Assessing onion genotypes stability and potential in diverse Indian environments

The current study investigates how genotype by environment interaction (GEI) complicates superior cultivar selection in onion breeding. Employing a randomized block design with three replications, we assessed GEI effects on onion yield and identified adaptable, stable genotypes. The sensitivity of onion genotypes to environmental changes significantly influences yield and quality, necessitating adaptability across diverse climatic conditions. We conducted multilocation trials evaluating 28 onion genotypes across four distinct locations, each representing varying environmental factors. Through phylogenetic analysis, genotypes were categorized into four clusters: cluster I (3), cluster II (4), cluster III (15), and cluster IV (6). Rigorous assessment of yield performance, employing additive main effects and multiplicative interaction models, particularly the AMMI model, revealed five genotypes demonstrating remarkable stability and potential across diverse environmental conditions: RO-1626, RO-1623, RO-1639, RO-1625, and RO-1627. Notably, genotypes from cluster II exhibited the highest marketable yield (277.06 q/ha) and total yield (295.66 q/ha), indicating adaptability to varied environmental conditions. These findings hold promise for breeding high-yielding onion varieties resilient to diverse environments, ensuring stability, adaptability, and quality in cultivation.