Senatore M T, Ward T J, Cappelletti E, Beccari G, McCormick S P, Busman M, Laraba I, O'Donnell K, Prodi A
Department of Agricultural and Food Sciences, Alma Mater Studiorum University of Bologna, Viale G. Fanin, 44, 40127 Bologna, Italy.
US Department of Agriculture, Agricultural Research Service, National Center for Agricultural Utilization Research, Mycotoxin Prevention and Applied Microbiology Research Unit, 1815 North University Street, Peoria, IL 60604-3999, USA.
Int J Food Microbiol. 2021 Nov 16;358:109298. doi: 10.1016/j.ijfoodmicro.2021.109298. Epub 2021 Jun 15.
Fusarium head blight (FHB) is a global cereal disease caused by a complex of Fusarium species. In Europe, the main species responsible for FHB are F. graminearum, F. culmorum and F. poae. However, members of the F. tricinctum species complex (FTSC) have become increasingly important. FTSC fusaria can synthesize mycotoxins such as moniliformin (MON), enniatins (ENNs) and several other biologically active secondary metabolites that could compromise food quality. In this study, FTSC isolates primarily from Italian durum wheat and barley, together with individual strains from four non-graminaceous hosts, were collected to assess their genetic diversity and determine their potential to produce mycotoxins in vitro on rice cultures. A multilocus DNA sequence dataset (TEF1, RPB1 and RPB2) was constructed for 117 isolates from Italy and 6 from Iran to evaluate FTSC species diversity and their evolutionary relationships. Phylogenetic analyses revealed wide genetic diversity among Italian FTSC isolates. Among previously described FTSC species, F. avenaceum (FTSC 4) was the most common species in Italy (56/117 = 47.9%) while F. tricinctum (FTSC 3), and F. acuminatum (FTSC 2) accounted for 11.1% (13/117) and the 8.5% (10/117), respectively. The second most detected species was a new and unnamed Fusarium sp. (FTSC 12; 32/117 = 19%) resolved as the sister group of F. tricinctum. Collectively, these four phylospecies accounted for 111/117 = 94.9% of the Italian FTSC collection. However, we identified five other FTSC species at low frequencies, including F. iranicum (FTSC 6) and three newly discovered species (Fusarium spp. FTSC 13, 14, 15). Of the 59 FTSC isolates tested for mycotoxin production on rice cultures, 54 and 55 strains, respectively, were able to produce detectable levels of ENNs and MON. In addition, we confirmed that the ability to produce bioactive secondary metabolites such as chlamydosporol, acuminatopyrone, longiborneol, fungerin and butanolide is widespread across the FTSC.
镰刀菌穗腐病（FHB）是一种由多种镰刀菌引起的全球性谷物病害。在欧洲，导致FHB的主要菌种是禾谷镰刀菌、燕麦镰刀菌和梨孢镰刀菌。然而，三线镰刀菌种复合体（FTSC）的成员变得越来越重要。FTSC镰刀菌能够合成诸如串珠镰刀菌素（MON）、恩镰孢菌素（ENNs）等霉菌毒素以及其他几种可能影响食品质量的生物活性次生代谢产物。在本研究中，收集了主要来自意大利硬粒小麦和大麦的FTSC分离株，以及来自四种非禾本科寄主的单个菌株，以评估它们的遗传多样性，并确定它们在水稻培养物上体外产生霉菌毒素的潜力。构建了一个多位点DNA序列数据集（TEF1、RPB1和RPB2），用于分析来自意大利的117个分离株和来自伊朗的6个分离株，以评估FTSC物种多样性及其进化关系。系统发育分析揭示了意大利FTSC分离株之间广泛的遗传多样性。在先前描述的FTSC物种中，燕麦镰刀菌（FTSC 4）是意大利最常见的物种（56/117 = 47.9%），而三线镰刀菌（FTSC 3）和锐顶镰刀菌（FTSC 2）分别占11.1%（13/117）和8.5%（10/117）。第二常见的物种是一种新的未命名镰刀菌属物种（FTSC 12；32/117 = 19%），被确定为三线镰刀菌的姐妹群。总体而言，这四个系统发育种占意大利FTSC收集菌株的111/117 = 94.9%。然而，我们还鉴定出了其他五个低频FTSC物种，包括伊朗镰刀菌（FTSC 6）和三个新发现的物种（镰刀菌属物种FTSC 13、14、15）。在59个用于水稻培养物上霉菌毒素产生测试的FTSC分离株中，分别有54株和55株能够产生可检测水平的ENNs和MON。此外，我们证实了产生诸如厚垣孢子醇、锐顶孢吡喃酮、长叶烯醇、真菌素和丁醇内酯等生物活性次生代谢产物的能力在FTSC中广泛存在。
