中国月季感染白粉菌对甜菜夜蛾取食行为的影响及原因初探

Effects of rose infected by powdery midew on feeding behaviour of beet armyworm and its mechanism

以月季白粉菌-中国月季植株-甜菜夜蛾三元系统为例,研究了月季白粉菌侵染中国月季对甜菜夜蛾的影响及其空间效应,并对产生影响的原因进行初探。结果表明,白粉菌侵染中国月季使甜菜夜蛾幼虫取食量下降(从989.1 mm2下降到198.5 mm2),对该虫产生了不利影响,这种影响存在明显的空间效应,并随着感病程度的增加取食量下降。这一变化规律与植物感病后水分含量变化(80.23%下降到60.59%)规律相符,说明白粉菌侵染植株导致植株水分含量变化是甜菜夜蛾幼虫取食量下降的重要原因。研究结果为病虫互作关系及其互作机理的研究奠定了基础。

It is well-known that the interactions between phytopathogenic fungi and herbivory insects on their shared host plants exist commonly. But the interaction was studied mainly under macro ecological methods in most of researches. Thus, they remain unclear whether the spacial effect exists in the interaction between fungi and insects and how to interact each other. In the present study, the inhibitory effects of rose infected by powdery mildew infection on beet armyworm, the spaeial effects, and the mechanisms of inhibition were studied. The results showed that the infection of rose plants by rose powdery mildew caused the decrease of amounts of leaf area consumed by larvae of beet armyworm （ from 989.1 mm2 to 198.5 mm2 ） , demonstrating a significant inhibitory effect on insects. The spacial effects were found in the inhibition and the amounts of leaf area consumed gradually decreased with the increase of infection level. The changing trends of inhibitions were the same as the trends of changes of water content in rose leaf tissues caused by the infection （ from 80.23% in healthy rose leaves to 60.59% in infected ones ） . Therefore, the results indicated that the decrease of water content in rose leaves caused by the infection was mainly responsible for the inhibition of larvae. The results in the present study are very helpful to understand the interactions between fungi and insects and its mechanisms.