Effect of sulphur nutrition on productivity, nutrient uptake and economics of pearl millet (Pennisetum glaucum)-Indian mustard (Brassica juncea) cropping system

A field experiment was conducted in two consecutive kharif and rabi seasons of 2010-11 and 2011-12 at Panwari village, Agra on a sulphur deficient soil to assess the direct effect of sulphur on productivity of pearl millet (Pennisetum glaucum (L.) R. Br. emend Stuntz) and residual effect on succeeding Indian mustard [Brassica juncea (L) Czernj and Coss] and uptake of nutrients by the crops and soil fertility under pearl millet -mustard crop sequence. The experiment was laid out in randomized block design with five levels of sulphur (0, 15, 30, 45 and 60 kg/ha) and four replications. Results revealed that an application of 30 kg S/ha to pearl millet recorded significantly highest plant height (226.5 cm), ear head length (30.1 cm), ear head diameter (10.90 cm), 1000 grains weight (11.08 g) and grain weight/ear head (34.12 g). Sulphur fertilization in preceding pearl millet crop at 45 kg/ha was found to be best for growth and yield attributes of mustard. Pearl millet crop responded significantly up to 30 kg S/ha by producing 3.43 tonnes grain and 8.34 tonnes stover/ha. The residual effect in mustard crop was significant at 45 kg S/ha and grain and straw increments were to the extent of 28.2 and 24.9% over control, respectively. The content and yield of protein in both the crops increased significantly with sulphur up to 45 kg/ha, whereas the content and yield of oil in mustard seeds increased up to 60 kg S/ha. The uptake of S by both the crops increased significantly with increasing levels of sulphur. A phenomenal increase in N, P and K except of Zn was recorded in pearl millet and mustard crop due to increasing levels of sulphur up to 30 and 60 kg S/ha, respectively. The amount of available S was reduced in the control plot but at higher levels of S, sufficient amount of available S remained in the post harvest soil. The values of efficiency indices decreased with the increase in levels of sulphur. Net returns ((sic) 54 961/ha) and benefit: cost ratio (3.82) were the highest with 45 kg S/ha in the pearl millet -mustard crop sequence.