Sun Yong-Duo, Wallis Christopher M, Krugner Rodrigo, Yokomi Raymond
United States Department of Agriculture, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, Parlier, CA 93648, USA.
Plants (Basel). 2025 Jan 20;14(2):288. doi: 10.3390/plants14020288.
Plant viruses have been known to alter host metabolites that influence the attraction of insect vectors. Our study investigated whether (CYVCV) infection influences vector attractiveness, focusing on the citrus whitefly, (Ashmead). Free choice assays showed that citrus whiteflies exhibited a preference for settling on CYVCV-infected lemon plants versus healthy control plants. Using chromatography techniques, we found that the levels of sugars were similar in leaves and stems of both plant groups, while the contents of several amino acids in leaf or stem samples and non-volatile phenolic compounds in the leaf samples of CYVCV-infected and healthy plants differ drastically. In addition, volatile terpenes/terpenoids decreased significantly in virus-infected plants compared to healthy controls. Several of the identified volatile compounds such as α-phellandrene, α-terpinolene, p-cymene, linalool, and citral are known for their whitefly repellent properties. Further Y-tube olfactometer bioassays revealed that emissions of volatile organic compounds (VOCs) from infected plants attracted more citrus whiteflies, but not alate spirea aphids, Patch, than those from healthy plants, suggesting that the VOCs released from CYVCV-infected lemon plants may specifically affect citrus whiteflies. Therefore, we suggest that, in addition to the visual cue of yellow vein symptoms, the preference of citrus whiteflies that settled on CYVCV-infected lemon plants was attributed to a reduction in the levels of repellent volatile compounds.
已知植物病毒会改变宿主代谢产物，进而影响昆虫传毒介体的吸引力。我们的研究调查了柑橘黄脉病毒（CYVCV）感染是否会影响传毒介体的吸引力，重点研究对象是柑橘粉虱[Dialeurodes citri (Ashmead)]。自由选择试验表明，相较于健康对照植株，柑橘粉虱更倾向于在感染CYVCV的柠檬植株上栖息。通过色谱技术，我们发现两组植株叶片和茎中的糖分水平相似，而CYVCV感染植株与健康植株的叶片或茎样本中的几种氨基酸含量以及叶片样本中的非挥发性酚类化合物含量差异显著。此外，与健康对照相比，病毒感染植株中的挥发性萜类/类萜显著减少。已鉴定出的几种挥发性化合物，如α-水芹烯、α-萜品烯、对伞花烃、芳樟醇和柠檬醛，都具有驱避粉虱的特性。进一步的Y型嗅觉仪生物测定表明，感染植株释放的挥发性有机化合物（VOCs）比健康植株吸引了更多的柑橘粉虱，但对绣线菊蚜（Aphis spiraecola Patch）无此影响，这表明CYVCV感染的柠檬植株释放的VOCs可能对柑橘粉虱有特异性影响。因此，我们认为，除了黄脉症状这一视觉线索外，柑橘粉虱倾向于在感染CYVCV的柠檬植株上栖息，是由于驱避性挥发性化合物水平降低所致。
