Abstract:

The aim was to study the effects of Nitric oxide (NO) sodium nitropprusside (SNP, an exogenous nitric oxide donor) on growth and cadmium accumulation in Sedum alfredii Hance under Cd stress. Three concentrations of Cd (Cd0, Cd10, Cd100) and five levels of exogenous NO (SNP) were carried out. The results showed that exogenous NO significantly affected the biomass (dry) of Sedum alfredii Hance. With the increment of SNP concentration, biomass of root in Sedum alfredii Hance were increased by 8.4%-14.5% under Cd0 and Cd100 treatments, but decreased under Cd100 treatments (except SNP0.05 treatment). Under Cd100 level, biomass of stem, leaf and total plant were increased by8.4%-14.5%, 6.9%-22.0% and 12.6%-18.7% (except SNP0.1 treatments), respectively. With increscent of SNP level, Cd contents and amounts of Cd accumulated in different part and total plant of Sedum alfredii Hance were significantly increased under Cd stress. With the increase of Cd level, Cd contents and amounts of Cd accumulated also significantly increased at same SNP level. With the increment of SNP concentration, Cd uptake efficiency of Sedum alfredii Hance were increased by 2.9%-79.8% under Cd10 treatments, and Cd translocation efficiency were increased by 0.5%-81.9% and 16.4%-32.0% under two Cd levels, respectively. NO could increase the growth and cadmium accumulation of Sedum alfredii Hance and the effect was related to the concentration of NO and Cd levels.