Antifeedant and Insecticidal Properties

CARPINELLA, M.C., DEFAGO, M.T., VALLADARES, G., PALACIOS, S.M., Antifeedant and insecticide properties of a limonoid from Melia azedarach (Meliaceae) with potential use for pest management, J. Agric. Food Chem., 2003, 51,369-374. 

Lignans together with other allelochemicals may play a role in synergising antifeedant or insecticidal properties. Sesamin and asirin showed synergistic properties with pyrethrum insecticides [2], Pinoresinol, bis-epipinoresinol, the hemicetal and the diacid isolated from the Brazilian... 

In the course of these research programmes, many characteristic bioactive compounds have been reported. Polyester sesquiterpenes and pyridine-sesquiterpene alkaloids with insect antifeedant or insecticidal properties have been isolated from some species and recently sesquiterpene pyridine alkaloids with immunosuppressive or antitumoral activities have also been described. Diterpene triepoxides with potent antileukemic and immunosupressive activities and triterpenoid quinonemethides, named as celastroloids , with antibiotic and cytostatic activities, have been isolated from species of the Celastraceae family. 

So, the scientific community will be reluctant to consider the remarkable synergistic suites of compounds that have evolved naturally in plants. But we really cannot afford to ignore these. For nature favors synergies among beneficial, plant-protective compounds within a plant species (with antibacterial, antifeedant, antifungal, antiviral, and insecticidal properties), and selects against antagonisms. 

In the course of these research programmes, cytotoxic quinones, polyester sesquiterpenes and pyridine-sesquiterpene alkaloids with antifeedant and/or insecticidal properties have been isolated from Latin American species, in particular those of the Maytenus genus which is extensively used by rural communities and tribes in the Andes and the Amazon basin. Recently some sesquiterpene alkaloids with immunosuppressive activity and sesquiterpenes with antitumoral activity have also been described [3]. 

Antifeedant Compounds Insecticidal and Nematicidal Activity Diterpenes with Juvenile Hormone Activity Diterpenes That Prevent Reproduction in Insects Trail-Marking Pheromones Diterpenes from Marine Plants Sweeteners Medicinal Properties Antitumor Compounds Sesterterpenes Biosynthesis Biological Activity References... 

Certain other meliaceous seed extracts were equally active to azadirachtin in bioassays (Mikolajczak and Reed, 1987). TTiose of Aglaia cordata were more potent than extracts of neem toward larvae of Spodoptera frugiperda (Mikolajczak et al., 1989). A limonoid compound from Carapa procera had antifeedant activity comparable to that of azadirachtin, but much weaker insecticidal properties. This compound, methyl 3 3-isobutyryloxy-l-oxomeliac-8(30)-enate (42), also was found in Khaya senegalensis and K. nyasica (Mikolajczak et al., 1988). 

Numerous plant alkaloids with antiherbivore properties are classified according to their mode of action (e.g., toxins, antifeedants, antidigestive proteins, etc.) and have been used in agriculture to control insect pests. The pyridine alkaloid nicotine is one of the best-studied putative plant resistance traits. Because it can interact with the acetylcholine receptors in the nervous systems of animals, nicotine is extremely toxic to most herbivores and, consequently, was one of the first insecticides used to control pests in agriculture. Evidence for the resistance value of nicotine arises from... 

Synthetic pyrethoids. These chemicals have a particularly high insecticidal power whilst generally being safe to hnmans and farm animals. They are efficient contact insecticides with a rapid knockdown action and some are thonght to act as antifeedants. These properties are seen as being valuable in the chemical control of plant viruses by controlling the insect vectors, e.g. cypermethrin and A-cyhalothrim... 

We have examined a variety of plants, chosen for their traditional medicinal or insect control uses, for insecticidal and insect antifeedant properties. Our test insects are crop pests such as the tobacco cutworm Spodoptera litura, medically important insects (e.g the yellow fever mosquito Aedes aegyptii) or wood-destroying organisms such as the termite Reticulitermes speratus. 

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