Biological activity of tree marigold, Tithonia diversifolia, on cowpea seed bruchid, Callosobruchus maculatus (Coleoptera: Bruchidae)

• Published in: Annals of applied biology Vol. 144; no. 2; pp. 185 - 189
• Main Authors: Adedire, C.O, Akinneye, J.O
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.2004; Blackwell
• Subjects: application rate; Biological and medical sciences; biological control; botanical insecticides; Bruchidae; Callosobruchus maculatus; cowpeas; eclosion; Fundamental and applied biological sciences. Psychology; insect control; insect pests; insecticidal properties; leaf extract; leaf powder; leaves; mortality; oviposition; plant extracts; powders; seeds; storage insects; Tithonia diversifolia; Vigna unguiculata; Nigeria; Plant production; leaf extract; Tithonia diversifolia; Coleoptera; Insecta; Mortality; Biology; Extract; Plant leaf; oviposition; Callosobruchus maculatus; Powder; leaf powder; Arthropoda; Egg laying; Bruchidae; Invertebrata; Applied research
• ISSN: 0003-4746; 1744-7348
• DOI: 10.1111/j.1744-7348.2004.tb00332.x

Summary The powder and ethanol extract of Tithonia diversifolia leaves were tested for their efficacy at five different concentrations (0.0%, 0.5%, 1.0%, 1.5% and 2.0%) on bruchid mortality, oviposition and adult emergence of cowpea seed beetle Callosobruchus maculatus at ambient tropical storage conditions of temperature and relative humidity. Results showed that the leaf extract had a higher bioactivity on oviposition, adult emergence and mortality of C. maculatus. The mean number of eggs laid on seeds treated with extract was reduced from 20.7 in the solvent‐treated to 4.7 at 2%Tithonia extract concentration while adult emergence reduced from a mean of 92.2 in the solvent‐treated seeds to 72.2 at 2.0% extract treatment. Mortality was 100% at higher concentrations of 3%, 4% and 5% within 24 h of extract application but at lower concentrations mortality was 73.3% and 93.3% at 1% and 2%, respectively after 24 h. Fourty‐eight hours after application, 100% mortality of adult C. maculatus was obtained at all concentrations. The mean number of eggs laid was reduced from 41.3 in the untreated to 17.3 at 2.0% powder concentration while adult emergence dropped from 98.5% in the control to 74.2% at the highest powder concentration. The powder was effective at higher concentrations and longer exposure time. At 3%, 4% and 5%, 63–75% mortalities occurred within 24 h of application while at 48 h, mortality was 76–98% at 3–5% powder application rates. The results of this study revealed T. diversifolia as a potential candidate for bioinsecticide preparations because of antiovipositional, ovicidal and knockdown properties of its products, which have some volatile components.