INTEGRATED ANALYSIS OF GENOTYPIC PLASTICITY FOR ENHANCED PHOSPHORUS USE EFFICIENCY IN CHICKPEA (Cicer arietinum L.)

Abstract

Phosphorus (P) limitation is a major constraint in crop productivity, emphasizing the need for genetic improvement of phosphorus use efficiency (PUE) for sustainable agriculture. During 2024-25, thirty-three chickpea genotypes were evaluated under low and adequate P conditions to assess genotypic plasticity and identify the efficient genotypes using PUE index, principal component analysis (PCA), and multi-trait genotype-ideotype distance index (MGIDI). The PUE index ranked genotypes across the contrasting P regimes, PCA summarized trait covariation to highlight efficient multivariate profiles, and MGIDI integrated multiple traits to estimate the distance from an ideal genotype. Two-way ANOVA revealed significant genotype, treatment, and their interaction effects. Under low P conditions, shoot phosphorus concentration declined by 45.6%, while phosphorus assimilation efficiency increased by 82.7%, and root dry weight by 62.7%, indicating adaptive biomass allocation to the roots. Strong positive trait associations were observed across both P regimes, with biomass and P traits varying co-ordinately. Across all the methods, genotypes IG 5860, Pusa 3022 (BG 3022), and PG 0515 consistently emerged as superior genotypes. Notably, no cultivar surpassed the efficient check IG 5860, reinforcing its value as a donor for PUE breeding. These convergent rankings validate the integrated approach as a reliable strategy for prioritizing chickpea genotypes under low P stress.