Morpho-Physiological Performance of Glycine max (L.) Merrill an Oil Seed Crop Genotypes under Drought Stress

Abstract

Soybean‘s productivity is severely constrained by drought stress, particularly in rainfed agro-ecosystems, leading to significant yield reductions. Thus, the present investigation was conducted to identify drought-tolerant soybean genotypes based on a comprehensive evaluation of different morpho-physiological traits. A total of 60 soybean genotypes were assessed under drought stress conditions. The morpho-physiological analysis revealed presence of substantial genetic variability among the genotypes for the drought tolerance associated traits. Drought stress adversely affected plant growth and metabolic activities, indicating the sensitivity of soybean genotypes to water deficit circumstances at different phenological stages. Nevertheless, certain genotypes demonstrated adaptive responses enabling better performance under stress circumstances. The longest root system was recorded for the genotype SL-525 (36.0 cm). While the highest R/S ratio was recorded in genotype NRC127 (0.7777). The highest RWC was recorded in genotype JS 97-52 (68.72%) closely followed by AMS 2014-1 (65.86%), PS 1613 (64.88%), NRC-147 (64.77%) and RVS-24 (64.08%). Based on combined tolerance indices and trait performance, four genotypes viz., JS 97-52, AMS 2014-1, RVS-14 and NRC-147 were identified as drought tolerant. These genotypes exhibited superior morpho-physiological resilience and thus, hold promise for utilization of these genotypes to breed drought-resilient soybean cultivars by employing conventional or molecular breeding apporaches in future.