AMMI and GGE biplot analysis of seed protein concentration, yield, and 100-seed weight for chickpea cultivars and breeding lines in the US Pacific Northwest

Abstract

Greater global demand for plant-based protein has made increasing protein concentration in chickpea (Cicer arietinum L.) an important breeding objective. In this study, 17 kabuli chickpea genotypes were evaluated for seed protein concentration (SPC), yield, and 100-seed weight (HSW). All entries were planted in 2020 and 2021 at four locations in Washington. The mean of all entries for SPC was 20.3%. Genotype (G), location (L), G × year (Y), and L × Y (E) effects were significant for each trait. Year (Y) effects were significant for SPC and yield and accounted for the greatest percentage of total variance for both traits. Additive main effects and multiplicative interactions and genotype (G) main effects and genotype (G) × environment (E) interaction (GGE) biplot analyses were used to identify stable genotypes and to dissect GEI in chickpea. GGE biplot analysis indicated G + G × E effects accounted for 78.69%, 64.01%, and 95.99% of the total variation for SPC, yield, and HSW, respectively. Environments tended to be positively correlated for all three traits and biplot analysis suggests three mega-environments. Three genotypes, CA0790B0429C, CA13900147C, and Sierra, consistently had high SPC but low yield. Billy Beans was superior for yield. Nash and CA15940057C consistently had high HSW. No genotype had high SPC, yield, and HSW. Significant positive correlations (r > 0.6) were observed between SPC, days to mature, and plant height. It will be challenging to make substantial gains in SPC using only the genotypes evaluated in this study.