Studies on uptake and translocation of sulphur in oil seed rape plant using 35S tracer technique

The experiments were conducted to investigate the uptake and translocation of 35S in oil seed rape at different stages. The results showed that uptake of sulphur from soil by rape plant were 23.59%, 31.65% and 49.13% of sulphur applied at transplanting, bolting and flowering stage, respectively. About 40% of 35S taken from soil was located in seeds for transplanting and flowering stage applying. About 20% of sulphur applied on top four leaves at various stages of growth was remained in labelled leaves and 21%∼23% was transported to pods with majority in branch pods. 40%∼60% of sulphur which was applied on surface of pods at lower stem at different time after flowering was remained in shell of labelled pods and 13%∼16.8% of that was transferred into seeds of labelled pods. Recoveries of labelled sulphur applied on pods from seeds of pods at branches were less than 10%. The transportation of 35S from labelled sites to seeds of labelled pods and unlabelled pods was declined sharply as labelling was carried out at 6 weeks after flowering