陳茜,劉英杰,2,董勇浩,劉金燕,李煒,徐蓬軍,臧云,任廣偉
黃瓜花葉病毒侵染煙草對(duì)煙蚜生長發(fā)育、取食和選擇行為的影響
陳茜1,劉英杰1,2,董勇浩1,劉金燕1,李煒1,徐蓬軍1,臧云1,任廣偉1
1中國農(nóng)業(yè)科學(xué)院煙草研究所,山東青島 266101;2中國煙草總公司職工進(jìn)修學(xué)院,鄭州 450008
【】探明黃瓜花葉病毒(cucumber mosaic virus,CMV)侵染煙草對(duì)煙蚜()生長發(fā)育和行為的影響,研究CMV 2b基因在煙蚜與CMV互作中的作用。供試寄主植物為健康煙草和CMV侵染、CMV 2b基因缺失突變體(CMVΔ2b)侵染煙草,利用Y型嗅覺儀測(cè)定煙蚜對(duì)不同煙草寄主的選擇趨向;利用刺吸電位圖譜(electrical penetration graph,EPG)監(jiān)測(cè)煙蚜取食行為,并結(jié)合寄主植物內(nèi)總糖和游離氨基酸含量分析CMV侵染對(duì)煙蚜取食行為的影響;通過單株微蟲籠記錄蚜蟲生命參數(shù)并分析CMV侵染煙草對(duì)煙蚜生長發(fā)育和繁殖的影響。CMV侵染煙草葉片中總糖含量顯著低于健康煙草,而游離氨基酸的含量顯著高于健康煙草和CMVΔ2b侵染煙草。CMVΔ2b侵染煙草中的蘇氨酸、谷氨酸、甘氨酸、酪氨酸、組氨酸、精氨酸和脯氨酸含量顯著高于其他處理煙草,纈氨酸和賴氨酸含量顯著高于健康煙草;而CMV侵染煙草中的天冬氨酸含量顯著低于其他處理煙草,其胱氨酸含量顯著高于CMVΔ2b侵染煙草。相較于CMV侵染煙草,煙蚜對(duì)健康煙草和CMVΔ2b侵染煙草有著更強(qiáng)的選擇趨向,而煙蚜對(duì)健康煙草與CMVΔ2b侵染煙草的選擇行為無顯著差異。CMV侵染煙草對(duì)煙蚜的生長發(fā)育和取食行為產(chǎn)生不利影響。煙蚜在CMV侵染煙草上的刺探行為(pd波)發(fā)生次數(shù)最多,韌皮部取食(E2波)的持續(xù)時(shí)間最短,且木質(zhì)部吸食(G波)的發(fā)生頻率顯著高于健康煙草和CMVΔ2b侵染煙草,表明CMV侵染煙草不適宜煙蚜取食。煙蚜的生長特性試驗(yàn)表明CMV侵染煙草顯著延長了煙蚜的若蚜歷期,提高了2齡若蚜的死亡率,縮短了煙蚜的壽命,顯著降低了煙蚜繁殖力。CMV侵染煙草上煙蚜的內(nèi)稟增長率()和周限增長率()均顯著低于健康煙草和CMVΔ2b侵染煙草,CMV的侵染不利于煙蚜種群的增長。CMV侵染改變了煙草營養(yǎng)物質(zhì)組成,CMV 2b基因的存在增加了煙蚜刺探頻率,減少了煙蚜在煙株上的韌皮部取食;CMV侵染導(dǎo)致煙蚜若蚜歷期延長、死亡率增加,煙蚜壽命和繁殖力均顯著降低;CMV侵染降低了煙蚜的寄主適合度,促使蚜蟲向新寄主植物轉(zhuǎn)移,從而促進(jìn)了病毒的擴(kuò)散傳播。
黃瓜花葉病毒;煙蚜;煙草;生長發(fā)育;取食行為;寄主選擇
【研究意義】黃瓜花葉病毒(cucumber mosaic virus,CMV)寄主范圍廣,可危害茄科、葫蘆科、十字花科等多種農(nóng)作物,在世界范圍內(nèi)廣泛傳播流行。由CMV造成的病害在我國多個(gè)煙區(qū)廣泛分布,常導(dǎo)致煙草產(chǎn)量和品質(zhì)損失嚴(yán)重[1]。CMV可以通過蚜蟲以非持久性方式進(jìn)行傳播,蚜蟲的遷飛與CMV病害的傳播與流行密切相關(guān)。感染CMV的寄主植株的生理生化變化可影響介體蚜蟲的生物學(xué)特性,CMV的2b基因在蚜蟲傳播CMV的過程中發(fā)揮重要的作用[2-3]。探明寄主植物-介體蚜蟲-CMV的互作關(guān)系,明確CMV 2b基因在病毒傳播中的作用,對(duì)制定科學(xué)有效的CMV防控策略具有重要意義?!厩叭搜芯窟M(jìn)展】植物病毒可以通過改變寄主植物的葉片形態(tài)、代謝特征和植物對(duì)生物、非生物脅迫的反應(yīng)來增強(qiáng)自身適應(yīng)性,并可能會(huì)干擾介體昆蟲與植物相互作用的所有階段以增強(qiáng)病毒的傳播[4-5]。在介體昆蟲的寄主定位選擇階段,病毒侵染可改變寄主植物的生理生化特性,如葉片顏色、揮發(fā)性物質(zhì)的釋放等,從而間接改變介體蚜蟲的行為,影響植物對(duì)介體蚜蟲的吸引力和偏好性[6]。而在介體昆蟲成功定位寄主后,植物病毒還可通過改變寄主植物的營養(yǎng)物質(zhì)、次生代謝產(chǎn)物等方式改變蚜蟲在感病植物上的取食行為和生長發(fā)育[7-8]。例如番木瓜環(huán)斑病毒(papaya ringspot virus,PRSV)侵染西葫蘆后,感病葉片內(nèi)的必需氨基酸蘇氨酸、精氨酸和賴氨酸,非必需氨基酸甘氨酸和半胱氨酸以及可溶性碳水化合物濃度,相較于健康植株均顯著提高;在PRSV侵染植株上取食的瓜蚜()繁殖力、壽命及種群內(nèi)稟增長率等均較健康植株顯著提高[9]。不同病毒侵染寄主植物對(duì)其介體昆蟲也表現(xiàn)出不同的影響,如蕪菁花葉病毒(turnip mosaic virus,TuMV)和馬鈴薯Y病毒(potato virus Y,PVY)侵染寄主后均表現(xiàn)出對(duì)介體昆蟲有利的影響[10-11],但LI等[12]研究發(fā)現(xiàn),大豆花葉病毒(soybean mosaic virus,SMV)侵染大豆后,在大豆植株上取食的大豆蚜()各齡期的蟲體質(zhì)量都顯著降低,發(fā)育歷期顯著延長,生殖力降低,種群增長速率降低。此外,病毒的擴(kuò)散傳播也與介體昆蟲的取食行為密切相關(guān)。