为探索GA3处理对枇杷果实贮藏中呼吸及生理指标的影响,给生产提供理论依据.以生长在陕西安康的长崎早生枇杷为试验材料,采用不同浓度(10、50、100μmol/L)GA3溶液浸泡处理20min,然后贮藏于温度3℃±0.5℃,相对湿度65%—80%条件下,每隔7d测定果实呼吸强度、相对电导率、MDA含量以及PPO、POD、SOD、CAT和PAL等酶活性的变化.结果表明:GA3处理能够使果实在贮藏初期的SOD活性升高,极显著抑制贮藏中期PPO和PAL活性的升高.10μmol/L GA3处理可有效降低枇杷果实呼吸强度以及相对电导率和MDA含量.10μmol/L和50μmol/L GA3处理可极显著抑制贮藏后期果实CAT活性的下降.研究表明,采用10μmol/L GA3处理可使枇杷果实在贮藏中保持较好的生理状态.
In order to investigate the effects of GA3 treatment on physiological indices and to assist postharvest practice,the loquat fruit(Eriobotrya japonica Lindl.Chang Qi Zao Sheng)harvested from Ankang,Shaanxi Province were dipped with GA3 solutions at 10,50,100μmol/L,respectively,for 20min,and were stored at 3℃±0.5℃ and relative humidity(RH)65%—80%.Respiration rate,relative conductance,MDA content,activity of PPO,POD,SOD,CAT,and PAL of loquat were measured every seven days.Results showed that GA3 treatment enhanced SOD activity in the early stage of storage,and inhibited the activity of PPO and PAL extremely significantly in the middle stage of storage.Respiration rate,relative conductivity as well as MDA content of the fruit were effectively reduced with GA3 treatment at 10μmol/L.The decline of CAT activity was obviously retarded in the later stage with GA3 treatment at 10μmol/L and 50μmol/L.In conclusion,loquat fruit presents better physiological behavior during storage with GA3 treatment at 10μmol/L.