近年来,受秸秆粗放还田、气候变化等因素影响,由禾谷镰孢复合种(Fusarium graminearum species complex)引起的小麦赤霉病在我国频繁暴发流行,成为长江中下游和黄淮海等小麦主产区的主要病害,严重影响小麦稳产丰收。病菌产生的脱氧雪腐...近年来,受秸秆粗放还田、气候变化等因素影响,由禾谷镰孢复合种(Fusarium graminearum species complex)引起的小麦赤霉病在我国频繁暴发流行,成为长江中下游和黄淮海等小麦主产区的主要病害,严重影响小麦稳产丰收。病菌产生的脱氧雪腐镰刀菌烯醇和玉米赤霉烯酮等真菌毒素也严重威胁小麦质量安全。当前,由于缺乏高抗小麦品种,化学防治仍然是赤霉病防控的重要措施,但随着单一作用方式药剂的长期使用,病菌抗药性问题也逐渐加重。本文综述了禾谷镰孢复合种对苯并咪唑类杀菌剂、甾醇脱甲基抑制剂、肌球蛋白抑制剂、琥珀酸脱氢酶抑制剂等几类常用药剂的抗性现状和抗性机制。在此基础上,探讨禾谷镰孢复合种的抗药性治理对策。展开更多
Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threa...Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and livestock.Xinong 979(XN979)is a widely cultivated wheat elite with high yield and FHB resistance.However,its resistance mechanism remains unclear.In this study,we studied the expression of genes involved in plant defense in XN979 by comparative transcriptomics.We found that the FHB resistance in XN979 consists of two lines of defense.The first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis genes.The second line of defense,which is induced upon F.graminearum infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding genes.Meanwhile,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection stage.The formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance traits.This study will facilitate our understanding of wheat-F.graminearum interaction and is insightful for breeding FHB-resistant wheat.展开更多
Salicylic acid(SA),a vital endogenous hormone,plays a crucial role in plant growth and the response to abiotic and biotic stress.Isochorismate synthase(ICS)and phenylalanine ammonia lyase(PAL)are critical rate-limitin...Salicylic acid(SA),a vital endogenous hormone,plays a crucial role in plant growth and the response to abiotic and biotic stress.Isochorismate synthase(ICS)and phenylalanine ammonia lyase(PAL)are critical rate-limiting enzymes for SA synthesis.Fusarium head blight(FHB)seriously threatens the safety of wheat production,but increasing the content of SA can enhance FHB resistance.However,the pathway of SA synthesis and regulation in wheat remains unknown.In this study,three wheat ICS(TaICSA,TaICSB,and TaICSD)were identified,and their functions were validated in vitro for isomerizing chorismate to isochorismate.The mutation of one or two homoeoalleles of TaICSA,TaICSB,and TaICSD in the wheat variety‘Cadenza’reduced SA levels under ultraviolet treatment and Fusarium graminearum infection,further enhancing sensitivity to FHB.Overexpression of TaICSA can significantly enhance SA levels and resistance to FHB.To further study SA synthesis pathways in wheat and avoid interference with pathogenicity related genes,the leaves of wild-type Cadenza and different TaICS mutant lines were subjected to ultraviolet treatment for transcriptomic analysis.The results showed that 37 PALs might be involved in endogenous SA synthesis,and 82 WRKY and MYB family transcription factors may regulate the expression of ICS and PAL.These results were further confirmed by RT-PCR.In conclusion,this study expands our knowledge of SA biosynthesis and identifies TaICSA,as well as several additional candidate genes that encode transcription factors for regulating endogenous SA levels,as part of an efficient strategy for enhancing FHB resistance in wheat.展开更多
文摘近年来,受秸秆粗放还田、气候变化等因素影响,由禾谷镰孢复合种(Fusarium graminearum species complex)引起的小麦赤霉病在我国频繁暴发流行,成为长江中下游和黄淮海等小麦主产区的主要病害,严重影响小麦稳产丰收。病菌产生的脱氧雪腐镰刀菌烯醇和玉米赤霉烯酮等真菌毒素也严重威胁小麦质量安全。当前,由于缺乏高抗小麦品种,化学防治仍然是赤霉病防控的重要措施,但随着单一作用方式药剂的长期使用,病菌抗药性问题也逐渐加重。本文综述了禾谷镰孢复合种对苯并咪唑类杀菌剂、甾醇脱甲基抑制剂、肌球蛋白抑制剂、琥珀酸脱氢酶抑制剂等几类常用药剂的抗性现状和抗性机制。在此基础上,探讨禾谷镰孢复合种的抗药性治理对策。
基金This work was supported by the grants from the National Key R&D Program of China(2022YFD1400100)the National Natural Science Foundation of China(32072505 and 31701747)+1 种基金the Chinese Universities Scientific Fund(2452020222)the National Innovation and Entrepreneurship Training Program for College Students China(202110712255)。
文摘Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and livestock.Xinong 979(XN979)is a widely cultivated wheat elite with high yield and FHB resistance.However,its resistance mechanism remains unclear.In this study,we studied the expression of genes involved in plant defense in XN979 by comparative transcriptomics.We found that the FHB resistance in XN979 consists of two lines of defense.The first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis genes.The second line of defense,which is induced upon F.graminearum infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding genes.Meanwhile,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection stage.The formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance traits.This study will facilitate our understanding of wheat-F.graminearum interaction and is insightful for breeding FHB-resistant wheat.
基金supported by the National Natural Science Foundation of China(3210170116)the Science and Technology Department of Sichuan Province(2022YFSY0035).
文摘Salicylic acid(SA),a vital endogenous hormone,plays a crucial role in plant growth and the response to abiotic and biotic stress.Isochorismate synthase(ICS)and phenylalanine ammonia lyase(PAL)are critical rate-limiting enzymes for SA synthesis.Fusarium head blight(FHB)seriously threatens the safety of wheat production,but increasing the content of SA can enhance FHB resistance.However,the pathway of SA synthesis and regulation in wheat remains unknown.In this study,three wheat ICS(TaICSA,TaICSB,and TaICSD)were identified,and their functions were validated in vitro for isomerizing chorismate to isochorismate.The mutation of one or two homoeoalleles of TaICSA,TaICSB,and TaICSD in the wheat variety‘Cadenza’reduced SA levels under ultraviolet treatment and Fusarium graminearum infection,further enhancing sensitivity to FHB.Overexpression of TaICSA can significantly enhance SA levels and resistance to FHB.To further study SA synthesis pathways in wheat and avoid interference with pathogenicity related genes,the leaves of wild-type Cadenza and different TaICS mutant lines were subjected to ultraviolet treatment for transcriptomic analysis.The results showed that 37 PALs might be involved in endogenous SA synthesis,and 82 WRKY and MYB family transcription factors may regulate the expression of ICS and PAL.These results were further confirmed by RT-PCR.In conclusion,this study expands our knowledge of SA biosynthesis and identifies TaICSA,as well as several additional candidate genes that encode transcription factors for regulating endogenous SA levels,as part of an efficient strategy for enhancing FHB resistance in wheat.
