Abstract

Onion thrips, Thrips tabaci Lindeman is a cosmopolitan and polyphagous insect pest. Onion thrips cause direct and indirect damage to onion by feeding and ovipositing on leaves of several horticultural crops. Besides causing direct damage to its host plants, T. tabaci has been known as an asymptomatic transmitter of plant pathogens such as tomato spotted wilt virus (TSWV), iris yellow spot virus (IYSV) and tomato yellow ring virus (TYRV). These cause reduction of yield and decrease the market value of the crop. Several synthetic insecticides are used to control the population of onion thrips. However, these insecticides cause pesticide resistance, elimination of non-target species and environmental pollution. To solve the side effects of insecticides, it should be replaced by environmentally friendly pest management alternatives and for this, the use of plant-based pesticides is the best alternative because they do not have residue problems, negative effects on beneficial insects and do not cause air and water quality problems in the environment. Several plants have been investigated which contain bioactive compounds with a variety of biological modes of actions against onion thrips such as repellent, feeding deterrent, anti-ovipositional, fecundity deterrent and metamorphosis inhibition.

Key words: Botanical plants, integrated pest management (IPM), onion thrips, secondary metabolites, modes of action.