The Effect Of Monoterpene Volatiles And Jasmonates From Slow-release Treatments On Dendrolimus Superans Behavioral Interference

Larix gmelinii terpene volatiles of influence Dendrolimus superans insect behaviors with many monoterpenes being highly volatile.In order to control release of such active volatile compounds and to maintain a certain active duration,three major Larix gmelinii needle related volatiles a-pinene?myrcene and camphene were chosen for experiment:(1)respectively formulated into chitosan-based slow-release microcapsules via monophasic coagulation;(2)poured into the slow-release bottles.Each slow-release treatment of volatile compound was spayed onto 2-year old L.gmelinii seedlings in comparison with those spayed with the corresponding solutions made straight from the volatile compounds,and measured the activities of several major defense protein in larch needles.Simultaneously,choosing exogenous methyl jasmonate signal substances and jasmone poured into the slow-release bottles,spayed onto 2-year-old larch trees,and measured the activities of several major defense protein in larch needles,to maintain a certain active duration of induced resistance of larch.The main results are as follows:1.Preparation of terpenes volatiles slow-release microcapsules and microcapsules suspensionsMyrcene,a-pinene,camphene were respectively formulated into chitosan-based slow-release microcapsules via monophasic coagulation.Myrcene,?-pinene microcapsules core-wall ratio were 3:1;camphene core-wall ratio was 4:1,significantly influence Dendrolimus superans insect behaviors.Microcapsule suspension formula:disperser was 0.1%tween20 with 0.3%calcium chloride;anti-settling agent was 0.1%sodium carboxymethyl cellulose.The susupensibility of volatiles microcapsule suspensions was more than 90%,which is in the line with the requiements of the experiment.2.The slow-release effect determination of volatiles microcapsule suspensions(1)Our results from lab Y-tube bioassay showed that a-pinene and myrcene from the solutions were significantly attractive to D.superans female adults(P<0.01)at day one.Seedlings sprayed with the slow-release microcapsule suspensions of a-pinene and myrcene also showed significant attraction to D.superans female adults for four days.Camphene from the synthetic solution showed significant repellency(P<0.01)at day one,and seedlings sprayed with the slow-release microcapsule suspension also showed significant repellency effect for four days.(2)The outdoor caging bioassays showed that microcapsule suspensions of ?-pinene and myrcene significantly increased female oviposition(number of eggs),whilst the microcapsule suspension of camphene significantly reduced the number of eggs laid on treated seedlings.These effects from these slow-release microcapsule suspensions lasted for three days.Our data suggest that microcapsule of these highly volatile compounds such as monoterpenes with chitosan may provide a feasible control release formulation to extend their effective life-span(duration).3.The slow-release effect determination of volatiles release bottles(1)Seedlings suspended with the slow-release bottles of a-pinene and myrcene showed significant attraction to D.superans female adults for five days.Seedlings suspended with the slow-release bottles of camphene also showed significant repellency effect for four days.(2)The outdoor caging bioassays showed that slow-release bottles of a-pinene and myrcene significantly increased female oviposition(number of eggs)whilst the slow-release bottles of camphene significantly reduced the number of eggs laid on treated seedlings.These effects from these slow-release bottles lasted for three days.Our data suggest that slow-release bottles with these highly volatile compounds may provide a feasible control release formulation to extend their effective life-span(duration).4.Effect of L.gmelinii needle related volatiles on activities of defense proteins and secondaty metabolites in the needles of L.gmeliniiL.gmelinii seedlings in with spayed with the corresponding solutions made straight from the volatile compounds and slow-release treatment,the change of activities of several major defense protein in larch needles were not signigicant.This shows that a single a-pinene,myrcene or limonene does not make activities of several major defense protein in larch needle change,and does not enhance induced resistance of larch.5.Effect of slow-release treatments of exogenous jasmonates on activities of defense proteins in the needles of L.gmeliniiThe activities of defense proteins increased signigicantly in the needles of L.gmelinii induced by exogenous jasmonates and slow-release treatments.The variation of their activity was waved in the period of the experimentation.Our data suggest that slow-release bottles with these jasmonates may provide a feasible control release formulation to extend their effective life-span(duration)of enhancing induced resistance of larch at least for five days.