Chen Chen, Hu Wenzhong, Zhang Ruidong, Jiang Aili
1 College of Life Science, Dalian Minzu University, Dalian, China.
2 Dayaowan Entry-Exit Inspection and Quarantine Bureau, Dalian, China.
Food Sci Technol Int. 2018 Mar;24(2):161-171. doi: 10.1177/1082013217736203. Epub 2017 Oct 30.
In this study, the effects of oligochitosan treatment on controlling postharvest diseases in Dongxue peach ( Prunus Persica L. Batsch, cv Dongxuemi) were examined and the possible underlying mechanisms were discussed. Results showed that the disease incidence and lesion area in peach fruit inoculated with Monilinia fructicola and Penicillium expansum were all remarkably reduced by oligochitosan treatment. Oligochitosan treatment inhibited spore germination and mycelial growth of the two fungi in vitro. Oligochitosan treatment also induced upregulation of the salicylic acid signalling pathway-related genes (NPR1, PR1 and phenylalanine ammonia lyase) and enhanced the levels of total phenolics, flavonoids and lignin in peach. Meanwhile, enzymatic activities of superoxide dismutase, catalase, polyphenoloxidase, ascorbate peroxidase and phenylalanine ammonia lyase also increased. These findings suggest that the effects of oligochitosan on the disease control of peach fruit may be associated with its direct antimicrobial effects as well as increasing antioxidant, phenylpropanoid metabolism and accumulating antifungal compounds by activating the salicylic acid-dependent pathway.
本研究考察了低聚壳聚糖处理对东学桃（Prunus Persica L. Batsch，品种东雪蜜）采后病害的防治效果，并探讨了其可能的潜在机制。结果表明，用低聚壳聚糖处理接种了褐腐病菌和扩展青霉的桃果实，其发病率和病斑面积均显著降低。低聚壳聚糖处理在体外抑制了这两种真菌的孢子萌发和菌丝生长。低聚壳聚糖处理还诱导了水杨酸信号通路相关基因（NPR1、PR1和苯丙氨酸解氨酶）的上调，并提高了桃中总酚、类黄酮和木质素的含量。同时，超氧化物歧化酶、过氧化氢酶、多酚氧化酶、抗坏血酸过氧化物酶和苯丙氨酸解氨酶的酶活性也有所增加。这些结果表明，低聚壳聚糖对桃果实病害的防治作用可能与其直接的抗菌作用以及通过激活水杨酸依赖途径增加抗氧化、苯丙烷代谢和积累抗真菌化合物有关。
