Studied On The Controlling Effect Of Neoseiulus Sp. To Panonychus Ctri Aagregor And Setted Up Its Experimental Population Life Tables

Neoseiulus sp.is a species of predatory mites. It prey on pests of Panonychus ctri AaGregor. Tetranychus cinnabarinus (Boisduval), Eotetranychus kankitus (Ehara)and so on. It was identified as a new record species in China by the researcher of Xu Xuenong in Plant Protection Institute of Chinese Academy of Agricultural Sciences. The research object of this paper was Neoseiulus sp. Studied on the controlling effect of Neoseiulus sp. against P.ctri AaGregor and setting up its experimental population life tables. The main results are the following:1. Functional responses of Neoseiulus sp.and other predatory mites to P.ctri AaGregor Studied the functional responses of the adult of Neoseiulus sp., A.fallacies (Garman), Euseius nicholsi and A. pseudolongispinosus towards P.ctri AaGregor at different stages. It was found that the functional responses of the4species of predatory mites were all belonged to Holling Ⅱ types. The result showed that the controlling effect of Neoseiulus sp. to P.ctri AaGregor was weaker than A.fallacies (Garman), stronger than A.pseudolongispinosus, and equivalent to E.nicholsi from compared the functional response parameter a, Th.,Namax and alTh, of the4species of predatory mites. The Neoseiulus sp. has strong controlling effect to P.ctri AaGregor egg, the predation number of A.fallacies (Garman) to P.ctri AaGregor egg was little and E. nicholsi hardly feeding P.ctri AaGregor egg, So the value of using Neoseiulus sp. to control P.ctri AaGregor was greater than A.fallacies (Garman) and E.nicholsi.2. Effected of temperature on functional response of Neoseiulus sp. studied the predation functional response of the adult Neoseiulus sp. to P.ctri AaGregor at different stages in the experimental temperature range of20to34℃. The results showed that the functional response of Neoseiulus sp. to P.ctri AaGregor at different stages was belonged to Holling Ⅱ types in different temperatures. The controlling effect of Neoseiulus sp. to P.ctri AaGregor was increased in the experimental temperature range of20to30℃, the controlling effect is strongest at30℃, but when the temperatures beyong34℃, the controlling effect decreased.3. The starvation tolerance in high temperature of Neoseiulus sp. Compared the starvation tolerance of Neoseiulus sp., A.pseudolongispinosus, A.makuwa Ehara, A.fallacies (Garman) and E.nicholsi, In high temperature conditions of34℃. The results showed that, the starvation tolerance in high-temperature of Neoseiulus sp. is higher than A.fallacies (Garman) and E.nicholsi.and close to the A. pseudolongispinosus and A. makuwa Ehara.4. The controlling effect of Neoseiulus sp. to P.ctri AaGregor on plane Studied the controlling effect of Neoseiulus sp. to P.ctri AaGregor in different proportion of benefits and harm. The results showed that,when the proportion of benefits and harm is3:30. the number of Panonychus ctri AaGregor started reducing from the3rd day, and was controled after the7th day.5. The diffusibility and controlling effect of Neoseiulus sp. to P.ctri AaGregor on the citrus. Neoseiulus sp. can actively migrate and diffuse,and normally reproduce on citrus, it have fine features of the natural enemies. After released the predatory mite15days. The decresae rate of P.ctri AaGregor is93.15%, and control effects reached98.58%in release group. Neoseiulus sp. can well control P.ctri AaGregor in space.6. The impact of temperature on growth and development of Neoseiulus sp. The developmental duration of Neoseiulus sp. was shortened with temperature increasing in16,19,22,25,28and31℃, but the developmental duration prolonged at34℃. The developmental duration of the generation of the mite are respectively21.91,14.53.9.67.7.57,6.34.5.75and6.45d under different temperature conditions. The developmental threshold temperature and effective accumulated temperature of the whole generation of Neoseiulus sp. was respectively11.09℃and109.14day-degrees. Fitted the relationship between developmental rate and temperature of Neoseiulus sp. by the linear model logistic model and the model by Wang Rusong et al., the results shows that, Wang Rusong model can well describe the phenomenon of developmental rate of Neoseiulus sp. reduced at higher temperatures. The range of the fittest temperature for Neoseiulus sp.at diffenent stages to develop was24.13～27.95℃,and the fittest temperature for Neoseiulus sp. at whole stage was26.61℃by Evaluation of parameters of the Wang Rusong model model.7. Experimental population life table of Neoseiulus sp. Setted the experimental population life table of Neoseiulus sp. at7constant temperature(16,19,22,25,28,31and34℃). The results shows that, Neoseiulus sp. can complete its life history in experimental set temperature conditions. Compared the life table parameters of experimental population for Neoseiulus sp.,the results shows that,the range of the fittest temperature for Neoseiulus sp. to Propagate was25～31℃,and the fittest temperature for Neoseiulus sp. to Propagate was28℃.