Evapo-transpiration, water-use efficiency, moisture use and yield of Indian mustard (Brassica juncea) under varying levels of irrigation and nutrient management in Vertisol

Abstract

A field study was conducted during 1998-99 and 1999-2000 on a Vertisol, to assess the effects of irrigation levels, and combination of NPK and farmyard manure on moisture use, evapo-transpiration. water-use efficiency and yield of Indian mustard [Brassica juncea (L.) Czernj. & Cosson]. The moisture extraction was maximum (43.9%) from the upper 0-30 cm soil depth irrespective of irrigation and nutrient treatments and increased with the increase in number of irrigations applied. The evapo.transpiration of the crop increased with increase in level of irrigation as the crop season advanced and reached its peak (42.9 mm and 48.5 mm in 1 and 2 irrigations respectively) between 75 and 90 days after sowing. Under no irrigation, the evapo-transpiration reached its peak (21.1 mm) belween 60 and 7S days after sowing. Seed yield increased significantly with the increase in irrigation number, but the water-use efficiency was highest (7.1 and 6.8 kg/ha-mm in the first and second year respectively) at no irrigation, followed by 1 and 2 irrigation treatments respectively. The application of recommended dose of NPK (60, 13.1 and 16.6 kg/ha) + farmyard manure@10tonneS/ha (applied to the previous rainyseason crop) resulted in significantly higher seed yield (16.1 and 28.1 % over recommended dose of NPK and 91.7 and· 95.7% over the control in the first and second year respectively) and improved the water-use efficiency compared With recommended dose of NPK and control treatments.