套袋黄冠梨黑点病与钙素营养和果实衰老的关系

为探明套袋黄冠梨果实黑点病发病原因,从采后生理、矿质营养水平、酚类物质酶促褐变和果实衰老等方面对套袋黄冠梨果实黑点病进行了研究。结果表明:套袋果呼吸强度显著高于不套袋果;套袋果Ca含量仅为不套袋果的49%-63%,果皮钙素含量未套袋果>套袋健康果>套袋病果,套袋病果与不套袋果果皮N/Ca比值分别为9.8和6.1,K/Ca比值分别为17.6和8.8;果皮和果心酚类物质含量及多酚氧化酶活性(PPO)呈套袋病果>套袋健康果>未套袋果的趋势;套袋病果果皮丙二醛(MDA)含量及电导率显著高于未套袋果;果皮钙素含量与其PPO活性、多酚及丙二醛含量、电导率呈高度负相关。初步分析黄冠梨果实黑点病病因为缺钙性生理衰老。

Study on the relationship between the black spot disease of bagged Huangguan pear fruit and the fruit calcium content and senescence

Experiment was conducted with the bagged Huangguan pear fruit infected with black spot disease in order to study the reasons of the occurrence of this disease and its relationship with fruit calcium content and fruit senescence. The bagged fruit quality, respiration, mineral nutrient, flesh browning and senescence were studied. The results showed that the respiration rate of the bagged fruit was significantly higher than that of control. The calcium content of bagged fruit was just 49%-63% of the control. The ratio of N/Ca of bagged fruit and control was 9.8 and 6.1, and K/Ca was 17.6 and 8.8 respectively. The calcium content in the fruit skin was control >bagged disease-free fruits >bagged diseased fruits. The contents of polyphenol and PPO activity of the fruit skin and the core were bagged diseased fruits >bagged disease-free fruits >control. MDA content and conductance of the skin of bagged diseased fruits were significantly higher than those of control. There was a high negative correlation between the calcium content of the fruit skin and PPO activity, polyphenol content, MDA content and conductance. Preliminary analysis showed that the occurrence of the black spot disease was related to the physiological senescence induced by calcium scarcity.