Naturalne i syntetyczne antyfidanty owadów : cz.1.

Insect antifeedants are chemicals which inhibit feeding, but do not kill the insect directly, the insect often remaining near the antifeedant source and possibly dying through starvation. Many antifeedants have been found in plants, being a part of their protective system against its predators. Antifeedants, unlike pesticides, are often selectively toxic towards some insect species, whereas they are not harmful to the other ones and to mammals. As crop protection currently relies upon the use of broad spectrum of pesticides, friendlier to environment antifeedants are focus of recent research. Their current use is limited, as it is difficult to obtain them in useful quantities. Moreover, most of them are highly complexed molecules, which are not readily synthesised. The aim of researchers is to obtain a synthetic antifeedant of a simple structure, which retain the potency of natural products and fulfil synthetic requirements to be of practical use. The mono- and sesquiterpenoid natural and synthetic antifeedants are presented here. There are few natural monoterpenoid compounds of deterrent activity, whereas there are many numerous groups of sesquiterpene ones. The most known among sesquiterpenes are drimanes, isolated from bark of Drimys species, containing bicyclofarnesane skeleton - active antifeedants against aphids. The second large group are compounds isolated from mushrooms of Lactarius species, divided into marasmanes and lactaranes, active towards stored products pests. Many synthetic derivatives of natural antifeedants have been investigated so as to find correlation between structure and activity. Biological data showed that there is no single functional group responsible for deterrent activity. Even a small structure modification in different parts of a molecule may reduce the activity drastically. However, it is significant, that en-dialdehyde function, as well as g- or d-lactone ring are often present in active feeding deterrents. Sesquiterpene lactones, isolated from wide range of plants, are a very large group of insect antifeedants. Mono- and sesquiterpene lactones are the most promising compounds in search of new, synthetic insect antifeedants. Several synthetic terpenoid lactones of twelve carbon atoms, active deterrents against stored grain pests, are also presented.