Effects of Sulphur on Seed Yield , Oil , Protein and Glucosinolates of Canola Cultivars

Abstract

Sulfur is the fourth major nutrient in crop production. Most crops require as much sulfur as phosphorus. Rape cultivars have recently been introduced in Pakistan agriculture and so information related to sulfur effects on their seed yield and seed composition are scanty. A two-year study (2003-04 and 2004-05) was conducted to document the effects of sulfur application on the seed yield, oil, protein and glucosinolates of rape cultivars. Treatments comprised: two rape cultivars (Shiralee and Con-11) and four sulfur levels (0 (control), 15, 20 and 25 kg/ha). The cultivars exhibited statistically significant variations for protein but non-significant differences for seed yield, oil and glucosinolates. Similarly, sulfur effects on seed yield, oil, protein and glucosinolates were neither significant nor consistent. However, the interactive effects were observed to be significant. Seed yield, protein and glucosinolates increased during the second year compared to those observed during the first year, whereas oil content exhibited an opposite trend and decreased during the second year compared to the first year. An inverse relationship was observed between oil and protein during both years of experiments. However, glucosinolates exhibited a linear relationship with the sulfur level but did not show any significant relationship with seed yield.