近日,華中農(nóng)業(yè)大學(xué)植物科學(xué)技術(shù)學(xué)院李建洪教授帶領(lǐng)的農(nóng)藥毒理學(xué)與有害生物抗藥性團(tuán)隊(duì)研究成果以“Insecticide susceptibility and mechanism of Spodoptera frugiperda on different host plants”為題在Journal of Agricultural and Food Chemistry上在線發(fā)表。研究團(tuán)隊(duì)利用生物化學(xué)、分子生物學(xué)等多種方法,探究了重大入侵害蟲草地貪夜蛾取食不同寄主植物后殺蟲劑敏感性差異機(jī)制,揭示了寄主植物影響草地貪夜蛾殺蟲劑敏感性的分子機(jī)制。
草地貪夜蛾(Spodoptera frugiperda)是聯(lián)合國糧農(nóng)組織(FAO)全球預(yù)警的遷飛性重大農(nóng)業(yè)害蟲,自2018年12月由緬甸入侵我國云南省后迅速蔓延,對(duì)我國糧食安全生產(chǎn)造成嚴(yán)重威脅。草地貪夜蛾寄主范圍廣泛,根據(jù)寄主植物偏好性不同分為“玉米型”和“水稻型”。盡管早期研究發(fā)現(xiàn)入侵我國的草地貪夜蛾主要為玉米型,但仍有為害水稻和其他農(nóng)作物的現(xiàn)象存在。目前草地貪夜蛾的防控主要依賴于化學(xué)防治,但殺蟲劑大量使用導(dǎo)致的抗藥性問題不容忽視。因此,明確草地貪夜蛾在不同寄主植物上的抗性發(fā)展趨勢(shì)對(duì)草地貪夜蛾的高質(zhì)量防控具有重要意義。
研究人員以田間“玉米型”草地貪夜蛾種群為初始種群,在室內(nèi)條件下分別使用水稻和玉米連續(xù)飼養(yǎng)13代,構(gòu)建了取食水稻(水稻品系)和玉米(玉米品系)的兩個(gè)草地貪夜蛾品系,深入探究了兩個(gè)品系草地貪夜蛾對(duì)常用防治藥劑的敏感性差異機(jī)制。結(jié)果表明連續(xù)用水稻飼養(yǎng)并不能改變草地貪夜蛾的寄主型,但與玉米品系相比,水稻品系對(duì)氯蟲苯甲酰胺、茚蟲威、高效氯氟氰菊酯等防治藥劑的敏感性更高。解毒酶活力測(cè)定結(jié)果表明,水稻品系草地貪夜蛾的解毒酶(P450、EST、GST)活力顯著低于玉米品系,說明殺蟲劑解毒代謝能力的不同是導(dǎo)致藥劑敏感性差異的重要原因。研究人員進(jìn)一步通過RNA-Seq、RNAi等實(shí)驗(yàn)鑒定出一個(gè)介導(dǎo)藥劑敏感性差異的關(guān)鍵P450基因(LOC118271197)。進(jìn)一步基于微生物組測(cè)序、抗生素處理和寄主轉(zhuǎn)換等實(shí)驗(yàn)證實(shí)共生菌在不同寄主草地貪夜蛾殺蟲劑解毒代謝中起重要調(diào)控作用。
該研究表明,盡管“玉米型”草地貪夜蛾具備為害水稻的風(fēng)險(xiǎn),但由于其對(duì)水稻的適應(yīng)性較低,在水稻上對(duì)殺蟲劑的敏感性較高,因此使用化學(xué)殺蟲劑仍能對(duì)其進(jìn)行有效防治。研究結(jié)果為針對(duì)不同寄主作物設(shè)計(jì)草地貪夜蛾防治策略奠定了理論基礎(chǔ)。
植物科學(xué)技術(shù)學(xué)院博士研究生郭志敏和已畢業(yè)博士研究生金若珩為該論文共同第一作者,馬康生副教授為論文通訊作者,李建洪教授、萬虎副教授和何順副教授參與了項(xiàng)目的指導(dǎo)。該研究得到湖北省重點(diǎn)研發(fā)計(jì)劃(2020BBA051)和湖北省科技創(chuàng)新行動(dòng)項(xiàng)目(NYKJ2019011)的資助。
【英文摘要】
Spodoptera frugiperda (J. E. Smith) is a worldwide economically important crop pest. Although the individuals of S. frugiperda that invaded China have been characterized as the corn strain, they also have the ability to damage other crops in China. The physiological and behavioral responses of S. frugiperda to different host plants are poorly understood. In the present study, we investigated the host plant preference, fitness costs, and differences in detoxification gene expression and microbiome composition between two S. frugiperda strains that fed on different crop plant diets. The results showed that S. frugiperda larvae exhibited no obvious preference for corn or rice, but significant suppression of development was observed in the rice-fed strain. In addition, the corn-fed strain showed higher insecticide tolerance and detoxification enzyme activities than the rice-fed strain. Moreover, multiple detoxification genes were upregulated in the corn-fed strain, and microbiome composition variation was observed between the two strains. Together, the results suggest that population-specific plasticity is related to host plant diets in S. frugiperda. These results provide a theoretical basis for the evolution of resistance differences in S. frugiperda and are helpful for designing resistance management strategies for S. frugiperda aimed at different crops.
論文鏈接: https://pubs.acs.org/doi/full/10.1021/acs.jafc.2c04189