Abstract:

In order to clarify the effects of spraying different exogenous sugars on the leaf nutrient levels of grape after fruit harvest，Marselan grape was selected as the research object. Different concentration treatments of exogenous glucose（P1，P2，P3），exogenous sucrose（Z1，Z2，Z3），exogenous fructose（G1，G2）and exogenous sorbitol（S1，S2）were set up，with clear water as the control（CK）. Leaves were collected three times at 10 days，25 days and 32 days after fruit harvest. The contents of soluble sugar，soluble protein，total nitrogen and various mineral elements in leaves were determined. The results showed that at 10 days after fruit harvest，the soluble sugar，soluble protein，and total nitrogen content of leaves treated with Z2 significantly（p<0.05） increased by 76.16%，32.62%，and 42.06% compared with CK，respectively. At 10 days after fruit harvest，Ca content in Z2 and G2 treatments significantly increased by 64.91% and 62.30% compared with CK，respectively. At 32 days after fruit harvest，Zn content in Z2 and S2 treatments significantly increased by 8.64% and 7.30% compared with CK，respectively. At 32 days after fruit harvest，Fe content in Z2 and G2 treatments significantly increased by 12.40% and 12.06% compared with CK，respectively.In conclusion，Z2 treatment，which involved exogenous spraying of 0.17 mol·L^-1 sucrose，had the most significant effect on improving the leaf nutrition of Marselan grape.

Key words: Marselan grape, leaf nutrition, exogenous sugar, mineral element