the average SIIG index in all regions, 16 lines with the highest average value of the SIIG index were top lines in most regions. Selected lines in each region can be recommended for experiments in that region, and lines with the highest SIIG values in most regions for additional testing in all introduced regions in later years.