Avalia??o de extratos vegetais no controle de mosca-branca, Bemisia tabaci biótipo B em abóbora

摘要

The squash (Cucurbita moschata Duch.) is an important crop for family farmers in the northeast of Brazil. However, the occurrence of leaf silvering caused by the whitefly, Bemisia tabaci biotype B, limits production, causing losses to farmers. The aim of this study was to evaluate the efficiency of plant extracts on the population levels of whitefly nymphs on the squash cv. Jacarezinho. The experiment was conducted at an experimental field, in a randomized block design consisting of six treatments and three replications. Applications of plant extracts were made at an interval of seven days, making use of substances extracted from the following plants: Ipomoea carnea subsp. Fistulosa, castor bean (Ricinus communis L.), Tingui (Mascagnia rigida Griseb), cardo-santo (Argemone mexicana L.), and the commercial oil product Natuneem ?. All of the plant extracts were efficient in the control of the B. Tabaci nymphs, with R. communis (75.49%), M. rigida (73.99%), I. carnea (72.24%), neem oil (70.4%) and A. mexicana (69.16%).