Comparative analysis of phenological and yield-related traits in early and late vigor genotypes of chickpea (Cicer arietinum L.)

Abstract

Chickpea (Cicer arietinum L.) is a vital pulse crop for global food security, but its productivity is often constrained by environmental stresses. Vigor type, determined by early leaf area development, is a key determinant of crop establishment and final yield. This study aimed to dissect the physiological and yield trade-offs between early and late vigor chickpea genotypes. A two-year field experiment was conducted using two late vigor (ICC 283, ICC RIL04-260) and two early vigor (ICC 8261, ICC RIL04-268) genotypes, evaluated in a replicated completely randomised block design. Data were recorded on phenology (days to flowering and maturity), growth (shoot dry weight), and yield components (pod number, pod weight, seed number, seed yield, and harvest index). Results revealed that late vigor genotypes flowered and matured significantly earlier (44-50 and 83-90 days, respectively) than early vigor genotypes (56-62 and 100-108 days). As hypothesized, early vigor genotypes exhibited superior vegetative growth, with shoot dry weight 21-24 g compared to 15-18 g in late vigor types. Conversely, late vigor genotypes compensated by producing a significantly higher number of pods (46-53) and seeds (39-44) per plant. However, early vigor genotypes, likely due to larger Kabuli seed characteristics, achieved significantly higher pod dry weight per plant (11-13 g), seed yield per plant (9-11 g), and harvest index (0.44-0.48) compared to late vigor genotypes (6-8 g, 5-7 g, and 0.36-0.41, respectively). Analysis of variance showed highly significant (p<0.01) genotypic differences for all traits except pod number (p<0.05). High heritability estimates (0.58 to 0.78) indicated a strong genetic control over these traits. The study concludes that while early vigor genotypes are superior in direct yield and partitioning efficiency, late vigor genotypes offer a strategy for drought escape through shorter life cycles, slower water extraction at earlier stages of crop cycle, conservative canopy development and a different yield architecture based on prolificacy. These findings provide crucial insights for breeders to develop chickpea varieties tailored for specific agro-ecological zones and cropping systems.