Host instar suitability of Bemisia tabaci (Genn.) (Hom.: Aleyrodidae) for the parasitoid Eretmocerus mundus (Hym.: Aphelinidae)

Efficient use of parasitoids in pest control depend on the knowledge of the biological relationships between host and parasitoid. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) is one the most important natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) that is found in fields and greenhouses in Adana, Turkey. Although more studies have been done to determine the relationships between E. mundus and B. tabaci, the differences among strains of E. mundus could have important biological concequences. In this study, biological characteristics of native population of E. mundus parasitization of B. tabaci (Q biotype) were determined using bean plants Phaseolus vulgaris (L.) at a constant temperature of 25 ± 1°C, relative humidity 70 ± 10% and 16:8 (L:D) photoperiod regimen. All B. tabaci nymphal instars were parasitized by E. mundus, but the mean number of daily-parasitized nymphs was highest in the second instars (15.3). In addition, second instar females had the shortest mean development time (15.2 days). Mean development times of parasitoids obtained from first, second, third and fourth B. tabaci instars varied from 15.2 to 16.2 days and 15.2 to 15.9 days for female and male, respectively. Proportion of female (+/male;++) varied from first (0.53) to second (0.34) host instars. Impact of results on potential biological control of B. tabaci was discussed through conservation native natural enemies. © Springer-Verlag 2006.TUBÃTAK-TOGTAG-3037Acknowledgments I would like to acknowledge Prof. G. Viggi-ani (CNR, Ist Protez Piante, Sez Portici, Portici, I-80055 Italy) and Dr. J. L. Cenis (CIDA La Alberca, Murcia, Spain) for the parasitoid and whiteXy identiWcation. I appreciate the comments and review of the manuscript by Dr. Steve J. Castle and Dr. C. C. Chu (Western Cotton Research Laboratory, Phoenix, AZ). I also would like to thank Dr. Cengiz Kazak and Dr. M. Rifat Ulusoy (Çukurova University, Adana, Turkey) for their valuable suggestions on early version of the manuscript. This work was supported by the ScientiWc and Technical Research Council of Turkey (TUBÃTAK-TOGTAG-3037)