Jasmonate and ethylene dependent defence gene expression and suppression of fungal virulence factors: two essential mechanisms of Fusarium head blight resistance in wheat?

BMC Genomics

Research Article

Birgit Samans¹  Stefanie Lück²  Sven Gottwald²  Wolfgang Friedt² 

[1] Biometry and Population Genetics, Justus-Liebig University, Institute of Agronomy and Plant Breeding II, Heinrich-Buff-Ring 26-32, D-35392, Giessen, Germany;Department of Plant Breeding, Justus-Liebig University, Institute of Agronomy and Plant Breeding I, Heinrich-Buff-Ring 26-32, D-35392, Giessen, Germany;

关键词: Graminearum;    Jasmonic Acid;    Fusarium Head Blight;    Fusarium Head Blight Resistance;    nsLTP Gene;   

DOI  :  10.1186/1471-2164-13-369

 received in 2012-02-03, accepted in 2012-06-21,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundFusarium head blight (FHB) caused by Fusarium species like F. graminearum is a devastating disease of wheat (Triticum aestivum) worldwide. Mycotoxins such as deoxynivalenol produced by the fungus affect plant and animal health, and cause significant reductions of grain yield and quality. Resistant varieties are the only effective way to control this disease, but the molecular events leading to FHB resistance are still poorly understood. Transcriptional profiling was conducted for the winter wheat cultivars Dream (moderately resistant) and Lynx (susceptible). The gene expressions at 32 and 72 h after inoculation with Fusarium were used to trace possible defence mechanisms and associated genes. A comparative qPCR was carried out for selected genes to analyse the respective expression patterns in the resistant cultivars Dream and Sumai 3 (Chinese spring wheat).ResultsAmong 2,169 differentially expressed genes, two putative main defence mechanisms were found in the FHB-resistant Dream cultivar. Both are defined base on their specific mode of resistance. A non-specific mechanism was based on several defence genes probably induced by jasmonate and ethylene signalling, including lipid-transfer protein, thionin, defensin and GDSL-like lipase genes. Additionally, defence-related genes encoding jasmonate-regulated proteins were up-regulated in response to FHB. Another mechanism based on the targeted suppression of essential Fusarium virulence factors comprising proteases and mycotoxins was found to be an essential, induced defence of general relevance in wheat. Moreover, similar inductions upon fungal infection were frequently observed among FHB-responsive genes of both mechanisms in the cultivars Dream and Sumai 3.ConclusionsEspecially ABC transporter, UDP-glucosyltransferase, protease and protease inhibitor genes associated with the defence mechanism against fungal virulence factors are apparently active in different resistant genetic backgrounds, according to reports on other wheat cultivars and barley. This was further supported in our qPCR experiments on seven genes originating from this mechanism which revealed similar activities in the resistant cultivars Dream and Sumai 3. Finally, the combination of early-stage and steady-state induction was associated with resistance, while transcript induction generally occurred later and temporarily in the susceptible cultivars. The respective mechanisms are attractive for advanced studies aiming at new resistance and toxin management strategies.

【 授权许可】

Unknown   
© Gottwald et al.; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.