The Phytochemical Composition of Melia volkensii and Its Potential for Insect Pest Management

Abstract

Due to potential health and environmental risks of synthetic pesticides, coupled with their non-selectivity and pest resistance, there has been increasing demand for safer and biodegradable alternatives for insect pest management. Botanical pesticides have emerged as a promising alternative due to their non-persistence, high selectivity, and low mammalian toxicity. Six Meliaceae plant species, Azadirachta indica, Azadirachta excelsa, Azadirachta siamens, Melia azedarach, Melia toosendan, and Melia volkensii, have been subject to botanical pesticide evaluation. This review focuses on Melia volkensii, which has not been intensively studied. M. volkensii, a dryland tree species native to East Africa, has shown activity towards a broad range of insect orders, including dipterans, lepidopterans and coleopterans. Its extracts have been reported to have growth inhibiting and antifeedant properties against Schistocerca gregaria, Trichoplusia ni, Pseudaletia unipuncta, Epilachna varivestis, Nezara viridula, several Spodoptera species and other insect pests. Mortality in mosquitoes has also been reported. Several limonoids with a wide range of biological activities have been isolated from the plant, including volkensin, salannin, toosendanin, trichilin-class limonoids, volkendousin, kulactone among others. This paper presents a concise review of published information on the phytochemical composition and potential of M. volkensii for application in insect pest management.

Evaluation of ten botanical insecticides against the sweet potato Weevil, Cylas formicarius (Fabricius, 1798) (Coleoptera: Brentidae)

“…Moreover, it has been shown that pyrethrin has no significant negative impact on non-target organisms (Papanikolaou et al, 2018). Toosendanin had no repellence activity, but strong antifeedant activity with an anti-feeding rate of 97.87% at a concentration of 2 g•L -1 (Jaoko et al, 2020) and moderate toxicity (with an adjusted mortality rate of 56.67% after 72 h of treatment at a concentration of 2 g•L -1 ) (Ma et al, 2013). The preliminary experiment also identified its high fumigation activity (the mortality rate of 0.1 g of raw insecticide was 92.0% after 24 h of treatment, unpublished data).…”

“…Their active ingredients are the secondary metabolites produced by the plant secondary metabolic pathway. These can effectively control a wide range of insect pests, including Spodoptera littoralis (Brem et al, 2002), Xanthogaleruca luteola, Ostrinia nubilalis (Jaoko et al, 2020), and Coptotermes formosanus (Mao and Henderson, 2007). Botanical insecticides quickly affect pests, degrade rapidly, are environmentally friendly and target-specific (Singh and Kaur, 2018;Kamaraj et al, 2018).…”

Laboratory and Greenhouse Evaluation of Melia volkensii Extracts for Potency against African Sweet Potato Weevil, Cylas puncticollis, and Fall Armyworm, Spodoptera frugiperda

“…The antifeedant activity observed could be due to the presence of bitter limonoids that make the diet unpalatable to the insects [2]. Some of the limonoids with insect control potential which have reportedly been isolated from M. volkensii include 1α,3α-diacetylvilasinin, 1-cinnamoyltrichilinin, 1-tigloyltrichilinin, 1-acetyltrichilinin, salannin, 1-detigloyl-1-isobutylsalannin, 2′,3′-dihydrosalannin, ohchinin-3-acetate, nimbolin B, volkensin and toosendanin, among others [9,36]. Previous studies have also reported that most of these insect antifeedant compounds are isolated from M. volkensii fruits [7].…”

“…M. volkensii is a suitable dryland agroforestry tree and is a source of highly praised mahogany timber and termite-resistant poles [6]. M. volkensii seed kernel extracts have shown antifeedant and growth inhibition activity against several insect pests [7][8][9][10]. Insect antifeedant compounds such as salannin, volkensin, 1-tigloyl-trichilinin, 1-cinnamoyltrichilinin and 1-acetyltrichilinin have also been isolated from M. volkensii fruits [7,11].…”

Variation of Morphological Traits and Quality Indices of Micropropagated Melia volkensii Gürke Clones before Field Planting

“…They are also used therapeutically to cure pain and aches [5] and antimicrobial activity [4][5][6][7]. Leaf and fruit extracts are used as insect repellants [8,9]. The tree is termite resistant [2,8,10] and produces hard timber, comparable to mahogany [11,12].…”