Genotype × Environment Interaction and Yield Stability Analysis in Ridge Gourd (Luffa acutangula L.) Using AMMI and GGE Approaches

Abstract

Ridge gourd (Luffa acutangula L. Roxb.) is an economically important cucurbit vegetable cultivated widely in tropical and subtropical regions; however, limited information is available on yield stability across seasons. The present study aimed to assess genetic variability, genotype × year interaction, and yield stability of 64 ridge gourd genotypes evaluated over three consecutive years in a randomized block design with three replications. Pooled analysis of variance revealed highly significant (P ≤ 0.001) differences among genotypes for yield and its component traits, indicating substantial exploitable genetic variability. The effects of year and genotype × year interaction were also significant for most traits, highlighting the influence of seasonal variation and differential genotypic response across years. To elucidate interaction patterns, Additive Main Effects and Multiplicative Interaction (AMMI) and Genotype plus Genotype × Environment (GGE) biplot analyses were performed. The AMMI model showed that the first two interaction principal component axes captured 100% of the interaction sum of squares, enabling identification of stable genotypes. GGE biplot analysis ((PC1 = 65.21% and PC2 = 22.73%, totaling 87.94%)) effectively discriminated genotypes based on mean yield and stability, revealed “which‑won‑where” patterns, and identified ideal genotypes namely RDG‑35 for E2, VRRG‑27‑1 for E3, and VRRG‑8‑17 for E1combining high productivity with wide adaptability. The integration of pooled ANOVA with AMMI and GGE approaches proved efficient in selecting superior and stable genotypes. The findings provide valuable insights for ridge gourd breeding programs focused on developing high‑yielding and widely adapted cultivars under variable environmental conditions.