Mechanism for sucrose foliar application to reduce cadmium content in rice seedlings
To reduce the threat to human health caused by the accumulation of cadmium(Cd)in rice and its easy migration along the food chain.Here,we explored a potential mechanism for sucrose foliar application to regulate Cd uptake and transport in rice seedlings through hydroponic experiments.The results showed that after three consecutive sprays of 1.0 g·L-1 sucrose,the Cd content in the aboveground and root parts of seedlings significantly decreased by 26.7%and 22.0%,respectively.Concurrently,the contents of pyruvate,α-ketoglutarate,glutamic acid,and insoluble Cd,in the aboveground and root parts significantly increased by 11.8%and 23.6%,27.5%and 35.3%,165.3%and 40.3%,and 63.7%and 33.0%,respectively.Genes related to Cd uptake and translocation in the roots of the seedlings—OsNRAMP1,OsNRAMP5,and OsHMA2—were significantly down-regulated by 19.0%,78.8%and 16.3%,respectively.Furthermore,after sucrose spraying,SOD,CAT,and POD activities in the aboveground parts of the rice seedlings increased significantly by 66.9%,21.4%,and 23.6%,respectively.These results indicate that sucrose spraying promotes the glycolysis,pyruvate,and α-ketoglutarate in the aboveground and root parts of the seedlings and increases glutamic acid biosynthesis.Glutamate chelates with Cd in roots and shoots increasing recalcitrant Cd content in seedlings,reducing Cd transport from roots to aboveground parts,and alleviating Cd stress.
万方数据
维普
