低分子量壳聚糖对植物病原菌的抑制作用研究

目的]探索壳聚糖对植物病原菌的抑制作用与其分子量的关系。方法]通过测定最小抑制浓度和抑制圈，研究不同分子量的低分子量壳聚糖对稻胡麻叶斑病菌等13个植物原病菌的抑制作用。结果]对多数植物病原菌来说，可溶性的低分子量壳聚糖分子量在662-5492范围内，随分子量的增加，其抑菌能力增强，抑菌效果更明显，最小杀菌浓度减小，杀菌能力增强。其中以聚合度在10～34，分子量在1628～5492的低分子量壳聚糖抑菌效果最好，对野油菜黄单孢-8004菌、青枯雷尔氏菌GM11000菌株和辣椒斑点病菌的抑菌效果都很好。结论]该研究为植物病原菌抑制剂的开发提供了依据。

Study on Inhibiting Effect of Low Molecular Weight Chitosans on Plant Pathogenic Bacteria

Objective]The aim was to explore the relationship between the inhibiting effect of chitosans on plant pathogenic bacteria and its molecular weight.Method] The inhibiting effect of low molecular weight chitosans(LMWC) with different molecular weights on 13 plant pathogenic bacteria such as Helminthosporium oryzae were studied by detecting the minimum inhibitory concn.and inhibitory circle.Result] To most plant pathogenic bacteria,the antibacterial ability of the soluble LMWC was strengthened,the inhibiting effect was more obvious,the minimum inhibitory concn.was decreased and the sterilization ability was strengthened with the increment of the molecular weight when the molecular weight of LMWC was in the range of 662-5 492.Among them,the inhibiting effect of LMWC with the polymerization degree of 10-34 and molecular weight of 1 628-5 492 was best,which had better inhibiting effect on Xanthomonas campestris-8004,Ralstonia solanacearum GMI1000 and Stemphylium lycopersici.Conclusion] The research provided the basis for the development for plant pathogenic bacteria inhibitor.