Better growth and yield performance of lentil under different level of phosphorus,sulphur and zinc in sub-humid Southern plain of Rajasthan

A field experiment was conducted during the winter (rabi) season of 2020–21 and 2021–22 at Instructional Farm, Rajasthan College of Agriculture, Udaipur (Rajasthan) to assess the impact of different levels of phosphorus, sulphur and zinc on growth parameters and yield of lentil. The experiment was laid out in randomized complete block design (RCBD) with three replications and 18 treatment combinations. Phosphorus factor comprised of 3 levels, viz. 30, 40 and 50 kg P2 O5 /ha along with sulphur that comprised of 3 levels, viz. 15, 20 and 25 kg/ha; and zinc factor with 2 levels, viz. control and 0.5 % ZnSO4 foliar spray at 55 Days after sowing (DAS). Results revealed that the higher plant height, dry matter accumulation (DMA) and primary branches/plant were recorded with application of 40 kg P2 O5 /ha in combination of 25 kg/ha sulphur and foliar spray of 0.5% ZnSO4 at 55 DAS. The dry matter accumulation (0.838**) and plant height (0.871**) had a significant and positive correlation with the seed yield. The crop growth rate (CGR) enlaced by 10.49% and root-shoot ratio by 7.21% with application of 40 kg P2 O5 /ha over 30 kg P2 O5 /ha. Similarly, the CGR and root-shoot ratio of lentil were significantly enhanced by 11.95 and 5.19%, respectively with 25 kg/ha over 15 kg/ha sulphur application at 60-90 DAS. Likewise, the significantly increased CGR by 5.09% and root-shoot ratio by 3.72% with application of 0.5% ZnSO4 as foliar spray over control. Moreover, the effective nodules increased by 22.68% and fresh and dry weight by 20.9 and 8.0% respectively with 50 kg P2 O5 /ha during both the years. The effective nodules and fresh and dry weight of nodules/ plant increased by 13.59, 12.68 and 6.52% respectively with 25 kg/ha over 15 kg/ha suphur application while it was increased by. 6.71%, the by 6.39 and 4.08% respectively with 0.5% foliar spray of ZnSO4 over control. Furthermore, significantly higher seed, haulm and biological yields increased by 9.34, 12.90 and 11.75%, respectively with 40 kg P2 O5 /ha followed by 50 kg P2 O5 /ha over 30 kg P2 O5 /ha. Similarly, the application of 25 kg/ha sulphur significantly enhanced seed yield, haulm and biological yields of lentil but it has no significant effect on the harvest index. The foliar spray of 0.5% ZnSO4 increased the seed yield by 4.71 per cent, haulm yield by 7.30 per cent and biological yield by 6.45% over control. The plant growth parameters, yield attributes and yield of lentil were significantly enhanced with the application of P2O5 (40 kg/ha) and sulphur (25 kg/ha) along with ZnSO4 (0.5%) as foliar spray at 55 days after sowing as compared to other treatment combinations. These treatment combinations could be adopted to achieve better growth performances and bridging yield gap of lentil in sub-humid agro ecologies.