Thermo-temporal Changes in Soybean Productivity under Rainfed and Irrigated Conditions in Pakistan

Temperature and precipitation significantly influence the cultivation of Soybean (Glycine max L.) across the globe. Therefore, the current investigation was planned to evaluate the impacts of these climate change indicators on the phenology and yield of this oilseed legume. For this purpose, the experiments were conducted during June-September of 2019 and 2020 in the rainfed and irrigated regions of Pakistan. Four soybean cultivars, Rawal‑1, Ajmeri, NARC‑2, and NARC-16, were planted on three sowing dates, viz. 15 June, 30 June, and 15 July. The impacts of water availability and climatic conditions were assessed by a relationship between planting dates and phenological and yield parameters. Results revealed that flowering, pod formation, and maturity days were more remarkable in plants cultivated on June 15, while late plantation took the least days to mature. Leaf area index (LAI) and total dry matter (TDM) accelerated 50–70 days after planting. The highest LAI and TDM were observed in the NARC-16 cultivar under all environments, but it performed exceptionally well under irrigated conditions. A similar response was observed in the yield of the early planted NARC-16 cultivar, whereas Rawal‑1 plants produced the least LAI, TDM, and yield regardless of sowing time and environment. The cultivar NARC-16 had a promising yield when sown during the 2nd–3rd week of June and performed equally better under rainfed and irrigated conditions. Therefore, this cultivar is recommended for cultivation for improved production of Soybean in the irrigated and rainfed regions of Pakistan.