Repellence and deterrence on oviposition of Bemisia tabaci biotype B by the use of vegetal extracts in Cucurbita pepo L

J.P.G.F. Silva R.R.C. Zaché E.L.L. Baldin F.B. Oliveira E.R Valtapeli About the authors

Bemisia tabaci biotype B is one of the main pests in squash (Cucurbita pepo L.). The management of this whitefly has become a major challenge to growers, since they have the ability to quickly develop resistance to different classes of insecticides. Alternatively, the use of plant extracts with insecticide and/or insectistatic activities has been investigated, showing promising results for the whitefly control. The present study evaluated the possible effects of seven extracts from five plant species, Ruta graveolens L. (leaves), Azadirachta indica A. Juss. (leaves + branches), Trichilia pallida Swartz (branches), T. pallida (leaves), A. indica (almonds), Chenopodium ambrosioides L. (inflorescence + leaves + branches) and Mentha pulegium L. (leaves) on Bemisia tabaci biotype B in squash, by assays of repellence and oviposition deterrence. In free choice tests, the attractiveness and determination of the rate of repellence (with 6, 24 and 48 hours after application of the extracts) were evaluated. The oviposition was observed after the third counting of the number of adults. The extract of leaves of M. pulegium showed repellence and oviposition deterrence to B. tabaci biotype B and may be recommended as an alternative in the insect management.

Curcubitaceae; whitefly; plant extracts; alternative management

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