Assessment of Physiological Traits and Yield Potential in Mungbean (Vigna radiata L.) Genotypes under Diverse Environmental Conditions using Infra-red Gas Analyzer

Background: Mungbean is a significant legume crop renowned for its high nutritional value and adaptability to diverse agro-climatic conditions. However, the current environmental changes may have numerous biochemical and physiological impacts that could influence the productivity of this crop. The yield of mungbean is generally low, often attributed to physiological constraints in addition to its genetic makeup. The current study aims to assess the net photosynthetic rate, transpiration rate, photosynthetic water use efficiency and seed yield of 35 mungbean genotypes under four distinct environmental conditions. Methods: Field trials were conducted using a randomized block design with thirty-five mungbean genotypes and three replications across four distinct environments at Swami Keshwanand Rajasthan Agricultural University, Bikaner, Rajasthan during the summer of 2019 and Kharif season of 2019-20. Net photosynthetic rate and transpiration rate were measured on the abaxial surface of the third fully extended leaf from the topmost at 45 days after sowing, between 9:00 AM and 11:00 AM, using a handy photosynthesis system equipped with an infrared gas analyser. Result: Significant variations were observed among genotypes and across environments. Genotype IC-52087 exhibited the highest Pn (53.90 µmolm-²s-1), while MH-421 demonstrated superior WUE (18.07 µmolCO2mol-1H2O). The findings highlight the influence of environmental conditions on physiological traits and provide insights for breeding programs aimed at improving drought tolerance and yield potential in mungbean.