Abstract:

Potted seedlings of 3-year-old red-leaf peach 'tsukuba-6’ were used to study pigments content, soluble sugar and starch content, activity of phenylalanine ammonia-lyase (PAL), and net photosynthetic rate in leaves with the foliar spray of KH₂PO₄ and sucrose solution during the regreening of red-leaf in early summer. The results showed that, both KH₂PO₄ and sucrose solution promoted accumulation of anthocyanin (Ant) of red-leaf peach remarkably, increased the ratio of Ant, chlorophyll (Ant/Chl), the soluble sugar, starch content and activity of PAL in leaves. KH₂PO₄ also improved net photosynthetic rate(P_n) of red-leaf peach. Furthermore, of all the treatments, 0.3% KH₂PO₄ solution or 0.5% sucrose solution was best in promoting leaf-colored. The foliar spray of KH₂PO₄ or sucrose solution was an economic and easy method to alleviate regreening of red-leaf peach in summer for urban greening management.

Key words: red-leaf peach, KH₂PO₄, sucrose, anthocyanin, photosynthetic pigments, net photosynthetic rate