Semiochemical modulation of host preference of Callosobruchus maculatus on legume seeds. (July 2015)

• Record Type: Journal Article
• Authors: Ajayi, Olufunmilayo E.; Balusu, Rahmmohan; Morawo, Tolulope O.; Zebelo, Simon; Fadamiro, Henry
• Is Part Of: Journal of stored products research. Volume 63(2015)
• Page Start: 31
• Page End: 37
• Publication Date: 2015-07
• Subjects: Semiochemicals -- Cowpea -- Callosobruchus maculatus -- VOCs -- GC-EAD -- GC–MS; Food -- Storage -- Periodicals; Farm produce -- Storage -- Diseases and injuries -- Periodicals; Entomology -- Periodicals; Food Contamination -- Periodicals; Food Preservation -- Periodicals; Insect Control -- Periodicals; Aliments -- Entreposage -- Périodiques; Produits agricoles -- Entreposage -- Maladies et dommages -- Périodiques; Electronic journals; 631.568
• DOI: 10.1016/j.jspr.2015.05.003
• Languages: English
• ISSNs: 0022-474X

Abstract

Abstract: Host preference of Callosobruchus maculatus (F.) on seeds of three legume cultivars, Ife-brown and black-eyed cowpeas [ Vigna unguiculata L. (Walp)], and soybean ( Glycine max L.), was investigated. Mated female C. maculatus showed high (90–95%) attraction to the three legume cultivars in Y-tube bioassays. However, the weevils discriminated among the cultivars in four-choice tests and showed greater attraction to Ife-brown cowpea (50%) than to soybean (30%) and black-eyed cowpea (15%). Coupled gas chromatography-electroantennography (GC-EAD) and GC–MS analyses of the headspace volatile organic compounds (VOCs) emitted by the legume seeds identified 2-ethyl hexanol as the principal EAD active component. Emission of 2-ethyl hexanol was two-fold greater in Ife-brown cowpea (∼0.54 μg g −1 seeds) compared with black-eyed cowpea (∼0.23 μg g −1 seeds) and soybean (∼0.21 μg g −1 seeds). Synthetic 2-ethyl hexanol attracted 68% of female C. maculatus at 0.01 μg dose in Y-tube bioassays. These results demonstrated that host preference in C. maculatus is odor-mediated, and identified 2-ethyl hexanol as a potential attractant for C. maculatus . Graphical abstract: Highlights: We studied response of Callosobruchus maculatus to odors of three legume seeds. GC-EAD and GC-MS revealed 2-ethylhexanol as the bioactive component. Pure 2-ethylhexanol attracted the weevils at 0.01 µg dose. Host preference in C. maculatus is odor-mediated. 2-ethyl hexanol is a potential attractant for C. maculatus .