title: Rational Practices to Manage Boll Weevils Colonization and Population Growth on Family Farms in the Semiárido Region of Brazil.
abstract: Because boll weevil, Anthonomus grandis Boh. develops partially protected inside cotton fruiting structures, once they become established in a field, they are difficult to control, even with nearly continuous insecticide spray. During two cotton-growing seasons in the Semiárido region of Pernambuco State, Brazil, we tested the use of kaolin sprays to disrupt plant colonization through visual cue interference, combined with removal of fallen fruiting bodies to restrain boll weevil population growth after colonization. Kaolin spray under non-choice trials resulted in 2.2×, 4.4×, and 8.6× fewer weevils, oviposition and feeding punctures on kaolin-treated plants, respectively, despite demonstrating no statistical differences for colonization and population growth. Early season sprays in 2010 occurred during a period of rainfall, and hence, under our fixed spraying schedule no significant differences in boll weevil colonization were detected. In 2011, when kaolin sprays were not washed out by rain, delayed boll weevil colonization and reduction on attacked fruiting bodies were observed in eight out of 12 evaluations, and kaolin-treated plots had 2.7× fewer damaged fruiting bodies compared to untreated plots. Adoption of simple measures such as removal of fallen fruiting bodies and prompt reapplication of kaolin sprays after rainfall show promise in reducing boll weevil infestation.
authors.affiliation: Departamento de Agronomia-Entomologia, Universidade Federal Rural de Pernambuco. Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, 52171-900, Brazil. roberiocneves@yahoo.com.br.
authors.forename: Robério C S
authors.initials: RC
authors.lastname: Neves
authors.affiliation: Departamento de Agronomia-Entomologia, Universidade Federal Rural de Pernambuco. Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, 52171-900, Brazil. fcolaresbatista@yahoo.com.br.
authors.forename: Felipe
authors.initials: F
authors.lastname: Colares
authors.affiliation: Departamento de Agronomia-Entomologia, Universidade Federal Rural de Pernambuco. Rua Dom Manoel de Medeiros, s/n, Dois Irmãos, Recife, 52171-900, Brazil. jtorres@depa.ufrpe.br.
authors.forename: Jorge B
authors.initials: JB
authors.lastname: Torres
authors.affiliation: Departamento de Fitotecnia, Universidade Federal de Viçosa. Av. Peter Henry Rolfs, s/n, Campus Universitário, Viçosa, 36570-000, Brazil. roberta.leme@ufv.br.
authors.forename: Roberta L
authors.initials: RL
authors.lastname: Santos
authors.affiliation: Instituto Central de Ciências Ala Sul (ICC-Sul), Faculdade de Agronomia e Medicina Veterinária (FAV), Universidade de Brasília (UnB), Brasília, 70910-900, Brazil. cschetino@unb.br.
authors.forename: Cristina S
authors.initials: CS
authors.lastname: Bastos
keywords: cultural control; integrated pest management; kaolin; physical control