介體昆蟲對(duì)植物病毒的獲取和傳播發(fā)生在介體昆蟲的取食過程中,其在感病植株和健康植株葉片上的取食行為也存在著差異[13-15]。在持久性病毒馬鈴薯卷葉病毒(potato leafroll virus,PLRV)侵染的馬鈴薯葉片上,蚜蟲口針刺探過程中E1波的出現(xiàn)顯著提前,持續(xù)刺吸時(shí)間增長,即帶毒葉片更利于蚜蟲在寄主韌皮部刺吸,從而有利于蚜蟲的獲毒[16]。介體對(duì)非持久性病毒的傳毒效率與pd波的數(shù)量呈正相關(guān)性,與蚜蟲口針最后一次離開細(xì)胞到停止刺探的時(shí)間呈負(fù)相關(guān)性[17]。在非持久性病毒PVY侵染的煙草葉片上取食的煙蚜(),與健康煙草上的煙蚜相比,其在感病葉片上的刺探次數(shù)增加、刺探頻率提高,且每次刺探發(fā)生持續(xù)時(shí)間較短,有利于蚜蟲口針和病毒粒子的結(jié)合[18-19]。GUO等[2]研究發(fā)現(xiàn),CMV 2b基因參與病毒與寄主植物和煙蚜的互作,它可通過改變寄主植物的生理變化來調(diào)控?zé)熝恋娜∈澈瓦x擇行為,CMV的侵染可導(dǎo)致寄主植物組織中產(chǎn)生更高濃度的活性氧(H2O2),蚜蟲在CMV侵染的植物上比在CMV 2b基因缺失突變體(CMVΔ2b)侵染的植物上的帶毒量更大,蚜蟲也更頻繁地離開最初的取食部位,從而促進(jìn)病毒傳播。【本研究切入點(diǎn)】CMV、寄主植物與介體蚜蟲的互作關(guān)系已有大量研究,其中CMV侵染煙草對(duì)介體蚜蟲影響的相關(guān)研究主要集中在繁殖特性和寄主選擇行為等方面,較少關(guān)注煙草營養(yǎng)成分的變化,CMV、CMVΔ2b侵染煙草后對(duì)介體煙蚜的生長發(fā)育、取食行為和寄主選擇行為有何影響尚未明確?!緮M解決的關(guān)鍵問題】通過構(gòu)建CMV 2b基因缺失突變體,研究CMV侵染煙草對(duì)介體煙蚜生長發(fā)育、選擇行為和取食行為的影響,并結(jié)合寄主植物內(nèi)總糖和游離氨基酸含量變化,分析CMV 2b基因在互作關(guān)系中的作用,以期為黃瓜花葉病毒病的防控提供理論依據(jù)。
試驗(yàn)于2019年在中國農(nóng)業(yè)科學(xué)院煙草研究所煙草病蟲害監(jiān)測(cè)與綜合治理重點(diǎn)實(shí)驗(yàn)室完成。
供試?yán)ハx:煙蚜由中國農(nóng)業(yè)科學(xué)院煙草研究所植物保護(hù)研究中心提供,挑選來自同一母體的若蚜,用健康煙苗在人工氣候箱中繁殖多代。飼養(yǎng)條件為光周期14L﹕10D、溫度(25±1)℃、相對(duì)濕度65%±5%。
供試寄主:烤煙品種K326(‘K326’),在人工氣候室中將煙苗培養(yǎng)至6—7葉期備用。培養(yǎng)條件同上。
供試病毒:CMV侵染性克隆質(zhì)粒pCB301-Fny1、pCB301-Fny2、pCB301-Fny3由南京農(nóng)業(yè)大學(xué)植物保護(hù)學(xué)院陶小榮教授提供[20]。該侵染性克隆是在植物表達(dá)載體pCB301-2x35S-HDVRZ-NOS(NCBI載體序列登錄號(hào):JN029690)的基礎(chǔ)上構(gòu)建的CMV-Fny 3條基因組的侵染性克隆。對(duì)pCB301-Fny2上與2a非重疊部分的CMV 2b基因(91 bp)缺失處理,構(gòu)建CMVΔ2b突變體,由TaKaRa公司完成,獲得pCB301-Fny2-2b- del質(zhì)粒及菌種。通過農(nóng)桿菌轉(zhuǎn)染法獲得CMV、CMVΔ2b毒源。缺失的序列片段為:GGCCTCTCGTTT AGAGTTATCGGCGGAAGACCATGATTTTGACGATACAGATTGGTTCGCCGGTAACGAATGGGCGGAAGGTGCTTTCTGA。
1.2.1 摩擦接種 取毒源煙株中部葉片,電子天平稱重,在滅菌的研缽中將煙草葉片充分研磨,按1﹕10配比加入PBS緩沖液(pH 7.2),于冰上迅速研磨成漿液,過濾掉葉片殘?jiān)羧∏逡?。選取待接種煙株下部對(duì)稱位第二、三片葉,在葉面傾撒一層石英砂,移液槍吸取200 μL接種液均勻點(diǎn)在葉面上,使用滅菌棉棒沿葉脈走向輕輕摩擦接種。
1.2.2 煙草葉片中總糖含量檢測(cè) 取CMV、CMVΔ2b接毒和模擬接毒后第15天煙草植株,收集除接毒葉片外的全株其余葉片,沖洗葉片表面污物后用電子天平稱量計(jì)鮮重(fresh weight,F(xiàn)W),將葉片置于液氮中充分研磨后轉(zhuǎn)移至冷凍干燥機(jī)中凍干處理,計(jì)干重(dry weight,DW)。取凍干后的煙葉樣品利用蒽酮比色法測(cè)定總糖含量,測(cè)定方法參照植物總糖含量試劑盒(品牌:cominbio,貨號(hào):ZT-2-Y)說明書。CMV、CMVΔ2b接毒和模擬接毒處理各設(shè)3組生物學(xué)重復(fù)。
1.2.3 煙草葉片中游離氨基酸含量檢測(cè) 樣品的獲取方法同1.2.2。準(zhǔn)確稱取均勻性一致的試樣(精確到0.0001 g)于50 mL離心管中,加入20 mL 0.01 mol·L-1的鹽酸,渦旋混勻,超聲提取30 min,冷卻定容過膜后使用高速氨基酸分析儀(日立L-8900)上機(jī)檢測(cè),對(duì)不同寄主植物葉片內(nèi)18種氨基酸含量進(jìn)行檢測(cè)。CMV、CMVΔ2b接毒和模擬接毒處理各設(shè)3組生物學(xué)重復(fù)。
1.2.4 煙蚜的寄主選擇行為測(cè)試 煙蚜對(duì)不同處理
