A series of experiments to develop a suitable fertilizer use technology for Brassica cultivars under saline conditions, were carried out at the Research Farm, Department of Agronomy and Animal Nutrition. University of Agriculture, Faisalabad during 1999-2000 and 2000-2001.
Results obtained are summarized as below:- Plant sown at 15dSm-1 salinity level showed a significant reduction in plant height, number of primary branches plant-1 number of pods plant-1, number of seeds per pod, 1000-seed weight, seed yield, straw yield, biological yield per plant and seed oil concentration in both years. Foliar ionic composition determined 60 days after planting showed a significant increase in leaf Na+ and decrease in K+ content at a salinity level of 15 dSm-1 over control. As regards Brassica cultivars, generally, cv. DGL exhibited a significant increase in plant height, pods per plant, seed per pod, 1000-seed weight, higher seed yield, straw yield, biological yield per plant and seed oil concentration than cv. Con-II. Cultivar DGL showed low leaf Na+ but high K+ contents against the reverse in Con-II. Addition of 150 kg N ha-1 at 15 dSm-1 salinity level resulted in a significant increase in different growth and yield parameters of the two Brassica cultivars. Foliar ionic composition showed decrease in Na+ and a significant increase in K+ with the application of 150 N ha-1 over control in both years. Application of NP (125-100)or NPK (125-100-100 kg ha-1) in solution culture experiments increased plant height, pods per plant, number of seeds per pod, 1000-seed weight, seed yield, straw yield and biological yield per plant and also seed oil concentration significantly over other treatments. Foliar Na+ content decreased while K+ content increased significantly with the applications of NP and NPK over control. In pot culture experiments application of NP (125-100 kg ha-1), NK (125-100 kg ha-1) or NPK (125-100 kg ha-1) increased plant height, number of pods plant-1, seed pod-1, 1000-seed weight, seed yield and biological yield plant-1 significantly over rest of the treatments including control. A significant decrease in foliar Na+ and increase in foliar K+ contrnt was also recorded in treatments where NP, NK and NPK were applied. Under saline field conditions, split application of nitrogen fertilizers appeared to be the best technique.
Placement of fertilizer in rows below the seed proved better than side drilling and broadcast as it improved growth and yield contributing attributes to a significant level.