Effect of H_2S on Assimilation of Nitrate Nitrogen in Wheat under Low Nitrogen Condition

The effects of low concentration of H2 S,produced by NaHS,on the photosynthesis and the absorption and assimilation of nitrate nitrogen in wheat seedlings(Triticum aestivumcv Yangmai 16)was studied under low-nitrogen(2mmol·L-1),medium-nitrogen(7.5mmol·L-1)and high-nitrogen(15mmol·L-1)culture conditions.The results showed that low concentration of H2 S could promote the photosynthesis and assimilation of nitrate nitrogen in wheat seedling,and the biomass of wheat seedlings under low-nitrogen was increased by 15,5%,as the content of soluble proteins,total nitrogen and chlorophylls in leaves were all up-regulated significantly.After treated by low concentrations of H2 S,the enzyme activities of NR(nitrate reductase),GS(glutamine synthetase)and GDH(glutamate dehydrogenase)were increased under medium-nitrogen and low-nitrogen conditions,especially which were significantly increased under low-nitrogen condition.While under high-nitrogen condition,the activities of NR and GS were reduced by 22%and 13%,compared to the control,respectively,and there was no difference in the activity of NADH-GDH.Above results indicated that low concentration of H2 S could promote photosynthesis and assimilation of nitrate nitrogen under low-nitrogen condition in wheat.