Modeling Approach For Bemisia Tabaci Genn.ýþ þAnd Its ýParasitoids Eretmocerus Mundus Mercet And ýEncarsia Sp. In Jordan Valley.ý ýý ýý

Hazem Sharef Hasan ⁽¹⁾and Naim Sharaf ⁽²⁾ýý
⁽¹⁾Department of Agricultural sciences, Al-Shobak University Collage, Al-Balqa ýApplied University, Al Shobak, P.O. Box 5, Jordan, ýý
E-mail: Hazem@ju.edu.joý
⁽²⁾ Department of Horticulture and Plant Protection, Faculty of Agriculture, University ýof Jordan, Amman, Jordanýý
E-mail: Sharaf@ju.edu.joý

Abstract

A high parasitization rate was achieved when either E. mundus or ýýEncarsia sp. were released at the ratio of 2:1 (Adults Whitefly:Adult ýparasitoids). Parasitization ranged from 58.4-81.3% with a grand mean of 72.2% ýfor E. mundus, whereas it was between 38.1 and 81.5% for Encarsia sp. ýwith a grand mean of 75.8% for Encarsia sp. The net reproductive rate ýý(R₀) of whitefly females was drastically affected by the level of ýparasitoids released. At high release ratio of 2:1 as well as at an equal release ratio ýof 1:1, R₀ –values were very low as compared to the control. But at ýrelease ratios of 1:1.5 and 1:3, R₀ –values were relatively high ýexceeding sometimes R₀ ‘s of the control. The output of this study ýwas proposed in a model for biological control of B. tabaci based on adult ýcounts of whiteflies and on an inundative release of parasitoids, E. mundus ýor Encarsia sp. Whitefly parasitoids interaction in such a simple model ýrepresents parasitism rate close to those obtained in the field, since this model ýcoincides with 83% of the data (R²=0.83) in the case of E. ýmundus and 80% (R²=0.80) of the data in the case of ýEncasia sp. ý