煙株的選擇性試驗(yàn)通過Y型嗅覺儀進(jìn)行,供試煙株分別為侵染15 d的CMV、CMVΔ2b侵染煙株和同時(shí)期健康煙株,供試煙蚜為2—3日齡成蚜。Y型管進(jìn)氣口處分別接入兩個(gè)空氣流量計(jì)用于控制空氣流速(150—200 mL·min-1),試驗(yàn)時(shí)打開日光燈保證光源均勻。試驗(yàn)時(shí)在Y型管出氣口處放置1頭成蚜(饑餓處理1 h),觀察記錄其選擇行為,10 min內(nèi)煙蚜進(jìn)入某一氣味臂約1/2處開始計(jì)時(shí)且停留30 s以上,則記為供試蚜蟲對(duì)該側(cè)煙株有選擇行為;若未進(jìn)入任意一臂或者停留時(shí)間未達(dá)30 s就返回出氣口方向,則記為無選擇,每測(cè)試5頭蚜蟲交換氣味管位置。每組試驗(yàn)設(shè)100次重復(fù)。
1.2.5 煙草上的煙蚜取食行為測(cè)試 利用刺吸電位儀DC-EPG(Giga-8)(荷蘭,瓦赫寧根大學(xué)及研究中心)監(jiān)測(cè)煙蚜在不同處理煙株上的取食行為。寄主植物分別為CMV、CMVΔ2b接毒和模擬接毒后第15天的煙草。取大小一致的煙蚜成蟲,將昆蟲電極用導(dǎo)電銀膠粘于煙蚜前胸背板,饑餓處理1 h后分別放在寄主植物心葉下一片葉的葉背面,植物電極插入土壤中使其形成回路,關(guān)閉法拉第電籠,持續(xù)監(jiān)測(cè)6 h。各處理重復(fù)試驗(yàn)25次,選取有效重復(fù)15次以上進(jìn)行數(shù)據(jù)統(tǒng)計(jì)分析。
按照ALVAREZ等的方法對(duì)蚜蟲的EPG波形進(jìn)行解析,通過EPG Stylet+a軟件對(duì)煙蚜的取食波形進(jìn)行判定并標(biāo)記[16,21],分析np、C、pd、E1、E2、G波及EPG測(cè)試過程中的其他相關(guān)取食行為參數(shù)。
1.2.6 煙草上的煙蚜生長發(fā)育記錄 參考臧連生等[22]的方法,用直徑為3.5 cm的培養(yǎng)皿和小夾子制作蚜蟲微蟲籠,用于單頭煙蚜的單株培養(yǎng)。用干凈毛筆將成蚜輕輕接到CMV侵染10 d的煙株心葉下兩片葉的葉背面,待24 h后移除成蚜和多余若蚜,僅保留1頭新生若蚜,用微蟲籠夾住葉片固定蚜蟲活動(dòng)范圍,編號(hào)后進(jìn)行蚜蟲生長發(fā)育記錄。若蚜?xí)r期,每天上午和下午分分別記錄煙蚜存活情況和齡期,并及時(shí)清除蛻皮,待其羽化為成蚜后,每天上午調(diào)查其存活情況及產(chǎn)蚜量,每次調(diào)查時(shí)移除新生若蚜,持續(xù)記錄直至成蚜全部死亡。共設(shè)置CMV、CMVΔ2b侵染和健康煙草3個(gè)處理,重復(fù)50次。
利用IBM SPSS Statistics 23 軟件進(jìn)行數(shù)據(jù)統(tǒng)計(jì)分析。采用LSD法比較不同處理間煙蚜的EPG參數(shù)、煙草葉片中總糖含量和氨基酸含量的差異顯著性,采用卡方檢驗(yàn)比較不同處理間煙蚜的選擇行為差異。利用Twosex-MSchart軟件[23-24],通過Bootstrap程序(Bootstrap次數(shù)為100 000)分別計(jì)算不同寄主煙株上煙蚜生命表參數(shù)和種群參數(shù)的方差和標(biāo)準(zhǔn)誤,分析各處理之間的差異顯著性。
健康、CMV侵染和CMVΔ2b侵染的煙草葉片中總糖含量分別為229.88、144.01、198.05 mg·g-1,健康煙草中的總糖含量顯著高于CMV和 CMVΔ2b侵染煙草(<0.05);健康、CMV侵染和CMVΔ2b侵染的煙草葉片中游離氨基酸含量分別為6.14、12.35、5.48 mg·g-1,CMV侵染煙草中的游離氨基酸含量顯著高于健康煙草和CMVΔ2b侵染煙草(<0.05)(圖1)。
圖中數(shù)據(jù)為平均值±標(biāo)準(zhǔn)誤。柱上不同小寫字母表示該參數(shù)經(jīng)單因素方差分析法檢驗(yàn)結(jié)果差異顯著(P<0.05,LSD)
不同處理煙草體內(nèi)18種游離氨基酸含量也具有一定差異(表1)。CMVΔ2b侵染煙草中的蘇氨酸、谷氨酸、甘氨酸、酪氨酸、組氨酸、精氨酸和脯氨酸含量顯著高于其他處理煙草,纈氨酸和賴氨酸含量顯著高于健康煙草,而CMV侵染煙草中的天冬氨酸含量顯著低于其他處理煙草,胱氨酸含量顯著高于CMVΔ2b侵染煙草。
健康煙草與CMV侵染煙草相比,煙蚜對(duì)健康煙草有更強(qiáng)的選擇偏好(2=30.224,<0.001);CMV侵染煙草與CMVΔ2b侵染煙草相比,煙蚜對(duì)CMVΔ2b侵染煙草具有更強(qiáng)的選擇偏好(2=21.062,<0.001);煙蚜對(duì)健康煙草與CMVΔ2b侵染煙草的選擇行為無顯著差異(2=0.276,=0.599)(圖2)。
采用EPG技術(shù)對(duì)煙蚜在不同寄主煙草上的取食行為進(jìn)行了監(jiān)測(cè),選取包含np、C、pd、E1、E2、G波共6個(gè)波形在內(nèi)的19個(gè)相關(guān)參數(shù)進(jìn)行統(tǒng)計(jì)分析(表2)。
健康、CMV侵染和CMVΔ2b侵染煙草的3個(gè)處理中,煙蚜的第一次刺探發(fā)生時(shí)間、非刺探波(np波)次數(shù)和持續(xù)時(shí)間均無顯著差異。在煙蚜刺探路徑階段,煙蚜在CMV侵染煙草上的刺探發(fā)生次數(shù)(pd波)顯著高于CMVΔ2b侵染煙草(表2,參數(shù)3)。煙蚜的韌皮部取食階段,煙蚜在CMVΔ2b侵染煙草上韌皮部的取食時(shí)長(E2波)顯著高于CMV侵染煙草(表2,參數(shù)12和13)。煙蚜在3種寄主煙草上均有木質(zhì)部吸食的發(fā)生(G波),其中煙蚜在CMV侵染煙草上木質(zhì)部吸食的發(fā)生概率顯著高于其他寄主煙株(表2,參數(shù)17)。
