膜醭毕赤酵母和壳聚糖复合处理对柑橘果实炭疽病的诱导抗病性

以‘锦橙447’为试材，研究了膜醭毕赤酵母和壳聚糖复合处理对柑橘果实采后炭疽病的防治效果，以及在接种炭疽菌的情况下诱导柑橘果实抗病性的机制。结果表明：1×108 cells/mL的膜醭毕赤酵母和0.1 g/L的壳聚糖单独处理均能够有效抑制柑橘果实炭疽病的发病率，而复合处理的防治效果更好。膜醭毕赤酵母和壳聚糖复合处理能够增加NO、水杨酸、H2O2等信号物质的含量；提高苯丙烷代谢中间产物阿魏酸、对香豆酸、绿原酸的含量，相关防御酶如苯丙氨酸解氨酶、肉桂酸-4-羟基化酶、4-香豆酸:辅酶A连接酶、过氧化物酶、多酚氧化酶的活力；以及病程相关蛋白如几丁质酶和β-1,3葡聚糖酶活力。该研究结果表明，膜醭毕赤酵母与壳聚糖复合处理可通过增强柑橘的抗病性来提高柑橘炭疽病的防治效果。

Pichia membranaefaciens Combined with Chitosan Treatment Induces Resistance to Anthracnose in Citrus Fruit

This study was undertaken in order to investigate the combined effect of Pichia membranaefaciens and chitosan on controlling anthracnose and inducing anthracnose resistance in citrus fruit (Citrus sinensis L. Osbeck. cv. Jincheng 447) inoculated with Colletotrichum gloeosporioides. The results showed that the application of P. membranaefaciens (1 × 108 cells/mL) or chitosan (0.1 g/L) were effective in inhibiting anthracnose but inferior to their combination. The combined treatment increased the contents of some signal substances including NO, salicylic acid and H2O2 as well as the contents of intermediate metabolites of phenylpropane (ferulic acid, p-coumaric acid and chlorogenic acid), and induced higher activities of defense-related enzymes including phenylalanine ammonia-lyase, cinnamate-4-hydroxylase, 4-coumarate:coenzyme A ligase, peroxidase and polyphenoloxidase and higher activities of pathogenesis-related proteins (PR-proteins) such as chintinase and β-1,3-glucanse. In conclusion, P. membranaefaciens combined with chitosan induces anthracnose resistance in citrus fruit.