natural-products-in-plant-pest-management

Control of Mycotoxins and Mycotoxigenic Fungi 31oxidant properties that increase lipid peroxidation and, consequently, fumonisinproduction (López et al., 2004).Essential oils of O. basilicum and O. gratissimum have been demonstratedto reduce the incidence of F. verticillioides in maize, and totally inhibited fungalgrowth at concentrations of 6.4 and 4.8 μl/g, respectively, although at the4.8 μl/g dose they did not affect fumonisin production. On the other hand,oil of neem seeds has been shown to accelerate the growth of F. verticillioideson maize grains (Fandohan et al., 2004).WheatTo control A. flavus development on wheat, the essential oils of C. citratus,O. gratissimum, Zingiber cassumunar and Caesulia axillaris have been assayed.The oils of Caesulia citratus and Caesulia axillaris showed fungistatic activity,indicating their in vivo applicability as herbal fumigants (Dubey et al., 2000).In the same way, vapours of the essential oil of Caesulia axillaris (1300μg/g, v/v) have been shown to control A. flavus, A. niger, A. fumigatus, A.sulphureus, Rhizopus spp., Mucor spp., Curvularia spp., Penicillium oxalicumand Absidia spp. during 12 months of storage. The essential oil of Menthaarvensis (600 μg/g, v/v) showed similar results. These oils were also effectivein controlling the insect pests Sitophilus oryzae (Varma and Dubey, 2001). Similarly,the practical applicability of essential oil from leaves of wormseed(Chenopodium ambrosioides) as a fumigant for protecting stored wheat hasbeen assayed. A concentration of 100 μg/ml applied as a fumigant was ableto control A. flavus, A. niger, A. parasiticus, A. terreus, A. candidus and P.citrinum during 12 months of storage (Kumar et al., 2007).The essential oils of thyme and cinnamon (≤500 μg/g), Calendula officinalis(marigold) (≤2000 μg/g), Mentha viridis (spearmint), basil and Achilleafragantissima (quyssum) (≤3000 μg/g) completely inhibited A. flavus, A. parasiticus,A. ochraceus and F. moniliforme on wheat grains. Caraway oil (Carumcarvi) was inhibitory at 2000 μg/g against A. flavus and A. parasiticus and at3000 μg/g against A. ochraceus and F. moniliforme. Anise oil completely inhibitedthe four fungi at ≤500 μg/g. Worse results were obtained with essentialoils of chamomile (Matricaria chamomilla) and hazanbul (Achillea millefalium)(Soliman and Badeaa, 2002).Resveratrol, an extract of grape skin, has been demonstrated to be effectivein controlling the ochratoxigenic fungi P. verrucosum and A. westerdijkiaeon naturally contaminated wheat (Aldred et al., 2008). Total populations offungi were significantly reduced by the presence of this compound, often byabout 1–3 log colony forming units (CFU), but CFUs of the mycotoxigenicinoculated fungi were reduced only about 1–2 logs. In experiments developedat different water activities (0.995–0.80 a wrange) and temperatures (15–25°C)during a 28-day period of storage, grain treated with resveratrol (200 μg/g)had significantly less ochratoxin A (OTA) than the untreated controls. OTAcontamination was reduced by >60% in most of the treatment conditions.Extracts of Argyreia speciosa and Oenothera biennis have also beenassayed. Hexadecanyl p-hydroxycinnamate and scopoletin isolated from