由圖3可知,CMV侵染煙草提高了煙蚜的若蚜死亡率,2齡若蚜死亡率及若蚜期死亡率均顯著高于健康煙草和CMVΔ2b侵染煙草(<0.05)。1、3、4齡若蚜死亡率在CMV、CMVΔ2b侵染煙草和健康煙草3個(gè)處理間無顯著差異。
表1 不同煙草葉片中游離氨基酸含量
表中數(shù)據(jù)為平均值±標(biāo)準(zhǔn)誤。同一行內(nèi)不同小寫字母表示該參數(shù)經(jīng)單因素方差分析法檢驗(yàn)結(jié)果差異顯著(<0.05)。表2同
Data in the table are mean±SE. Different lowercase letters in the same row indicate the parameter has a significant difference at 0.05 level (LSD test after one-way ANOVA). The same as Table 2
**表示煙蚜對(duì)不同寄主煙株的選擇行為有極顯著差異(P<0.01,卡方檢驗(yàn))
表2 不同煙草寄主上的煙蚜取食EPG參數(shù)
由表3、表4可知,各處理煙草上煙蚜4齡若蚜發(fā)育歷期、成蟲期、成蟲繁殖前期和繁殖期均無顯著差異,但CMV侵染煙草上煙蚜的1齡、2齡、3齡若蚜歷期、若蚜歷期、總繁殖前期均顯著高于健康煙草和CMVΔ2b侵染煙草,CMV侵染煙草上煙蚜的壽命顯著低于健康煙草和CMVΔ2b侵染煙草(<0.05)。健康煙草上煙蚜的繁殖力顯著高于CMV侵染煙草(<0.05),健康煙草與CMVΔ2b侵染煙草上煙蚜的繁殖力無顯著差異。
由表5可知,煙蚜在CMV、CMVΔ2b侵染煙草和健康煙草上的種群參數(shù)亦有一定差異。其中,煙蚜的平均世代周期()無顯著差異,但健康煙草上煙蚜的內(nèi)稟增長率()和周限增長率()均顯著高于CMV和CMVΔ2b侵染煙草(<0.05)。健康煙草和CMVΔ2b侵染煙草上煙蚜的凈生殖率(R)顯著高于CMV侵染煙草,健康煙草上煙蚜的總繁殖率GRR顯著高于CMVΔ2b侵染煙草。
圖中數(shù)據(jù)為平均數(shù)±標(biāo)準(zhǔn)誤。柱上不同小寫字母表示經(jīng)Bootstrap程序檢驗(yàn)差異顯著(P<0.05)
表3 不同煙草寄主上煙蚜的發(fā)育歷期及壽命
表中數(shù)據(jù)為平均值±標(biāo)準(zhǔn)誤。同一列內(nèi)不同小寫字母表示該參數(shù)經(jīng)Bootstrap程序檢驗(yàn)差異顯著(<0.05)。表4、表5同
Data in the table are mean±SE. Different lowercase letters in the same column indicate the parameter has a significant difference at 0.05 level (Bootstrap program). The same as Table 4 and Table 5
表4 不同煙草寄主上煙蚜的繁殖歷期及繁殖力
表5 不同煙草寄主上煙蚜的種群參數(shù)
植物病毒的傳播與介體昆蟲的取食與定殖密切相關(guān),在取食之前,介體昆蟲主要依靠視覺和嗅覺選擇目標(biāo)植物[25-26]。相較于健康植物,病毒侵染后的寄主植物釋放的揮發(fā)物發(fā)生改變且對(duì)介體昆蟲的選擇行為產(chǎn)生影響[3,8,27-28]。本研究發(fā)現(xiàn),煙蚜對(duì)健康煙草和CMVΔ2b侵染煙草有著更強(qiáng)的選擇趨向。而MAUCK等[8]研究發(fā)現(xiàn),CMV侵染西葫蘆后,與健康植株相比,帶毒植株釋放了更多的揮發(fā)性物質(zhì),吸引了桃蚜()和瓜蚜前來定殖取食,且蚜蟲在獲毒后會(huì)向健康植株遷移。Wu等[29]發(fā)現(xiàn)CMV 2b蛋白與擬南芥JAZ蛋白(茉莉酸信號(hào)的關(guān)鍵抑制因子)通過物理作用結(jié)合以阻止JAZ降解,從而減弱茉莉酸信號(hào)以增強(qiáng)寄主對(duì)介體蚜蟲的吸引力。但也有研究表明,CMV的侵染雖然改變了寄主植物的揮發(fā)物釋放,但并不能增加寄主植物對(duì)蚜蟲的吸引力[3]。以上研究結(jié)果之間的差異可能與寄主植物種類或病毒侵染階段不同有關(guān)。
植物病毒可以通過改變寄主植物營養(yǎng)成分的變化影響介體昆蟲的生長發(fā)育和取食行為,從而影響介體對(duì)病毒的傳播[7,12,30-31]。研究表明,蚜蟲在攝取并分解食物中的氨基酸后在體內(nèi)重新合成游離氨基酸,蚜蟲可以通過自我調(diào)控適應(yīng)氨基酸匱乏的取食狀況[32]。PVY的侵染導(dǎo)致煙草體內(nèi)可溶性糖和氨基酸含量的增加,促使有翅蚜的產(chǎn)生和擴(kuò)散,利于PVY的傳播[33]。從煙蚜在不同寄主上的取食行為來看,煙蚜在CMV侵染煙草上的刺探行為發(fā)生次數(shù)最多,并且花費(fèi)較少的時(shí)間在韌皮部進(jìn)食階段(E2波),這表明相較于CMVΔ2b侵染煙草和健康煙草,CMV侵染后煙草葉片的營養(yǎng)品質(zhì)和物理結(jié)構(gòu)并不適宜煙蚜取食。