Inbaia Safieddin, Farooqi Arifa, Ray Rumiana V
Division of Plant and Crop Sciences, School of Biosciences, University of Nottingham, Loughborough, United Kingdom.
Front Plant Sci. 2023 Mar 8;14:1121553. doi: 10.3389/fpls.2023.1121553. eCollection 2023.
avenaceum causing Fusarium seedling blight (FSB) and Fusarium head blight (FHB) on barley is associated with economic losses of crop yield and quality, and the accumulation of mycotoxins including the enniatins (ENNs) A, A1, B and B1. Although is the main producer of ENNs, studies on the ability of isolates to cause severe Fusarium diseases or produce mycotoxins in barley are limited.
In this work, we investigated the aggressiveness of nine isolates of to two cultivars of malting barley, Moonshine and Quench, and defined their ENN mycotoxin profiles in and in planta experiments. We assessed and compared the severity of FSB and FHB caused by these isolates to disease severity by F. graminearum, . Quantitative real-time polymerase chain reaction and Liquid Chromatography Tandem Mass Spectrometry assays were used to quantify pathogen DNA and mycotoxin accumulation, respectively, in barley heads.
Isolates of were equally aggressive to barley stems and heads and caused the most severe FSB symptoms resulting in up to 55% reductions of stem and root length. Fusarium graminearum caused the most severe FHB disease, followed by the isolates of with the most aggressive isolates capable of causing similar bleaching of barley heads as . Fusarium avenaceum isolates produced ENN B as the predominant mycotoxin, followed by ENN B1 and A1 . However, only the most aggressive isolates produced ENN A1 in planta and none produced ENN A or beauvericin (BEA) either in planta or .
The capacity of isolates to produce ENNs was related to the accumulation of pathogen DNA in barley heads, whilst FHB severity was related to the synthesis and accumulation of ENN A1 in planta. Cv. Moonshine was significantly more resistant than Quench to FSB or FHB, caused by any Fusarium isolate, and to the accumulation of pathogen DNA, ENNs or BEA. In conclusion, aggressive F. avenaceum isolates are potent ENN producers causing severe FSB and FHB with ENN A1 requiring further investigation as potential virulence factor for in cereals.
燕麦镰孢菌可引发大麦的镰刀菌幼苗枯萎病（FSB）和赤霉病（FHB），这会导致作物产量和品质的经济损失，以及包括恩镰孢菌素（ENNs）A、A1、B和B1在内的霉菌毒素的积累。尽管燕麦镰孢菌是ENNs的主要产生菌，但关于其菌株在大麦中引发严重镰刀菌病害或产生霉菌毒素能力的研究有限。
在本研究中，我们调查了9株燕麦镰孢菌对两个麦芽大麦品种“月光”和“淬火”的侵染力，并在体外和植物体内实验中确定了它们的ENN霉菌毒素谱。我们评估并比较了这些菌株引起的FSB和FHB的严重程度与禾谷镰孢菌引起的病害严重程度。分别使用定量实时聚合酶链反应和液相色谱串联质谱分析法来量化大麦穗中病原体DNA和霉菌毒素的积累。
燕麦镰孢菌菌株对大麦茎和穗的侵染力相当，导致了最严重的FSB症状，使茎和根长度最多减少55%。禾谷镰孢菌引起了最严重的FHB病害，其次是燕麦镰孢菌菌株，其中侵染力最强的菌株能够导致与禾谷镰孢菌相似的大麦穗漂白。燕麦镰孢菌菌株产生的主要霉菌毒素是ENN B，其次是ENN B1和A1。然而，只有侵染力最强的菌株在植物体内产生ENN A1，且在植物体内或体外均无菌株产生ENN A或白僵菌素（BEA）。
燕麦镰孢菌菌株产生ENNs的能力与大麦穗中病原体DNA的积累有关，而FHB的严重程度与植物体内ENN A1的合成和积累有关。品种“月光”对任何镰刀菌菌株引起的FSB或FHB以及病原体DNA、ENNs或BEA的积累均比“淬火”具有显著更高的抗性。总之，侵染力强的燕麦镰孢菌菌株是强效的ENN产生菌，可导致严重的FSB和FHB，其中ENN A1作为谷物中燕麦镰孢菌潜在毒力因子需要进一步研究。
