Host Treatment Strategies Of Two Parasitoids Of Bemisia Tabaci (Gennadius) B-biotype

Bemisia tabaci (Gennadius) B-biotype is one of the most important pest insects of vegetables, broadleaf field crops, and ornamentals in the tropics and subtropics of the world and under protected environments in other areas. Damage is caused not only by direct feeding, but also through transmission of viral diseases. B. tabaci B-biotype also damage plants by inducing physiological disorders such as irregular ripening in tomato. Biological control could be an attractive management alternative for those whiteflies. Nearly a century, the history of pest control around the world amply demonstrated, the introduction of natural enemies is one of the best strategy for invasive pests,which can be abundant local natural enemies to improve the local insect community structure, and thus economic, security and sustained effective control invasive pests, parasitic wasps ecological agriculture and forestry Important pest biocontrol system substrate, therefore, this paper use Eretmocerus hayati andEncarsia sophia which are two obligate and dominant parasitic wasp of whitefly advantage as the research object, from the following three aspects studied these two parasitic wasp:1. Er.hayati and En.sophia structural anatomy of the female reproductive system.2 .The host adaptation of Er.hayati on different ages of nymphs to B.tabaci.3 .The effect of host density on the parasitism and Feeding Strategies of Er. hayati and En.sophia.The following results:1. Both parasitoid females had two ovaries and each had three ovarioles. The numbers of mature ova in 6 or 24 h-old Er. hayati female were higher than that in En. sophia, respectively, which was coincident with the results of oviposition experiment indicating that the number of host parasitized by 24 h-old Er. hayati female was higher than that by 24 h-old En. sophia female, and the number of host fed was lower than that of En. sophia.2. Fecundity increase with host age and a significant reduction in the B. tabaci B-biotype one instar nymphs of eggs on the highest single-day female fecundity is 10.2; with host age and the increase in parasitic wasps Shorten development time, in the early fourth instar whitefly nymphs on the shortest development time, the immature development time was 13.5 days; female and male sea wasp's propeller angle of aphids in instar whitefly nymphs 1 to 4 on the whole child Development time period there was no significant difference in the survival rate of 75.2%immature, male and female sex ratio of 0.92~1.43.3. At a single host age, different trade-off parasitic wasps different emphasis: when the host density is lower, Er. hayati tends to meet the reproduction needs firstly.; En. sophia tends to first meet the nutritional needs. Under the different host age, when the host density is lower, Er. hayati will priority find the optimal hosts to spawn,and feed the Alternative age hosts. when the host density is higher,the spawning and feeding of Parasitoid all tend to select the the optimal age hosts; En. sophia will feed optimal hosts after meeting their basic breeding.