氨基糖苷类抗生素在植物体内吸收、转运及机制研究

Pesticide which can moves through phloem down to root shows excellent properties on control plant diseases and insect in the roots and in vascular bundle. Phloem transported pesticides, avoiding the influence of soil, reducing the use of pesticide, improve the control effect significantly. But so far, the number of fungicide is quite limited, although in recent years there have been reports of the advent of a new fungicide. Two-way transmission of pesticide research and development is still a very important research area today. Bases on aminoglycoside antibiotics can be actively absorbed by bacteria and animal cells, kasugamycin that sprayed on leaf of tobacco and rice could translocated to the bottom site, tobacco leaf disc can actively uptake kasugamycin, Uptake, translocation and distribution of aminoglycoside antibiotics validamycin, gentamycin and kasugamycin by in tobacco, wheat and ricinus will be studyed with the mainly technology of laser confocal microscopy, fluorescence tracer, preliminary proven its regularity and mechanism, providing theoretical basis for research and development of phloem transported pesticides.

能通过韧皮部向下移动的的农药，可以通过叶面用药来防治根部和维管束病虫害，从而避免土壤因子对药剂的影响，可以大大地降低农药的使用成本，提高防治效果。但到目前为止，能通过韧皮部向下输导的杀菌剂的数量相当有限。氨基糖苷类抗生素能被细菌、动物细胞主动吸收，春雷霉素可被烟草叶片主动吸收，通过烟草、水稻叶面向下输导。基于此，本研究以井冈霉素、庆大霉素、春雷霉素等氨基糖苷类农用抗生素为对象，利用激光共聚焦显微技术、荧光示踪技术，探究其在烟草、小麦、蓖麻细植株的吸收、分布、转运规律及机制，为研发经韧皮部向下输导的杀菌剂提供理论基础。

研究按原计划并完成研究目标。利用HPLC-MS技术研究了氨基糖苷类抗生素在蓖麻、水稻、玉米、烟草、番茄和茄子的组吸收与分布。结果表明，叶部施药后，氨基糖苷类抗生素能在植物体全株分布，能向根部输导。通过研究浓度梯度、温度、pH、底物、能量抑制剂对植物吸收氨基糖苷类抗生素的影响，明确了植物吸收氨基糖苷类抗生素是由转运蛋白介导下的主动吸收。用HPLC-MS/MS和荧光示踪法，阐明了春雷霉素主要是通过木质部和韧皮部进行双向输导。用转录组技术分析筛选出参与水稻响应春雷霉素和井冈霉素在组织细胞跨膜转运的关键基因8个，分别是编码单糖转运蛋白和二糖转转运蛋白以及ABC转运蛋白基因，说明药剂进入水稻组织与水稻中的运载体有密切关系。研究结果对于研发根部导向的农药具有重要的指导意义。