Influence Of Humidity On The Development Of Athetis Lepigone And Preliminary Study On The Attractant Substance To Adult,Larvae Of A. Lepigone

Athetis lepigone (M schler)(Lepidoptera: Noctuidae) is a new insect pest insummer corn and causes serious damages to corn seedlings in China. The effect oftemperature and photoperiod on the development of A. lepigone have been studied.in ourlaboratory. In paper, influence of humidity on A. lepigone was conducted in order toprovide a theoretical basis for field predictions. It is very difficult to control this insectpest because it hide beneath the straw and bran of winter wheat after harvest bycombines. So it is important to study an attractant for larvae and sex pheromone of A.Lepigone. these results would provide foundation for controlling A. lepigone.The mainresults are as follows:1.Under laboratory conditions24℃,8humidity(25%,35%,45%,55%,65%,75%,85%,95%), the influence of humidity on the development of A. lepigone wereconducted.. The results showed that the developmental duration of A. lepigone shortedas humidity. raising..It was significant impact which humidity to survival for younglarvae and after3st instar,larvae has higher survival. The life expectancy of female,male increased as humidity raising. At85%RH, A. lepigone had the highest overallsurvival rate, the shortest generation duration (34.4d), the longest life expectancy,(female,15.2d;male16.6d.), the maximum number of eggs laid per female (409.2);thehighest population trend index(163.5) and rm(0.17). The results showed that the optimumhumidity for the development and fecundity of A. lepigone was85%RH.2. The taxis responses of larvae to straw, bran, wheat bran, fried wheat bran andcorn seedlings was tested by Y-tube olfactometer.The volatile components of fried wheatbran and wheat bran were analyzed by HS-SPME and GC-MS and six compounds, eightblends were selected to conduct the laboratory trapping.Results indicated that fried wheatbran were most attractive to larvae.2-heptanone(5μg/μL) showed the highest attractionto larvae (75.9%) in six compounds. Larvae of A. lepigone were strongly attracted to athree-component blend [2-heptanone＋benzaldehyde＋p-xylene](72.7%) in eight blends,but the attraction of three-component blend [2-heptanone＋benzaldehyde＋p-xylene]was lower than2-heptanone. The results showed that2-heptanone was the highestattractive to larvae of A. Lepigone.3. The sexual attraction of A. lepigone was studid., The results showed that malewere strongly attracted by female(75.35%), while male moth or female moth didn’thave attraction to the same sexual moth.This concluded sex pheromone of A. lepigone produced by female. The mating behavior of A. lepigone was studied.The resultsindicated mating activity began at1-2days of age, peak at3-4days of age.The matingbehavior occurred between21:00-2:00,reached peak at23:00.4. Sex pheromone of A. lepigone was abstracted with four solvents (n-hexane,n-pentane,petroleum ether, dichloromethane) and bioactivity was tested. Results showedthat the n-hexane extract of sex pheromone had the highest attraction(71.11%) to male.