Elevated CO2 Altered Rice VOCs Aggravate Population Occurrence of Brown Planthoppers by Improving Host Selection Ability

Abstract

It is predicted that plant volatile organic compounds (VOCs) are affected by the atmospheric CO2 levels rising globally, which further affects the interaction between plants and herbivorous insects, especially the host selection behavior of herbivorous insects. In this study, the effects of elevated CO2 on the host-selection behavior of the brown planthopper (BPH) Nilaparvata lugens, and the emission of VOCs from the healthy and BPH-damaged rice plants were studied simultaneously to make clear the population occurrence of BPH under global climate change. Compared with ambient CO2, elevated CO2 significantly increased the host selection percent of BPH for the healthy (CK) and BPH-damaged rice plants, and the host selection percent of BPH for the BPH-damaged rice plants was significantly higher than that for the healthy rice plants under elevated CO2, which might be regulated by the transcription levels of OBP1, OBP2 and CSP8 in BPH due to the upregulated transcriptional levels of these three genes of BPH under elevated CO2. In addition, we analyzed and quantified the emission of VOCs in rice plants grown under ambient CO2 and elevated CO2 by GS-MS. A total of 36 VOCs from rice plants were identified into eight categories, including alkanes, alkenes, alcohols, aldehydes, ketones, esters, phenols and aromatic hydrocarbons. Elevated CO2 significantly decreased the contents of heptadecane, linalool and limonene from rice plants compared with ambient CO2. Besides, the contents of linalool, phytol, decanal, 1-methyldecalin and 2,6-diphenylphenol from BPH-damaged rice plants under ambient CO2, and undecane, hexadecane, nonanal and 2,6-diphenylphenol from BPH-damaged rice plants under elevated CO2 were all significantly higher than those from healthy rice plants. The percentage composition of phenols was positively correlated with the host selection rate of BPH. Our study indicates that elevated CO2 is beneficial to promote the host selection ability of BPH for rice plants damaged by BPHs due to the changed plant VOCs.

Selection Behavior and OBP-Transcription Response of Western Flower Thrips, Frankliniella occidentalis, to Six Plant VOCs from Kidney Beans

“…In our study, the relative expression levels of LOC113203279 and LOC113205269 were not affected by all treatments, but the transcription level of LOC113214975 was up-regulated universally, and LOC113205302 was significantly down-regulated under all treatments. This indicated that the functions of LOC113214975 and LOC113205302 in olfactory recognition were conservative and critical, although they were different from what has previously been reported [ 29 , 57 , 58 ]. It was more likely that there may be antagonism between LOC113214975 and LOC113205302 .…”

Adult host‐plant preference and larval performance in an oligophagous insect (Chnootriba elaterii)

“…In herbivorous insects, the main behaviours affecting fitness, such as feeding, mating, and oviposition, are influenced by plant‐related cues (Awmack & Leather, 2002; Carrasco et al, 2015; Städler et al, 2002; Wang et al, 2022). The success of an oligophagous herbivorous insect, in particular, depends on its ability to locate the best host plant, use its nutrients and cope with its defence (Bernays & Chapman, 1994; Fernandez & Hilker, 2007).…”