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

Abstract

SummaryThe 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.

Synergetic effects of two botanical entomocides as pest-protectants in maize grains

“…Javid and Poswal 49 reported that admixing 2% (w/w) powdered flower buds of Syzigium aromaticum with cowpeas prevented oviposition and emergence of Callosobruchus maculatus. This is also in agreement with the findings of Adedire and Akinneye, 50 and Adesina et al 23 who found E. aromatica and A. melegueta significantly reduce or prevent the oviposition and adult emergence of C. maculatus on cowpea. The ability of the evaluated plants to significantly (P<0.05) suppress adult emergence suggested that the plants might possess ovicidal and larvicidal properties.…”

Essential oil extract from <i>Moringa oleifera</i> roots as cowpea seed protectant against cowpea beetle

“…The current result agrees with previous researchers (Adedire and Akinneye, 2004;Mbailo et al, 2006), who showed that powder and ethanolic extracts of tree marigold, Tithonia diversifolia, seed oils from Azadiracta indica, Ricinus communis, Thevetia nerifolia, Balanites eagyptiaca, Moringa oleifera and Khaya senegalensis protected the stored cowpea seeds against Callosobruchus maculatus infestation.…”

Effect of weed extracts against pulse beetle, Callosobruchus chinensis L. (Coleoptera: Bruchidae) of mung bean

“…The ingredients of these weeds may have the ability to inject into the body of the beetles and dysfunction their nutritional balance, thus caused mortality. Adedire and Akinneye (2004) reported the mortality effect of Tithonia diversifolia flower extracts on C. maculatus. Botanical insecticides offer broad spectrum toxic substances that interrupt insect's normal physiology and behavior, and influence on their feeding, mating, oviposition and mortality (Fouad et al, 2014).…”