Natural Enemies of the Bandedwing Whitefly 1 in Louisiana 2

Abstract

Species of the genera Eretmocerus and Encarsia (Order: Hymenoptera, Family: Eulophidae) are parasites of the bandedwing whitefly, Trialeurodes abutilonea (Haldeman) in Louisiana cotton and soybean agroecosystems. In the order of their prevalence, they are: Eretmocerus haldemani Howard, Encarsia species (undescribed), Encarsia quaintancei Howard, and Encarsia pergandiella Howard. E. haldemani is the predominant species both in cotton fields and in other host crop fields within cotton producing areas, accounting for ca. 70% of all parasites. Pupal parasitism was lower in cotton than other crop fields. Insect predators of the whitefly in Louisiana are as follows: Coleomegilla maculatalengi Timberlake, Coccinella novemnotata Herbst, Hippodamia convergens Guerin-Menaville, Olla abdominalis (Say), Delphastis pusillus LeConte; Geocoris punctipes (Say), Orius insidiosus (Say); species of Chrysopidae and Hemerobiidae; and Nabis species. Mixtures of broad spectrum insecticides such as methyl parathion, toxaphene and DDT used in cotton fields for the control of boll weevil and Heliothis species were extremely harmful to both parasites and predators of T. abutilonea .