劉春元 邢小萍 韓衛麗



摘要 為建立玉米雜交種和自交系利用擬輪枝鐮孢菌毒素抗性篩選的試驗方法,制備擬輪枝鐮孢菌毒素粗提液,測定不同稀釋倍數毒素粗提液對2個玉米雜交種和4個玉米自交系處理4 和6 d后的種子發芽抑制率、胚根生長抑制率以及幼苗致萎效果,分析不同抗性玉米種質、毒素稀釋倍數和處理時間對玉米種子發芽、胚根和幼苗生長的影響。結果表明,易感雜交種豫玉22與抗性雜交種農大108的種子發芽抑制率和胚根生長抑制率均存在極顯著差異(P<0.01);在處理后4、6 d時,前者的種子發芽抑制率、胚根生長抑制率分別比后者高7.2%、11.3%、12.7%、11.8%。在對玉米雜交種幼苗致萎蔫試驗中,用稀釋2倍和5倍的毒素粗提液處理,豫玉22與農大108雜交種幼苗間的萎蔫程度也存在顯著差異(P<0.05)。擬輪枝鐮孢菌毒素粗提液對不同抗性玉米種質種子發芽、幼苗生長的影響存在顯著差異,為利用擬輪枝鐮孢菌毒素粗提液對玉米品種進行苗枯病抗性鑒定和篩選提供理論依據。
關鍵詞 玉米苗枯病;擬輪枝鐮孢菌;毒素粗提液;發芽率;胚根生長
中圖分類號 S432.1文獻標識碼 A
文章編號 0517-6611(2019)19-0158-04
doi:10.3969/j.issn.0517-6611.2019.19.046
Abstract In order to establish a simple method for evaluating the resistance of maize hybrids and inbred lines,? the crude toxin extract from the culture medium of Fusarium verticillioides was prepared , and? the seed germination inhibition rate, radicle growth inhibition rate, as well as the wilting degree of 2 maize hybrids and 4 inbred lines under the treatment of the crude toxin at various dilutions and different treatment duration (4 or 6 d) were determined. The results showed that the susceptible hybrid Yuyu22 and resistant hybrid Nongda108 significantly differed in the inhibition rates of seed germination and radicle growth (P<0.01), and the inhibition rates of seed germination and radicle growth of Yuyu22 were 7.2%, 11.3% and 12.7%, 11.8% higher than those of Nongda 108. An obvious difference between Yuyu22 and Nongda108 was also found under the treatment of the crude toxin extract at 2 and 5 diluted solution (P<0.05).
The effects of crude extracts of fusarium rotatum toxin on seed germination and seedling growth of different resistant maize germplasms were obviously different, which provided certain basis for identification and screening of resistance to bacterial blight of maize varieties by using crude extracts of fusarium rotatum toxin.
Key words Maize seedling wilt disease;Fusarium verticillioides;Crude toxin extract;Germination rate;Radicle growth
玉米苗枯病是玉米生產中發生廣泛、為害嚴重的病害之一。近年來,由于感病品種推廣、種子帶菌、栽培管理粗放及環境條件改變等原因,導致該病頻繁發生,對玉米生產造成嚴重影響[1-3]。引起玉米苗枯病的病菌主要有鐮孢菌、立枯絲核菌、腐霉菌等。其中,擬輪枝鐮孢菌(Fusarium verticillioides)是主要病原菌之一[4-7]。該病菌寄主范圍廣泛,能侵染玉米、小麥等多種糧食作物,常引起苗枯、莖腐、穗腐等癥狀,對作物生產造成嚴重損失。該菌有性態為藤倉赤霉(Gibberella fujikuroi),在為害寄主的過程中,能產生多種非寄主?;舅?,對人和動物有很強的毒性[8]。研究表明,除影響糧食及其產品安全外,該類毒素還與人類癌癥發生有關[9-10]。
利用抗病品種是防治該病的有效措施之一[7]。近年來,利用病原菌毒素進行抗性材料的篩選逐漸成為品種抗性鑒定的一項重要方法。……