水杨酸对鸭梨果实PG、PME和呼吸速率的影响

Effects of Salicylic Acid on PG,PME and Respiration in Ya-li Pears

在鸭梨果实生长发育前期,呈现一个水杨酸(SA)含量高峰,高峰过后,果实进入快速生长期。随着果实的成熟,SA含量下降。用SA喷施研究表明,不同处理时期、不同处理浓度对果实多聚半乳糖醛酸酶(PG)和果胶甲脂酶(PME)活性影响不同,其中于果实成熟前一个月(8月中下旬)喷施0.02mmol/LSA作用最强,7月上中旬各浓度处理对其作用不明显;圆片培养研究进一步表明0.02mmol/LSA可明显抑制PG和PME活性。喷施0.002～0.2mmol/LSA均明显抑制果实呼吸速率。

The effects of salicylic acid(SA)on ripening and senescence of Ya-li pears were studied by spraying SA.Results showed that the endogenous SA content peak appeared at the early stage of fruit development while after this peak fruit de-veloped quickly and SA content decreased sharply.The effects of SA on polygalacturonase(PG)and pectinmethylesterase(PME)in fruit were different with treated date and concentration.Whereas the activities of PG and PME were lower in the fruit sprayed with SA in August before harvest,while the effects of0.02mmol/L SA was significant.Furthermore,0.02mmol/L SA inhibited PG and PME activities in fruit disc;and the SA inhibited the fruit respiratory rate during storage.