Effects of organic additives and elemental sulphur applied to soils on the growth and nutrient absorption of Brassica chinensis

Pot experiment was conducted to determine effects of rough amino acid, weathered coal,LTRP,L-PHE and elemental sulphur applied to soils on biomass, chlorophyll content,NO3--N,NRA and N,P,K,Fe absorption of Brassica chinensis. Results of the pot experiment showed that biomass of Brassica chinensis significantly increased with the application of weathered coal and combined application of L-TRP and L-PHE.It was found that application of weathered coal at rate of 20g/kg soil significantly increased chlorophyll content and N absorption of Brassica chinensis. When the elemental sulphur was applied at rate of 0.2 and 0.4 g/kg soil,NO3--N content in Brassica chinensis was decreased by 41.6% and 47.4%,respectively,compared with check plot.In the experiment condition,P,K,Fe absorption of Brassica chinensis was increased with the application of elemental sulphur,and deceased with the application of rough amino acid,weathered coal,and L-TRP,L-PHE or the combined application.Results also showed that application of the organic additives and elemental sulphur significantly increased the NRA of Brassica chinessis, but no significant correlation was found between NO3--N content and NRA in plants.The increase in NRA may be the result of coordinated effect of phytohormone or organic acid with NO3--N in the plant.