Impact of Humic Acid and Sulphur application on growth and yield of Indian Mustard under variable Water moisture regimes

Abstract

Indian mustard (Brassica juncea L.) is an important oilseed crop cultivated in various regions of the world, particularly in India. However, its productivity faces limitations due to various abiotic factors, notably variable soil moisture. This study aimed to explore the influence of humic acid and sulphur application on Indian mustard growth and yield within different moisture regimes. A field experiment was conducted in rabi season, employing a split plot design with four replications. Four moisture treatments were imposed: (1) no post sowing irrigation, (2) one post sowing irrigation (3) two post sowing irrigation and (4) three post sowing irrigation. Within each moisture regime, four treatment groups were established: (A) control (no application), (B) humic acid alone, (C) sulphur alone, and (D) a combination of humic acid and sulphur. The results revealed significant improvements in various growth and yield parameters when humic acid and sulphur were applied, particularly under moisture stress conditions. Application of humic acid and sulphur enhanced root development, chlorophyll content, and photosynthetic rate, which ultimately led to increased plant height, leaf area, and biomass accumulation. Notably, the combined application exhibited synergistic effects, resulting in the highest yield increments, especially under severe moisture stress. This study provides valuable insights into the potential advantages of incorporating humic acid and sulphur as soil amendments in Indian mustard cultivation, particularly in moisture-variable regions. The results highlight the combined application’s effectiveness in mitigating water scarcity effects, thereby promoting sustainable agriculture and bolstering food security.