Olfactory Response of Plutella xylostella (Lepidoptera: Yponomeutidae) Adults to Refugia Plant

Abstract

Selection of refugia plants is an important step when engineering the agroecological system. The refugia plants can be repellent or attractant to insect pests and in many species the role of each plant can be studied using the olfactory responses of the insect to volatile chemical cues emitted by the plant. The objective of this study was to determine the olfactory response of Plutella xylostella (Lepidoptera: Yponomeutidae) adults to several refugia plant candidates. Y-tube olfactometer tests were used to determine responses of P. xylostella to candidate plant species including: Ageratum conyzoides, Galinsoga parviflora, Synedrella nodiflora, Sphagneticola trilobata, Brassica rapa, Rorippa indica, Arachis pintoi, Ocimum basilicum, Apium graveolens, and Portulaca oleracea. Olfactory choice tests were conducted to compare preferences of insect. The results showed that R. indica, G. parviflora, and S. trilobata flowers attracted P. xylostella. R. indica and B. rapa leaves had high attractiveness for P. xylostella adults. At the same time, the A. graveolens, A. conyzoides, and O. basilicum leaves showed potential repellency. The conclusions of this study are R. indica and B. rapa have potential for use as trap crops, while A. graveolens, O. basilicum, and A. conyzoides have potential as repellent plants. Further study is necessary to test the olfactory response of P. xylostella’s natural enemies to these refugia plants.