Positional Differences of Fruits and Their Association with Fruit Abscission in'Cuiguan'Pear
TAN Zhihao
TAO Shutian
Abstract：To investigate the physiological differences among'Cuiguan'pear young fruits of different positions and their relationship with fruit abscission,this study compared the tissue structure,endogenous hormone levels,and reactive oxygen metabolism characteristics of young fruits at 13 days after full bloom,including abscising fruits.The results showed that low-position fruits had significantly higher individual fruit mass than high-position fruits.Abscising fruits exhibited a pronounced accumulation of abscisic acid(ABA),reaching 2.46 times the average level of normal fruits,while indole-3-acetic acid(IAA)remained at an intermediate level and gibberellic acid(GA3)showed no significant difference.In abscising fruits,hydrogen peroxide levels increased markedly,whereas catalase(CAT)activity was the lowest,indicating a decline in antioxidant capacity.Microscopic observations revealed the formation of a distinct abscission layer and lignified structure at the fruit pedicel.Collectively,these findings suggest that fruit abscission in'Cuiguan'pear was a result of multiple interacting factors,among which excessive ABA accumulation,changes in IAA levels,and reactive oxygen imbalance played key regulatory roles.This study elucidated the intrinsic link between fruit position and abscission in pear and provided a theoretical basis for the development and application of chemical thinning agents.
Keywords：Pearabscissionfruit positionendogenous hormonesreactive oxygen metabolism
Publication Date：2025-10-30
Online Publishing Date：2026-08-28(First online date of this platform, not the publication date of the document)
Pages：5( 32-36 )