The growth of mustard was increased significantly when treated with up to 80 kg N ha−1 (N80). Spraying with (2-chloroethyl) trimethylammoniumchloride (chlormequat chloride) increased seed yield and seed protein content. Spraying nitrogen fertilized plots with chlormequat chloride, increased leaf area, leaf area ratio, leaf area duration, number of siliquae plant−1, number of seeds siliqua−1 and length of siliqua. Reducing, non-reducing and total sugars in the leaves at 80 days after sowing were also affected significantly. Chlorophyll ‘a’, ‘b’ and total chlorophyll were little affected. The number of siliquae plant−1 was highly correlated with seed yield in both the seasons of experimentation. The correlation coefficient value (γ) was 0.586 in 1982/83 and 0.912 in 1983/84.
The total accumulation of nutrients, i.e. nitrogen, phosphorus and potassium in seed and straw was significantly affected by N80 × chlormequat chloride interaction.