The Effects Of Volatile Semiochemicals On Trichogramma Ostriniae (Hymenoptera: Trichogrmmatidae) Behavioral Mediation And Parasitism Potential In Artificial Host Eggs

Volatile semiochemicals is not only the key of relationship between plant, herbivore and its natural enemy but also the foundation for the theory and practice of IPM. It was reported that the effect of hexane extracts of Asian corn borer (ACB), Ostrinia furnacalis (Guenée ) female moth scale, egg masses and accessory glands of their different physiological stages on host selection behavior of Trichogramma ostriniae and host marking pheromones and experiences on oviposition behavior of its.It was also reported that volatiles semiochemicals affects parasitism potential in artificial host eggs and the main components were analized by GC-MS. At last, we researched on Trichogramma ostriniae reared in artificial host eggs and a new way that reproduces two and many kinds of Trichogramma in one artificial host eggs.1.The effect of volatile infochemicals on host selection behavior of Trichogramma ostriniaeThe effect of hexane extracts of Asian corn borer (ACB), Ostrinia furnacalis (Guenée ) female moth scale, egg masses and accessory glands of their different physiological stages on host selection behavior of Trichogramma ostriniae were measured by using a Y-tube olfactometer in the laboratory. The results indicated that the hexane extracts of ACB scale at the concentrations 0.5 mg/mL and 1 mg/mL exhibited significant attraction for T. ostriniae. The hexane extracts of ACB egg masses at the concentrations 5 egg masses/mL and 10 egg masses/mL clearly stimulated intensive search behavior by T. ostriniae females; the hexane extract of ACB egg masses at the concentration 40 egg masses/mL, however, had extremely significant repellent action to T. ostriniae females. The hexane extract of female accessory glands of mated-females before their first oviposition and at the earlier stage after oviposition stimulated intensive search behavior by T. ostriniae females; the hexane extract of female accessory glands of virgin females and the older stage after oviposition, however, did not elicit the parasitoid's reaction. The hexane extracts of female accessory glands and egg masses elicited stronger reaction by the parasitoid, but without significant difference between both obviously.2. Volatile infochemicals of ACB are analized by GC-MSHexane extracts of Asian corn borer (ACB), Ostrinia furnacalis (Guenée ) female moth scale, egg masses and accessory glands of their different physiological stages that were analized by GC-MS.It had been demonstrated that the main components were Hexadecanoic acid, Octadecanoic acid and its alkene, ester derivatives. The proportion of chemicals of Heneicosane,Doca- -sane,Tetracosane and Tricosane and so on are also not too fewer. It is obviously difference that the main compenents , the allocated proportion and comparative content of Hexane extracts of between Asian corn borer (ACB), Ostrinia furnacalis (Guenée ) female moth scale and other extracts.It is no obviously difference that the main components beween the others but the allocated proportion and the comparative content are. The hexane extracts of female moth scale,female accessory glands and egg masses elicited reaction contact with the main compenents , the allocated proportion and comparative content of its.3. Effects of Host marking pheromones and experiences on oviposition behavior of Trichogramma ostriniaeIt was reported that host marking pheromones (HMP)and experiences affect oviposition behavior in Trichogramma ostriniae.The results indicated that the oviposition process includes the stages of Antennal drumming, Drilling, Oviposition, Dring out and Winding up and so on; female wasps deposit HMPs on the chorion of host eggs with her ovipositor near the end of egg-laying process. Na?ve females do not posses the ability for recognizing the marking pheromones and have to obtain the ability though the learning process, in which the wasp inserts her ovipositor into a host egg to determine whether the egg has been parasitized followed by antennal drumming on the exterior . Once the learning process is completed, the female wasp will be able to discriminate between parasitized and unparasitized hosts and reject a parasitized egg by simply drumming on the exterior of the egg. Learning plays an important role in reducing initial rejection time when an unsuitable host is encountered. Female wasps of T. ostriniae can quickly learn to associate the presence of a HMP on host egg chrion with the internal status of the egg. The results of this study has enriched the ecology theory and provided the scientific basis for the better application of T. ostriniae in biological control.4.Effect of the host and Volatile infochemicals of ACB on rearing Trichogramma ostriniae by artificial host eggsArtificial diet for rearing Trichogramma ostriniae , plays an important role in biological control . We research on artificial host eggs for rearing the wasp by two methods , one is refinement of larvae and pupae of Asia corn borer (ACB) Ostrinia furnacalis Guenée based artificial diet for rearing the wasp, the other is artificial host eggs treated by attractant agents for rearing the wasp. The results indicates that The diet was based on different proportions of component of larvae and pupae used as a substitute for Tussah Antheraea pernyi pupae, was found to markedly improve the parasitic rate of the wasp, but not to producing larva to papu transition and pupa to adult transition, the larvae were drowned by unnecessary diet because of nutrition redundancy ; artificial host eggs treated by hexane extracts of Asian corn borer Ostrinia furnacalis Guenée female moth scale and egg masses showed that the parameters that evaluate successful rate of Trichogramma were significantly improved, the wasp developments and transition from pupa to adult were completed but successful rate of its is comparatively lower. In the all,the key point of the work for rearing Trichogramma by artificial host eggs is to resolve the problem that excessive nutrition of artificial diets.5. A new method that Trichogramma reared is devised by us, named"jiao xiang"A new method devised that reproduce two and more kinds of Trichogramma in one AHE by altering certain conditions of reproduction of it.The experiment is a attempt for Trichogramma ostriniae reared in AHE by altering time when Trichogramma ostriniae and Trichdgramma dendrolimi introduced. The results indicated when Trichdgramma dendrolimi introduced after Trichogramma ostriniae entered in AHEs for about 12 h is better to the development of Trichogramma ostriniae,the other times are not. The experiment prove the new method is feasible,but it is superficial.