Effect of time of sowing on oil content, erucic acid and glucosinolate contents in rapeseed ( Brassica napus L. cv. Marnoo)

The effect of time of sowing on the oil and meal quality of rapeseed (Brassica napus L. cv. Marnoo) was investigated at Werribee, Victoria, during 198 1 and 1982. In both years oil content declined with later sowing but the proportion of erucic acid in the oil was unaffected by sowing time. In contrast, later sowing increased the glucosinolate content of the seed meal, with July-September sowings exceeding the Canola standard. This increase was due primarily to the increased content of 2-hydroxybut-3- enyl glucosinolate (progoitrin).