Agricultural Research Journal

Climate change has had a profound impact on agriculture. Given the current trend of rising temperatures, an investigation was conducted to assess the influence of weather variability on mustard crop. Two different varieties, Pusa Bold and Varuna, were evaluated across varying dates of sowing: October 15^th, November 10^th, and December 5^th. Agroclimatic indicators such as Growing Degree Day (GDD), Helio-thermal units (HTU), Photo-thermal units (PTU), and Photo-thermal Index (PTI) were employed to examine their correlation with yield under different sowing conditions. The findings revealed that the duration between various phenological stages, from emergence to physical maturity, was longest in the October 15^th sowing (154 days), followed by November 10^th (132 days), and December 5^th (113 days). This reduction in duration for later-sown mustard crops may be attributed to higher temperatures (30-35°C) during the reproductive phase, which led to forced maturity. Across all three sowing dates, the Varuna variety took longer to reach maturity (135 days) compared to Pusa Bold (131 days). Mustard crops sown on October 15^th required more thermal and heat units compared to those sown on November 10^th and December 5^th, owing to their longer maturation period. Yield attributing characters such as the number of siliqua per plant, number of seeds per siliqua, 1000-seed weight, biological yield, and seed yield were significantly higher in early-sown crops, followed by those sown in the normal and late periods.