Current Journal of Applied Science and Technology

Soil water and nitrogen (N) are the two most important factors in wheat for obtaining higher grain yield. In this context, a field trial was conducted at the research farm (25â°38´ N, 88â°41´ E and 38.20 m above sea level) of the Wheat Research Centre (WRC), Bangladesh to identify the timing of first irrigation (FI_timing) and its combination with a split application of N (N_SA) for improved yield of wheat. The treatments applied were two levels of N (75 and 100 kg ha⁻¹) and different amounts of N in splits with different application times of FI to verify the FI_timing in light soil and to minimize N use by rescheduling the FI. Existing wheat variety ‘Prodip’ was used as the experimental material. The interaction between FI_timing and N_SA on yield and yield-related components of wheat, except for 1000-grain weight, did not vary significantly. However, higher grain yield (3.39 t ha⁻¹) was obtained when the crop was irrigated at 15 days after sowing (DAS) than when irrigated latter (20, 25 and 30 DAS). On average, higher grain yield (3.58 t ha⁻¹) was obtained from 100 kg N ha⁻¹ when it was applied half as basal and half as one top dressing than 75 kg N ha⁻¹ when applied half as basal and half as one top dressing. Large grains were obtained when the FI was applied at 25 DAS in all N treatments except for 75 kg N ha⁻¹ when applied half as basal at the time of final land preparation and half as top dressing, on 30 DAS in half N as basal at both levels of N and at 15 DAS when 100 kg N ha⁻¹ was applied half as basal and half as top dressing. So, it is evident that the amount and split application of N with first irrigation are the most important factors determining higher grain yield and yield-related components of wheat in light soil of Bangladesh. According to our research findings, 100 kg N ha⁻¹ is recommended, 1/2 as basal and 1/2 as top dressing at the time of FI at 15 or 20 DAS.