USE OF PLANT ANALYSIS TO PREDICT SULFUR DEFICIENCY IN RAPESEED ( Brassica napus and B . campestris )

Abstract

The sulfur status of rapeseed (Brassica napus and Brassica campestris) plants grown in field studies was assessed using a variety of plant indices; percent sulfur, percent hydriodic acid reducible sulfur (HI-S in plant dry matter), HI-S:total S ratio, and total N:total S ratios. Of these, HI-S:total S determined at the rosette growth stage was the most accurate and consistent index of seed yield. A growth chamber study indicated that the HI-S:total S ratio would not be affected by nitrogen fertilizer application at normal field rates. Key words: Sulfur, deficiency, rapeseed (Brassica spp.), plant analysis