Fourth International Bemisia Workshop International Whitefly Genomics Workshop
Arthropod Predation on Bemisia tabaci on Cassava in Uganda: Preliminary Results from Molecular Gut Analysis
1 Insect Biocontrol Laboratory, USDA-Agricultural Research Service, Beltsville, MD, USA. Correspondence: greenstm@ba.ars.usda.gov
2 Eastern and Southern Africa Regional Center, International Institute of Tropical Agriculture, Kampala, Uganda
Cassava is second only to maize as a staple crop in Sub-Saharan Africa. Bemisia tabaci is the principle vector of African cassava mosaic disease (ACMD), which is responsible for greater reductions in cassava yield than any other pest in the region. As part of IPM research to reduce the incidence of ACMD, we are examining the potential of predators to suppress B. tabaci populations. Predators that we observed feeding on the whitefly include ants, coccinellid adults and larvae, Conwentzia larvae, and syrphid larvae. Using PCR primers designed to distinguish B. tabaci DNA from that of two abundant alternate prey, cassava green mite and cotton aphid, we screened a sample of all of these predators, and found positives only in syrphid larvae and larvae of an undescribed coccinellid of the genus Serangium. A larger sample disclosed no positives in Serangium adults (N=25), 8.3 % positives in Serangium larvae (N=24), and 92% positives in the syrphid larvae (N=24). Since the detectability interval for DNA can affect the interpretation of prey positives, we are performing B. tabaci half-life studies in these predators so that we can correctly weight these data and determine the relative importance of these two predators as natural enemies of B. tabaci.
|
PREVIOUS The Inside Story: Bacteriocyte-associated Endosymbionts of Whiteflies |
NEXT Monitoring of Imidacloprid Resistance in Biotype B of Bemisia tabaci in Florida |