柑橘黄龙病是毁灭性的细菌病害，其灾变机制仍未厘清。它的媒介昆虫－柑橘木虱的寄主仅限于芸香科植物，目前在研究和防治上也专注于此。我们发现木虱成虫可选择栖息在一些非芸香科的杂草上，虽不能完成世代但可长期存活，并在杂草上检测出黄龙病菌，显示这些杂草可能有利于木虱传播黄龙病。本项目拟在前期工作基础上，选择橘园常见杂草龙葵、菟丝子和藿香蓟，以柑橘为对照，通过研究：(1) 杂草对木虱个体存活和种群发展的影响；（2）病菌传入、传出杂草的能力和方式；（3）杂草对木虱体内病菌存活与增殖的影响；(4) 病菌对木虱选择和适应杂草的影响；（5）杂草上木虱相关酶的活性变化；（6）与杂草影响木虱和病菌生存、增殖相关的植物化学信息、营养或限制因子，探索杂草在柑橘木虱传播黄龙病中的作用与机制，为今后深入研究其分子机理、全面厘清黄龙病的传播途径和灾变机制提供依据，也为细菌-害虫-植物互作机理的研究提供参考。

Citrus huanglongbing (HLB) is a destructive bacterial disease, which is spread by the vector-Asian citrus psyllid (ACP) effectively. Its catastrophe mechanism is still unclear. Though the host range of ACP is strict, some non-host weeds let ACP adult feed on and long - term survive, and HLB bacterium was tested out. It showed that weed had certain effect to ACP and HLB spread. In our project, 3 weeds would be chosen to study on effect of them on ACP and HLB spread, with the host plant as the control. It include: (1) Effect of weed on ACP survival time, fertility and population development, (2) Way and ability of HLB spread from or to weed, (3) Effect of weed on HLB bacterium survival and multiplication, (4) Effect of HLB bacterium on choice and adaption of ACP to weed, (5) Ativity change of digestive and resistance enzyme of ACP on weed, (6) Weed secondary compounds related to survival and multiplication of ACP and HLB bacterium. From these results, the effect of the weeds on ACP and HLB spread and its mechanism would be analyzed, which would be help to probed its molecular mechanism, clarify the catastrophe mechanism and transmission route of HLB and provide references to research on the interaction mechanism between pathogenic bacteria, insect vector and plant.