Optimizing maize productivity: Impact of sowing dates on growth and yield parameters of diverse genotypes in Karnataka's southern dry zone

This study examined the impact of various sowing windows on growth parameters and yield attributes of maize genotypes in the southern dry zone of Karnataka, India. Field experiments were conducted during the Kharif seasons of 2021 and 2022 at Haradanahally village, Chamarajanagara district, using a Randomized Complete Block Design (RCBD) with three replications. Two maize hybrids MAH 14-5 and Hema were evaluated across four sowing windows (1st week of June 3rd week of June 1st week of July and 3rd week of July) under rainfed conditions. Plant growth parameters (plant height, number of leaves and leaf area) were measured at 30th, 60th and 90th days after sowing (DAS) and yield attributes (cob length, kernels per cob, cob girth, rows per cob, test weight, grain yield and stover yield) were recorded at harvest. Results indicated that the MAH 14-5 hybrid, sown during the 1st week of July (H1D3), consistently performed better across both years in terms of plant height (218.23 cm), number of leaves (16.61), leaf area (8318 cm²), cob length (17.03 cm), kernels per cob (580.64), test weight (34.46 g), grain yield (6980 kg/ha) and stover yield (9155 kg/ha). In contrast, the Hema hybrid, sown during the 1st week of June (H2D1), recorded the lowest performance across all parameters. Statistical analysis (ANOVA) revealed significant differences (p < 0.05) among the treatments and post hoc tests confirmed that optimal performance was achieved through the combination of MAH 14-5 and 1st week of July sowing. These findings suggest that proper synchronization between sowing time and hybrid selection can enhance resource use efficiency and maize productivity under rainfed conditions in Karnataka’s southern dry zone. This research provides site-specific recommendations to help farmers make informed decisions on the sowing time of different maize hybrids under similar agroclimatic conditions.