Among tropical plant families, members of Annonaceae have great potential as a source of biopesticides. To develop an alternative tool for control of Helicoverpa armigera, efficacy of ethanolic extracts from seeds of five species belonging to the genus Annona (A. montana Macfad., A. mucosa Jacq., A. muricata L., A. reticulata L. and A. sylvatica A. St.-Hil.) and an acetogenin-based commercial bioinsecticide (Anosom Ò 1 EC, 10,000 ppm of annonin as the main active ingredient) were evaluated in a dietary exposure bioassays. In an initial screening, an ethanolic extract from A. mucosa seeds (LC 50 = 1479 ppm) and Anosom Ò 1 EC (LC 50 = 1151 ppm) were the most promising treatments. In addition to acute toxicity, pronounced inhibition of H. armigera larval growth was observed in both treatments. Using chromatographic techniques, bioguided fractionations were conducted and the acetogenin bis-tetrahydrofuran rolliniastatin-1 was isolated as the primary compound from the most active fractions of A. mucosa. At a concentration of 41.55 ppm, rolliniastatin-1 caused total mortality of H. armigera larvae after the fourth day of exposure. In greenhouse trials, extract of A. mucosa (as an emulsifiable concentrate formulation) and the botanical insecticide based on extract of Annona squamosa L. (Anosom Ò 1 EC), both at LC 90 values previously estimated, were compared with a diamide-based commercial insecticide (flubendiamide 480 SC) for mortality after 168 h of exposure to larvae on tomato plants; all treatments caused high larval mortality ([90%). Thus, the results of this study indicate that the derivatives of Annonaceae are a useful alternative for the integrated management of H. armigera. Keywords Annonaceae Á Acetogenin Á Botanical insecticides Á Old world bollworm Á Rolliniastatin-1 Á Chromatographic techniques Key message • Annonaceae species were screened to detect sources of insecticidal compounds. • An ethanolic extract from A. mucosa seeds caused strong mortality to Helicoverpa armigera. • The major compound present is the acetogenin bistetrahydrofuran rolliniastatin-1. • Ethanolic extract from A. mucosa seeds also caused high larval mortality in greenhouse trial. Communicated by M.B. Isman.

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-The objective of this work was to characterize the resistance of 50 cowpea (Vigna unguiculata) genotypes to Callosobruchus maculatus. A completely randomized design with five replicates per treatment (genotype) was used. No-choice tests were performed using the 50 cowpea genotypes to evaluate the preference for oviposition and the development of the weevil. The genotypes IT85 F-2687, MN05-841 B-49, MNC99-508-1, MNC99-510-8, TVu 1593, Canapuzinho-1-2, and Sanzi Sambili show non-preference-type resistance (oviposition and feeding). IT81 D-1045 Ereto and IT81 D-1045 Enramador exhibit antibiosis against C. maculatus and descend from resistant genitors, which grants them potential to be used in future crossings to obtain cowpea varieties with higher levels of resistance.

Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Middle East Asia Minor 1 is one of the most important pests of the common bean, due to its potential of causing direct and indirect damage. This study aimed to evaluate 78 bean genotypes to verify the occurrence of resistance of antixenosis type against B. tabaci. Initially, multiple-choice trials were performed to evaluate the oviposition preference and nymphs' establishment at 3 and 15 days after infestation. Subsequently, 21 bean genotypes were selected, and a no-choice test was conducted. Colorimetric analyses were performed to establish correlations between leaf color and insect establishment. In multiple-choice trial, the genotypes BRS

The silverleaf whitefly Bemisia tabaci biotype B is one of the most important sucking pests of common bean, which causes severe damages and requires frequently synthetic insecticides spraying to protect crop productivity. The use of common bean cultivars resistant to whitefly attack is an important strategy within an integrated pest management (IPM) program. The biological development of B. tabaci confined to 17 bean genotypes was evaluated in greenhouse trials to verify the occurrence of antibiosis. Whitefly adults were released on plants of these genotypes to oviposit, afterward the incubation period of eggs, nymphal period, complete development period (egg-adult), and viability of the silverleaf whitefly nymphs were recorded. As main results, genotype CHIP 300 prolonged the developmental period from egg to adult (~10 days) and BRS Estilo, Arcelina 4, IPR Garça, Tybatã, CHIP 300, IPR Eldorado, H96A102-1-1-1-52, SCS-202-Guará and CHIB 06 caused nymphal mortality, suggesting high levels of antibiosis and/or antixenosis. These genotypes may be helpful in common bean breeding programs aimed at developing commercial cultivars resistant to B. tabaci biotype B.