Plant-herbivore interaction of ethylene-insensitive petunias and western flower thrips

The phytohormone ethylene (ET) is a key modulator of different physiological plant processes, including flower death and a cascade of plant defenses against herbivores and/or pathogens. Plants increase their ethylene production to trigger flower death or in response to herbivore and pathogen attack. Ethylene insensitive petunias (etr1-1) were developed to produce longer lasting flowers but the impact of herbivores on these plants is unknown. The current study explores western flower thrips (WFT)- induced ethylene on petunia flowers and compares WFT oviposition on etr1-1 and wild-type petunia flowers. Individual flowers were isolated before anthesis and infested with adult WFT females. Flowers were collected for ET measurement and for evaluation of WFT oviposition five days after anthesis. Overall, etr-1 petunia flowers showed a higher ET production than wild-type flowers. We found that petunia flowers produced more ethylene under the attack of WFT. Also, we found the WFT preferred to oviposit more on etr-1 petunias flowers than on wild-type petunia flowers. These results will help us understand the role of ethylene on plant-insect interaction.