Insecticidal activity ofLantana camaraextract oil on controlling maize grain weevils

Abstract

Postharvest losses are known to be one of the serious constraints upon food security among farmers poor resource in Africa. The use of botanical insecticide in pest management during storage against weevils is often encouraged because synthetic insecticides produce multiple side effects on human and environment. In this study, the insecticidal property of methanol, ethanol, and ethyl acetate extracts of Lantana camara leaf oil and powder for controlling maize weevils, Sitophilus zeamais, was studied. Gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy (FTIR) were used to identify the chemical composition and functional group of solvent extract, respectively. Adult weevil repellency and mortality were studied by the effect of oil concentration at 0% (w/w), 2% (w/w), 3% (w/w), 5% (w/w), 7% (w/w), and 10% (w/w). Repellency effect was also conducted at 6, 12, and 24 h. The number of weevil death increased significantly as exposed time was increased. The extracted oil by the three-solvent fraction had direct repellent and toxic effect to the weevil. From all treatment applied, extracted by methanol fraction had showed highest percentage mortality (74%). The lowest mortality rate was observed in ethyl acetate extract (26%) at 2% (w/w) concentration. The effect of leaf powder and extracted oil on repellency and mortality for insects was due to the presence of bioactive and phytochemical molecules such as Phytol, Pyrroline, Paromomycin, Pyrrolizin, and 1-Eicosano. It was concluded that both L. camara leaf powder and extract oil can be used for the protection of stored maize from infestation S. zeamais.

Potential insecticidal activity of four essential oils against the rice weevil, Sitophilus oryzae (L.) (Coleoptera: Curculionidae)

“…The powdered leaves of Spear grass (I. cylindrica) could serve as a safer alternative to synthetic insecticides for the maize weevil (S. zeamais) infestation in stored maize grains (Ehisianya et al 2019). Extracts from L. camara leaf were used for the stored maize protection against the infestation of S. zeamais (Ayalew 2020). Recently, Loko et al (Loko et al 2021) showed the good potential of C. citratus as both antifeedant and fumigant toxic agent against Dinoderus porcellus Lesne.…”

Composition, Seasonal Variation, and Biological Activities of Lantana camara Essential Oils from Côte d’Ivoire

“…Each essential oil and Talisma solution and the control were made in six replicates. After 24 hours, the number of dead weevils was counted and the weevil's mortality was calculated according to the following equation [81].…”

“…This test was used for each concentration, and the whole treatment was completed in triplicates. The repellent percentage (Pr) was calculated as follows [81].…”

Repellent and Toxic Effects of some Plant Extracts on Subterranean Termite Psammotermes hybostoma (Isoptera: Rhinotermitidae)

“…The toxic effect of L. camara was previously reported on tobacco caterpillar Spodoptera litura (Deshmukhe et al 2011), stored grain pests (Rajashekar et al 2014) cabbage white butterfly, Pieris brassicae (Sharma and Gupta 2009), and the rice moth, Corcyra cephalonica. Ayalew (2020) reported that stored maize could be protected from the infestation of S. zeamais by using extracts and oils of L. camara leaf and the author suggested that this repellent and mortality effect for insects could be because of the presence of bioactive compounds like 1-Eicosano, Paromomycin, Phytol, Pyrroline and Pyrrolizin. Alvi et al (2018) reported the toxic effect of R. stricta extract in controlling insect pests like Rhyzopertha dominica and Trogoderma granarium.…”