與健康煙草和CMVΔ2b侵染煙草相比,CMV侵染葉片中總糖含量降低,游離氨基酸的含量顯著升高,表明煙蚜偏好取食總糖含量高但氨基酸含量低的葉片組織,這與MAUCK等的研究結(jié)果相吻合[27]。非持久性病毒的傳播與蚜蟲在取食過程中的刺探行為密切相關(guān)[34-35],病毒的獲取和接種都發(fā)生在pd波階段,刺探行為的增加會(huì)提高非持久性病毒的傳播效率。相較于CMVΔ2b侵染煙草,CMV侵染煙草上煙蚜的刺探行為(pd波)發(fā)生頻率較高,GUO等[2]研究表明,蚜蟲在CMV侵染煙草上比在CMVΔ2b煙草上更易獲毒。因此推測(cè)在寄主植物、介體蚜蟲與病毒的互作關(guān)系中,CMV 2b基因可通過提高煙蚜的刺探頻率來促進(jìn)病毒的傳播。此外,G波的發(fā)生代表著蚜蟲在木質(zhì)部的主動(dòng)吸食,CMV侵染煙草上的煙蚜在木質(zhì)部吸食(G波)的發(fā)生概率高于健康煙草和CMVΔ2b侵染的煙草,這表明CMV侵染煙草上的煙蚜更容易發(fā)生木質(zhì)部進(jìn)食以獲取無機(jī)鹽和水分。
在植物病毒、介體昆蟲和寄主植物的互作關(guān)系中,寄主植物體內(nèi)的病毒含量影響寄主植物自身的防御水平以及介體昆蟲的繁殖力[36]。王佳等[37]研究發(fā)現(xiàn),CMV侵染的煙草抑制了煙蚜的種群增長率,降低煙草對(duì)煙蚜的適合度,促使蚜蟲選擇新寄主。本研究發(fā)現(xiàn),相較于健康煙草,CMV的侵染導(dǎo)致煙蚜若蚜歷期延長、壽命縮短、繁殖力降低,并造成煙蚜在2齡若蚜?xí)r的大量死亡,提高了整個(gè)若蚜期的死亡率;通過對(duì)煙蚜種群參數(shù)進(jìn)行分析,發(fā)現(xiàn)健康煙草有利于煙蚜生長發(fā)育和繁殖,CMV侵染煙草不適于煙蚜生長發(fā)育和繁殖,這與CMV侵染煙草導(dǎo)致氨基酸和總糖含量及其比例發(fā)生變化有關(guān),同時(shí)在試驗(yàn)中發(fā)現(xiàn)感染CMV的煙草葉片革質(zhì)化,這也不適于煙蚜取食。相較于CMV侵染煙株,煙蚜在CMVΔ2b侵染煙株和健康煙株上有著更好的適應(yīng)性。有研究表明CMV 2b基因參與寄主與介體蚜蟲互作,間接影響蚜蟲對(duì)CMV的傳播,病毒的其他蛋白也會(huì)與CMV 2b蛋白相互作用,共同調(diào)控寄主植物對(duì)蚜蟲的抗性[38-39],這也為在生產(chǎn)實(shí)踐中通過調(diào)控CMV 2b基因來控制蚜蟲傳播CMV提供了理論依據(jù),為減少CMV在田間的流行提供了防控新思路。
對(duì)于持久性傳播的病毒,如PLRV,病毒的侵染提高了寄主植物“營養(yǎng)品質(zhì)”,蚜蟲優(yōu)先定殖和取食受侵染的植物,種群快速增長,最終蚜蟲從受侵染寄主植株上向新寄主轉(zhuǎn)移,有利于病毒傳播[40]。對(duì)于非持久性傳播的CMV,本研究發(fā)現(xiàn)該病毒的侵染降低了寄主煙株的“營養(yǎng)品質(zhì)”,不適于煙蚜取食,從而降低煙蚜繁殖力并造成煙蚜大量死亡。MAUCK等[8,41]的研究表明,CMV侵染西葫蘆導(dǎo)致葉片“營養(yǎng)品質(zhì)”下降,蚜蟲種群數(shù)量顯著降低,且在受侵染西葫蘆上的煙蚜更容易被寄生蜂寄生。而同樣通過蚜蟲非持久性傳播的PVY在侵染煙草后,雖然提高了感病煙草上煙蚜的繁殖力,但有翅蚜產(chǎn)生高峰期提前,也同樣促進(jìn)了煙蚜的擴(kuò)散和傳毒[33]。由此可見,兩種傳播機(jī)制的病毒雖然介體的傳毒方式不同,但侵染寄主植物后,可通過調(diào)控寄主植物代謝或介體昆蟲的生長發(fā)育、取食行為、選擇行為等策略,進(jìn)一步影響病毒的傳播與流行。
CMV侵染煙草后,降低了介體煙蚜的寄主偏好性。CMV 2b基因的存在提高了煙蚜在煙草上的刺探頻率,不利于煙蚜在韌皮部的取食。CMV的侵染改變了煙草中總糖和游離氨基酸等營養(yǎng)物質(zhì)的組成,降低了煙蚜的寄主適合度。CMV的侵染對(duì)煙蚜的生長發(fā)育產(chǎn)生不利影響,延長了煙蚜的若蚜歷期、提高了若蚜的死亡率,降低了煙蚜壽命和繁殖力,促使蚜蟲尋找新的合適寄主,從而促進(jìn)了病毒的傳播。
[1] 朱賢朝, 王彥亭, 王智發(fā). 中國煙草病害. 北京: 中國農(nóng)業(yè)出版社, 2002: 76-89.
ZHU X C, WANG Y T, WANG Z F. Tobacco Disease of China. Beijing: China Agriculture Press, 2002: 76-89. (in Chinese)
[2] GUO H, GU L, LIU F, CHEN F, GE F, SUN Y. Aphid-borne viral spread is enhanced by virus-induced accumulation of plant reactive oxygen species. Plant Physiology, 2019, 179(1): 143-155.
[3] TUNGADI T, GROEN S C, MURPHY A M, PATE A E, IQBAL J, BRUCE T J A, CUNNIFFE N J, CARR J P. Cucumber mosaic virus and its 2b protein alter emission of host volatile organic compounds but not aphid vector settling in tobacco. Virology Journal, 2017, 14(1): 91.
