ABSTRACT

This study evaluated the impact of climate factors on crop growth in the Hosur-1 micro watershed during the Kharif (June-September) and Rabi (October-March) seasons of 2023-2024. Key weather parameters, viz., rainfall, temperature and solar radiation were recorded with Kharif receiving 370 mm of rainfall with the highest in July (225 mm), and Rabi receiving 59 mm with the November (50 mm) getting the most rainfall. The average maximum temperatures during Kharif and Rabi were 33°C and 32°C, respectively. Experimental results for maize, groundnut, sorghum and cowpea showed the effects of these climatic conditions on grain yield and biomass. Calibration and validation of the DSSAT model indicated the following grain yield of specific cultivar in each crop; Maharaja-92 of maize yielded 8522 kg/ha, G-2-52 of groundnut produced 1436 kg/ha, HTJH-3206 of sorghum yielded 2549 kg/ha and the local cowpea variety yielded 520 kg/ha. Future weather projections (2025-2034) predict decrease in annual rainfall by 0.97% and a reduction in maximum temperatures by 1.13%. Seasonal analysis of simulations revealed decline in maize yields under future weather scenarios, with the Kaveri variety showing a 24% reduction in grain yield (from 7438 kg/ha to 5635 kg/ha) and a 23% decrease in tops weight. Similarly, the HTJH-3206 sorghum cultivar showed 11% reduction in seed weight, but an 8% increase in grain yield (from 1745 kg/ha to 1881 kg/ha).