A pot experiment was conducted on a Mollisol from Nainital tarai to investigate the effect of selenium and sulphur application on dry matter yield, their content and ratios in sunflower plant parts. All possible combinations of four levels of selenium (0, 0.5, 1.0 and 2.0ppm) with three levels of sulphur (0, 40 and 80 ppm) were applied. The degree of chlorosis, cupping and stunting (plant injury) progressively increased, whereas dry matter yield and S: Se ratio decreased at budding stage with successive increase in selenium levels. A gradual improvement in plant health was observed with successive increase in sulphur levels. The maximum dry matter yield was observed with 1500: 1 ratio of S to Se in shoot at budding stage.
Sunflower, selenium toxicity, sulphur nutrition, selenium—sulphur relationship
