EXPLORING GENETIC AND ENVIRONMENTAL EFFECTS ON NUTRITIONAL AND FUNCTIONAL COMPONENTS IN BARLEY (HORDEUM VULGARE L.) GRASS POWDER FOR TWO-YEAR MULTIVARIATE EVALUATION

This study evaluated the genetic variability and environmental influence on nutritional and functional components -flavonoids, -aminobutyric acid (GABA), alkaloids, and protein-in grass powder from 43 barley (Hordeum vulgare L.) genotypes grown over two consecutive years in Kunming, Yunnan, China.Field trials were conducted in 2021 and 2022 using a randomized complete block design with three replications.Two-year ANOVA revealed highly significant genotypic effects (p < 0.01) for all traits, indicating substantial genetic variability.Year effects were significant for flavonoids, GABA, and alkaloids, but not for protein, indicating trait-specific environmental sensitivity.Flavonoid content ranged from 97.69 to 242.24 mg/100 g in year 1 and from 102.38 to 202.29 mg/100 g in year 2. The GABA content increased from 201.75 mg/100 g to 233.62 mg/100 g, while alkaloids contents decreased slightly from 107.82 to 100.49mg/100 g.Protein content rose marginally from 32.84% to 33.91%.Significant genotype year interactions for flavonoids and GABA (p < 0.05) highlighted trait instability under varying conditions, while protein remained stable across years.Correlation matrix analysis showed strong positive associations between flavonoids and GABA, and moderate correlations with alkaloids, suggesting shared stress-responsive biosynthetic pathways.Protein showed no consistent correlation with secondary metabolites.PCA biplots explained 78.06% (Year 1) and 77.58% (Year 2) of the total variance, effectively discriminating genotypes.Genotypes G41, G11, G3, G7, and G31 exhibited superior trait profiles, while G18, G26, and G34 consistently ranked lowest.Stable genotypes identified in this study provide a foundation for cultivar development aimed at improving human and animal health.These findings provide valuable insight for breeding nutrient-enriched barley cultivars for functional food and feed applications.