[4] MAUCK K E, DE MORAES C M, MESCHER M C. Evidence of local adaptation in plant virus effects on host-vector interactions. Integrative and Comparative Biology, 2014, 54(2): 193-209.
[5] HILY J M, GARCIA A, MORENO A, PLAZA M, Wilkinson M D, FERERES A, FRAILE A, GARCIA-ARENAL F. The relationship between host lifespan and pathogen reservoir potential: an analysis in the system-cucumber mosaic virus.PLoS Pathogens, 2014, 10(11): e1004492.
[6] STAFFORD C A, WALKER G P, ULLMAN D E. Infection with a plant virus modifies vector feeding behavior. Proceedings of the National Academy of Science of the United States of America, 2011, 108(23): 9350-9355.
[7] MAUCK K E, DE MORAES C M, MESCHER M C. Deceptive chemical signals induced by a plant virus attract insect vectors to inferior hosts. Proceedings of the National Academy of Science of the United States of America, 2010, 107(8): 3600-3605.
[8] MAUCK K E, DE MORAES C M, MESCHER M C. Effects of cucumber mosaic virus infection on vector and non-vector herbivores of squash. Communicative and Integrative Biology, 2010, 3(6): 579-582.
[9] GADHAVE K R, DUTTA B, COOLONG T, SRINIVASAN R. A non-persistent aphid-transmitteddifferentially alters the vector and non-vector biology through host plant quality manipulation. Scientific reports, 2019, 9: 2503.
[10] CASTEEL C L, YANG C, NANDURI A C, DE JONG H N, WHITHAM S A, JANDER G. The NIa-Pro protein of turnip mosaic virus improves growth and reproduction of the aphid vector,(green peach aphid). The Plant Journal, 2014, 77(4): 653-663.
[11] KERSCH-BECKER M F, THALER J S. Virus strains differentially induce plant susceptibility to aphid vectors and chewing herbivores. Oecologia, 2014, 174(3): 883-892.
[12] LI H, LIU X, LIU X, MICHAUD J P, ZHI H, LI K, LI X, LI Z. Host plant infection by soybean mosaic virus reduces the fitness of its vector,(Hemiptera: Aphididae). Journal of Economic Entomology, 2018, 111(5): 2017-2023.
[13] NG J C, PERRY K L. Transmission of plant viruses by aphid vectors. Molecular Plant Pathology, 2004, 5(5): 505-511.
[14] STAFFORD C A, WALKER G P, ULLMAN D E. Hitching a ride: Vector feeding and virus transmission. Communicative and Integrative Biology, 2012, 5(1): 43-49.
[15] JIMéNEZ J, GARZO E, ALBA-TERCEDOR J, MORENO A, FERERES A, WALKER G P. The phloem-pd: a distinctive brief sieve element stylet puncture prior to sieve element phase of aphid feeding behavior. Arthropod-Plant Interactions, 2020, 14: 67-78.
