Western flower thrips (Frankliniella occidentalis) and the associated TSWV transmission represent one of the largest single pest and disease problems in horticulure worldwide. This is due to the changing cultivation practices of ornamental and vegetable crops towards large scale, automated, (semi)closed cultivation. The only durable solution is the introduction of genetic resistance into crops. Such crops will be very competitive in the international markets, and this project will generate the tools to develop such crops.
We aim to characterize the biochemical and genetic basis of existing resistance to thrips and TSWV transmission in cultivated and wild chrysanthemum (pyrethrum) . For this we elucidate the pathway leading to both high jasmonate and pyrethrin production in glandular trichomes of these plants. Jasmmonate is a universal wound hormone inducing resistance to insects in all plants bases on the induction of many different defence genes. Pyrewthins take jasmonate as a substrate to form the most potent organic insecticide known today. Thus, this project is developing knowledge around both the most generic and the most potent botanical insect control agents known to date. The project focuses on the control of thrips and virus transmission, but the resulting principles will offer generic, durable solutions also for many other pest-plant problems which will be of additional benefit to the aims of TTI-GG.