Abstract:

The effects of phloridzin and phloretin（typical phenolic acids in the soil of apple orchard） on the plant biomass，root activity，protective enzyme activities and the content of malondialdehyde（MDA）of one year Prunus persica grafted seedlings were studied under pot condition. The results showed that phloridzin could significantly damage the Prunus persica grafted seedlings，compared with the control，the fresh and dry weight reduced by 16.66% and 21.58%，respectively. The root activity reduced by 33.04%，and the activities of superoxide dismutase（SOD）and peroxidase（POD）reduced by 40.80% and 31.10%，while the content of MDA increased by 116.34%. Phloretin had little effect on the Prunus persica grafted seedlings. Potassium permanganateobviously alleviated the damage of phloridzin to Prunus persica grafted seedlings，significantly reduced the content of phloridzin in the apple orchard soil by 57.80%，improved the biomass，root activity，protective enzyme activities of the peach seedlings and reduced the content of MDA. In conclusion，phloridzin（0.343 mg · kg^-1）measured in old apple orchard soil could reduced the biomass of the peach seedlings，and moderate potassium permanganate could alleviate the damage of phloridzin on the peach seedlings.

Key words: Prunus persica, grafted seedling, soil, phenolic acid, phloridzin, protective enzyme, potassium permanganate