Mechanism of Herbivore-induced Plant Volatilesin Host-plant Selection by Herbivorous Insects

Abstract

Plant volatiles play a crucial role in host selection of insects. Insects can detect them from a longer distance and then make host orientation, oviposition, aggregation and pollination. The plant volatiles mainly include two categories; one emits during plant growth process while the other is produced and emitted after insect herbivory (herbivore-induced plant volatiles, HIPVs). Moreover, some volatiles have an attractive or repellent effect on the herbivorous insects while others show mutualism, attraction and orientation to the carnivores. However, studies on HIPVs mainly focus on how to attract carnivores, and rarely on the effect on insects themselves. Numerous researches stumble with the phenomenon that different pests often damage the same plant at the same time, but this phenomenon does not lead to a stronger attack by carnivores sometimes; on the contrary, it leads to attraction or repellency to interspecific and intraspecific herbivorous insects, which influences the damage degree of host plants. For this reason, the paper focuses on giving a comprehensive and in-depth summary of the behaviors caused by HIPVs, especially the attraction or repellency to interspecific and intraspecific herbivorous insects. The paper further derives new theoretical basis of making a thorough study of HIPV mechanisms and explicating how insects make a host selection. In short, the discussion is aimed to enrich the theoretical basis and scientific foundation for IPM of pests by studies of HIPVs.