热激处理对冷藏枇杷果实冷害的生理作用

Effects of heat shock treatment on chilling injury and physiological responses of Eriobotrya japonica fruit during cold storage

枇杷(EriobotryajaponicaLindl.)果实采后经48～52℃、10min的热激处理,然后2～5℃贮藏,通过对贮藏期间果实冷害级别、呼吸速率、过氧化物酶、过氧化氢酶、苯丙氨酸解氨酶活性和质膜相对透性变化的分析,研究贮前热激处理对冷藏枇杷果实冷害的生理作用。结果表明,2～5℃低温可诱导枇杷果实呼吸速率和苯丙氨酸解氨酶活性异常升高,果实冷害程度与苯丙氨酸解氨酶活性之间呈正相关,相关系数r=0.926。热激处理能降低冷藏条件下(2～5℃)枇杷果实呼吸速率的异常升高,减轻由于低温胁迫造成的果肉细胞膜损伤,提高枇杷果实的过氧化物酶和过氧化氢酶活性,降低苯丙氨酸解氨酶的活性。贮前热激处理有推迟和减轻枇杷果实冷害症状发生、降低果肉低温劣变的作用。贮前热激处理结合低温冷藏是延长枇杷果实贮藏寿命的有效措施之一。

The Eriobotrya japonica Lindl. fruit was treated with heat shock of 48-52℃ for 10 min, and then stored at 2-5℃. Physiological effects of this heat shock treatment on chilling injury of the fruit were studied by analyzing periodically the changes in the degree of chilling injury, respiratory rate, peroxidase activity, catalase activity, phenylalanine ammonialyase activity and plasmalemma relative permeability of the fruit during cold storage. The results showed that the respiratory rate and the phenylalanine ammonialyase activity of the fruit sharply increased under low temperature stress condition (2-5℃). The degree of chilling injury of fruit was significantly positive correlation with the activity of the phenylalanine ammonialyase (r=0.926 ). The heat shock treatment could lower the respiration rising, lighten the chilling injury of membrane, enhance the peroxidase activity and catalase activity and reduce the phenylalanine ammonialyase activity of the fruit stored at low-temperature (2-5℃). The heat shock treatment can enhance resistance to chilling injury of the fruit, postpone the symptom of chilling injury appearing and lighten the degree of chilling injury. The heat shock treatment (48-52℃ for 10 min.) before cold storage (2-5℃) is a effective method of prolonging the shelf life of E. japonica fruit.