Cesarini Marco, Petrucci Arianna, Hotaj Eliverta, Venturini Giovanni, Liguori Riccardo, Sarrocco Sabrina
Department of Agriculture, Food and Environment, University of Pisa, Italy.
Department of Agriculture, Food and Environment, University of Pisa, Italy; Department of Plant and Environmental Sciences and Copenhagen Plant Science Centre, University of Copenhagen, Denmark.
Microbiol Res. 2025 Jan;290:127941. doi: 10.1016/j.micres.2024.127941. Epub 2024 Oct 24.
Fusarium head blight (FHB) represents a significant threat for wheat production due to the risk for food security and safety. Despite the huge number of biofungicides on the market, only one is actually available at European level to control Fusarium infections on cereals. The present work aimed to assess the possible use of Trichoderma asperellum strain ICC012 and Trichoderma gamsii strain ICC080 to manage FHB on common wheat Triticum aestivum cv Apogee. Initially, the capability of ICC012 and ICC080 to endophytically colonize wheat roots, a prerequisite very often correlated with the induction of resistance in the host plant, was investigated. It resulted in 100 % of roots internally colonized by the two strains, followed by a significant up-regulation of the defense-related genes encoding for pathogenesis-related protein 1 (pr1), superoxide dismutase (sod), polygalacturonase inhibitor protein 2 (pgip2) and phenylalanine ammonia-lyase 1 (pal1). When the expression of the same genes was investigated in spikes treated at the flowering stage with the two strains, applied individually or co-inoculated, a significant up-regulation of only pal1 was registered 24 hours post inoculation (hpi) in spikes treated with ICC080. To check if a systemic defense response was induced, the expression of the same genes was analyzed in leaves collected 7 and 14 days post inoculation (dpi) of roots, resulting in a significant up-regulation of sod at 7 dpi in leaves collected from plants inoculated with ICC012. Even if induction of resistance is probably not the main mode of action of the two strains, ICC012 and ICC080 applied on spikes at anthesis significantly reduced, in greenhouse conditions, the Disease Incidence (DI) caused by the inoculation mix of F. graminearum, F. culmorum, F. langsethiae and F. sporotrichioides, four of the most important FHB casual agents. This reduction in disease symptoms was observed when the two beneficial strains were applied both individually and co-inoculated on the spikes. Finally, ICC012 and ICC080 demonstrated a good competitive ability for substrate possession. The amount of F. graminearum (as DNA and number of perithecia) on wheat straw pieces was significantly reduced after 6 months of incubation in presence of the two beneficial strains, applied individually and co-inoculated. Being cultural debris used to overwinter, this competitive behavior of ICC012 and ICC080 is an important trait to reduce the potential inoculum of the pathogen. The results collected here lay the groundwork for the use of ICC012 and ICC080 in managing FHB on common wheat.
由于对粮食安全和食品安全构成风险，小麦赤霉病（FHB）对小麦生产构成重大威胁。尽管市场上有大量生物杀菌剂，但在欧洲层面实际上只有一种可用于控制谷物上的镰刀菌感染。本研究旨在评估棘孢木霉菌株ICC012和甘氏木霉菌株ICC080在普通小麦品种Apogee上防治小麦赤霉病的可能性。首先，研究了ICC012和ICC080内生定殖小麦根的能力，这一前提条件通常与宿主植物抗性的诱导相关。结果表明，两种菌株均能100%定殖于根内部，随后编码病程相关蛋白1（pr1）、超氧化物歧化酶（sod）、多聚半乳糖醛酸酶抑制蛋白2（pgip2）和苯丙氨酸解氨酶1（pal1）的防御相关基因显著上调。当在开花期用这两种菌株单独或共同接种处理穗部后，研究相同基因的表达时，在用ICC080处理的穗部接种后24小时（hpi）仅pal1显著上调。为了检查是否诱导了系统防御反应，在接种根后7天和14天（dpi）采集叶片分析相同基因的表达，结果在用ICC012接种的植物采集的叶片中，7 dpi时sod显著上调。即使抗性诱导可能不是这两种菌株的主要作用方式，但在温室条件下，花期在穗部施用ICC012和ICC080显著降低了由禾谷镰刀菌、燕麦镰刀菌、黄色镰刀菌和拟分枝孢镰刀菌（四种最重要的小麦赤霉病病原菌）接种混合物引起的发病率（DI）。当单独或共同在穗部施用这两种有益菌株时，均观察到病害症状减轻。最后，ICC012和ICC080表现出良好的底物占有竞争能力。在单独和共同施用这两种有益菌株的情况下，经过6个月的培养后，小麦秸秆碎片上的禾谷镰刀菌数量（以DNA和子囊壳数量计）显著减少。由于作物残体是病原菌越冬的场所，ICC012和ICC080的这种竞争行为是减少病原菌潜在接种量的一个重要特性。这里收集的结果为在普通小麦上使用ICC012和ICC080防治小麦赤霉病奠定了基础。
