Primary Study On VOCs Released By Michelia Skinneriana And Volatile Signaling In Plant-Plant Interaction

In this paper,Michelia skinneriana plants were labled into three types:healthy, near-contrastive and insect-damaged.This paper mainly included two parts:the analyse of VOCs released by the above-mentioned three types of plants and volatile signaling interaction in Michelia skinneriana population.The results showed all the VOCs released by the three types were complicated compounds including various components.VOCs released by healthy Michelia skinneriana plants(13:00-15:00) contained 73 components,in those there were 38 components which hold a respective relative content above 0.05%,and their total content was 82.14%.Three components,that were 1-Propanol,2-methyl and Propanoic,2-methyl-,ethyl ester and hexane,were the first three toppest content components.Compared with other species of Michelia,Dibutyl phthalate,cis-1-methoxy-1-butene and(z)-2-penten-1-ol acetate were first reported in Michelia skinneriana.VOCs released by insect-damaged Michelia skinneriana(13:00-15:00) contained 56 components,compared with healthy plants,2(Hexane and Heptadecane) were missing and 20 components were newly appeared.Of the 20 newly appeared components,5 kinds were hydrocarbons,of which the content of 1-hexene was relatively high.Besides,the contect of terpenoids was also high.All the above results showed that hydrocarbons,as well as terpenoids, took an important part in inducing Michelia skinneriana's chemical defense.The phenolics' content in healthy Michelia skinneriana's leaves was very low,at about 0.533 mg/g,whereas the content in near-contrastive and insect-damaged Michelia skinneriana plants were resperctively 1.033 mg/g and 1.133 mg/g.To some degree,the results showed that the phenolics were associated with Michelia skinneriana's induced chemical defense,and the near-contrastive plants apperceived a signal carring the information of the damage of Ceroplastes japonicus.The signal made the near-contrastive plants got ready for the insect damage in advance by increasing the phenolics's content.The plants were far from each other,the root-root contact could be excluded,so it's probably that VOCs took a part in the volatile signaling in plant-plant interactions.Of the 20 newly appeared components,ethylene,2-Propanol,2-methyl-,1-hexene which were small highly volatile compounds,diffused rapidly in air,so they couldn't be transported further, while MeSA,Limonene,Cedrene and(E)-α-bergamotene which had comparatively slower dispersal,were more likely to function as signal over longer distance.Limonene and 1-hexene were two newly appeared components in near-contrastive and insect-damaged Michelia skinneriana plants,their relative content had the same daily change current,that was rhythmicity.In a word, Michelia skinneriana enhenced its chemical defence mainly by means of two ways:one was increasing total mount of VOCs,the other was increasing the relative content of some special compounds.