[16] ALVAREZ A E, GARZO E, VERBEEK M, VOSMAN B, DICKE M, TJALLINGII W F. Infection of potato plants with potato leafroll virus changes attraction and feeding behaviour of. Entomologia Experimentalis et Applicata, 2007, 125(2): 135-144.
[17] COLLAR J L, AVILLA C, FERERES A. New correlations between aphid stylet paths and nonpersistent virus transmission. Environmental Entomology, 1997, 26(3): 537-544.
[18] REN G W, WANG X F, CHEN D, WANG X W, FAN X J, LIU X D. Potato virus Y-infected tobacco affects the growth, reproduction, and feeding behavior of a vector aphid,(Hemiptera: aphididae). Applied Entomology and Zoology, 2015, 50(2): 239-243.
[19] LIU J Y, LIU Y J, DONKERSLEY P, DONG Y H, CHEN X, ZANG Y, XU P J, REN G W. Preference of the aphid(Hemiptera: Aphididae) for tobacco plants at specific stages of potato virus Y infection. Archives of Virology, 2019, 164(6): 1567-1573.
[20] 姚敏, 張?zhí)炱? 田志超, 王源超, 陶小榮. 農(nóng)桿菌介導(dǎo)的CMV侵染性克隆及2b缺失突變體構(gòu)建. 中國農(nóng)業(yè)科學(xué), 2011, 44(14): 3060-3068.
YAO M, ZHANG T Q, TIAN Z C, WANG Y C, TAO X R. Construction of-mediated cucumber mosaic virus infectious cDNA clones and 2b deletion viral vector. Scientia Agricultura Sinica, 2011, 44(14): 3060-3068. (in Chinese)
[21] SARRIA E, CID M, GARZO E, FERERES A. Excel Workbook for automatic parameter calculation of EPG data. Computers and Electronics in Agriculture, 2009, 67(1/2): 35-42.
[22] 臧連生, 劉銀泉, 劉樹生. 一種適合粉虱實(shí)驗(yàn)觀察的新型微蟲籠. 昆蟲知識(shí), 2005, 42(3): 329-331.
Zang L S, Liu Y Q, Liu S S. A new clip-cage for whitefly experimental studies. Chinese Bulletin of Entomology, 2005, 42(3): 329-331. (in Chinese)
[23] CHI H. Life-table analysis incorporating both sexes and variable development rates among individuals. Environmental Entomology, 1988, 17(1): 26-34.
[24] CHI H, LIU H. Two new methods for the study of insect population ecology. Bulletin of the Institute of Zoology Academia Sinica, 1985, 24(2): 225-240.
[25] KARIYAT R R, MAUCK K E, BALOGH C M, STEPHENSON A G, MESCHER M C, DE MORAES C M. Inbreeding in horsenettle () alters night-time volatile emissions that guide oviposition bymoths. Proceedings of the Royal Society B: Biological Sciences, 2013, 280(1757): 20130020.
[26] MAXWELL D J, PARTRIDGE J C, ROBERTS N W, BOONHAM N, FOSTER G D. The effects of plant virus infection on polarization reflection from leaves. PLoS One, 2016, 11(4): e0152836.
[27] MAUCK K E, DE MORAES C M, MESCHER M C. Biochemical and physiological mechanisms underlying effects of cucumber mosaic virus on host-plant traits that mediate transmission by aphid vectors. Plant, Cell and Environment, 2014, 37(6): 1427-1439.
[28] DYER L A, PHILBIN C S, OCHSENRIDER K M, RICHARDS L A, MASSAD T J, SMILANICH A M, FORISTER M L, PARCHMAN T L, GALLAND L M, HURTADO P J,. Modern approaches to study plant-insect interactions in chemical ecology. Nature Reviews Chemistry, 2018, 2(6): 50-64.
[29] WU D, QI T, LI W X, TIAN H, GAO H, WANG J, GE J, YAO R, REN C, WANG X B, LIU Y, KANG L, DING S W, XIE D. Viral effector protein manipulates host hormone signaling to attract insect vectors. Cell Research, 2017, 27(3): 402-415.
[30] EIGENBRODE S D, DING H, SHIEL P, BERGER P H. Volatiles from potato plants infected with potato leafroll virus attract and arrest the virus vector,(Homoptera: Aphididae). Proceedings of the Royal Society of London B: Biological Sciences, 2002, 269(1490): 455-460.
[31] MAUCK K, BOSQUE-PéREZ N A, EIGENBRODE S D, DE MORAES C M, MESCHER M C. Transmission mechanisms shape pathogen effects on host-vector interactions: evidence from plant viruses. Functional Ecology, 2012, 26(5): 1162-1175.
[32] Wu J, Lan H, Zhang Z F, Cao H H, Liu T X. Performance and transcriptional response of the green peach aphidto the restriction of dietary amino acids. Frontiers in Physiology, 2020, 11: 487.
[33] 陳茜, 劉金燕, 徐蓬軍, 劉英杰, 董勇浩, 臧云, 蔡憲杰, 任廣偉. PVY侵染后煙草營養(yǎng)成分的變化及其對(duì)介體煙蚜生長發(fā)育的影響. 昆蟲學(xué)報(bào), 2020, 63(2): 181-190.
CHEN X, LIU J Y, XU P J, LIU Y J, DONG Y H, ZANG Y, CAI X J, REN G W. Changes in the nutrient composition of tobacco plants after potato virus Y infection and their effects on the growth and development of the vector(Hemiptera: Aphididae).Acta Entomologica Sinica, 2020, 63(2): 181-190. (in Chinese)
[34] MARTIN B, COLLAR J L, TJALLINGII W F, FERERES A. Intracellular ingestion and salivation by aphids may cause the acquisition and inoculation of non-persistently transmitted plant viruses. Journal of General Virology, 1997, 78: 2701-2705.
[35] POWELL G. Intracellular salivation is the aphid activity associated with inoculation of non-persistently transmitted viruses. Journal of General Virology, 2005, 86(2): 469-472.
[36] SHI X, GAO Y, YAN S, TANG X, ZHOU X, ZHANG D, LIU Y. Aphid performance changes with plant defense mediated by cucumber mosaic virus titer. Virology Journal, 2016, 13: 70.
[37] 王佳, 王亞峰, 蒲頗, 陳媛, 劉映紅. 煙草感染兩種病毒對(duì)煙蚜種群增長、寄主選擇與傳毒的影響. 西南大學(xué)學(xué)報(bào) (自然科學(xué)版), 2017, 39(3): 23-27.
WANG J, WANG Y F, PU P, CHEN Y, LIU Y H. Effect of two viruses infecting tobacco on population growth, host plant selection and virus transmission efficiency of aphids. Journal of Southwest University (Natural Science Edition), 2017, 39(3): 23-27. (in Chinese)
[38] ZIEBELL H, MURPHY A M, GROEN S C, TUNGADI T, WESTWOOD J H, LEWSEY M G, MOULIN M, KLECZKOWSKI A, SMITH A G, STEVENS M, POWELL G, CARR J P. Cucumber mosaic virus and its 2b RNA silencing suppressor modify plant-aphid interactions in tobacco. Scientific Reports, 2011, 1: 187.
[39] TUNGADI T, DONNELLY R, QING L, IQBAL J, MURPHY A M, PATE A E, CUNNIFFE N J, CARR J P. Cucumber mosaic virus 2b proteins inhibit virus-induced aphid resistance in tobacco. Molecular Plant Pathology, 2020, 21(2): 250-257.
[40] CASTLE S J, BERGER P H. Rates of growth and increase ofon virus-infected potatoes according to type of virus-vector relationship. Entomologia Experimentalis et Applicata, 1993, 69(1): 51-60.
[41] MAUCK K E, DE MORAES C M, MESCHER M C. Infection of host plants by cucumber mosaic virus increases the susceptibility ofaphids to the parasitoid. Scientific Reports, 2015, 5: 10963.
Effects of CMV-infected Tobacco on the Performance, Feeding and Host Selection Behavior of
CHEN Xi1, LIU YingJie1,2, DONG YongHao1, LIU JinYan1, LI Wei1, XU PengJun1, ZANG Yun1, REN GuangWei1
1Tobacco Research Institute, Chinese Academy of Agricultural Sciences, Qingdao 266101, Shandong;2Staff Development Institute of China National Tobacco Corporation, Zhengzhou 450008
【】The objective of this study is to investigate the effect ofcucumber mosaic virus(CMV) infection on the growth, development and behavior ofon tobacco, and the role of 2b gene in the interaction betweenand CMV.【】The host plants to be used were healthy tobacco, CMV-infected and CMV 2b gene deletion mutant (CMVΔ2b) infected tobacco. The Y-shaped olfactometer was used to determinate the selection tendency ofto different host tobacco plants, and electrical penetration graph (EPG) was used to monitorfeeding behavior combined with the detection of total sugar and free amino acid content in the host plant. The aphid life table was recorded through a single micro-cage to analyze the effects of CMV-infected tobacco on the growth and reproduction of.【】The total sugar content of CMV-infected tobacco was significantly lower than that of healthy tobacco, while the content of free amino acids was significantly higher than that of healthy tobacco and CMVΔ2b-infected tobacco. The contents of threonine, glutamic acid, glycine, tyrosine, histidine, arginine and proline in the tobacco infected by CMVΔ2b were significantly higher than those of other treatments. The contents of valine and lysine in CMVΔ2b-infected tobacco were significantly higher than those of healthy tobacco. The content of aspartic acid in CMV-infected tobacco was significantly lower than that of other treatments, and its cystine content was significantly higher than that of CMVΔ2b-infected tobacco. Compared with CMV-infected tobacco,had a stronger selection trend to healthy tobacco and CMVΔ2b-infected tobacco. There was no significant difference in the host selection behavior ofbetween healthy tobacco and CMVΔ2b-infected tobacco. CMV infection adversely affected the growth and feeding behavior of.had the most frequent probing behavior (pd wave) and the shortest duration of phloem feeding (E2 wave) on CMV-infected tobacco, and the frequency of xylem feeding (G wave) was significantly higher than that of healthy tobacco and CMVΔ2b-infected tobacco. The results indicated that CMV-infected tobacco was not suitable for aphid feeding. The growth characteristics of theshowed that CMV infection significantly prolonged the duration of the nymph aphid, increased the mortality rate of the 2nd-instar aphid, reduced the longevity of the aphid, and significantly reduced the fecundity of the aphid. The intrinsic rate of increase () and finite rate of increase () ofon CMV-infected tobacco were significantly lower than those of healthy and CMVΔ2b-infected tobacco. CMV infection was not conducive to population growth of.【】CMV infection changes the composition of tobacco nutrients. The presence of CMV 2b gene increases the probing frequency and reduces the phloem feeding behavior. CMV infection results in prolonging pre-adult period, increasing mortality, decreasing longevity and fecundity of. CMV infection reduces the host fitness of, promotes aphids to transfer to new host plants, thus promoting the spread of the CMV.
cucumber mosaic virus(CMV);; tobacco; growth and development; feeding behavior; host selection
10.3864/j.issn.0578-1752.2021.08.008
2020-07-01;
2020-08-14
中央級(jí)公益性科研院所基本科研業(yè)務(wù)費(fèi)專項(xiàng)(1610232020009)、中國農(nóng)業(yè)科學(xué)院創(chuàng)新工程(ASTIP-TRIC04)、中國煙草總公司重點(diǎn)實(shí)驗(yàn)室項(xiàng)目(110201603011)
陳茜,E-mail:chenxi960419@163.com。通信作者任廣偉,E-mail:renguangwei@caas.cn
(責(zé)任編輯 岳梅)