Khanal Raja, Hudson Kerin, Foster Adam, Wang Xiben, Brauer Elizabeth K, Witte Thomas E, Overy David P
Ottawa Research and Development Centre, Agriculture and Agri-Food Canada, Ottawa, ON K1A 0C6, Canada.
Charlottetown Research and Development Centre, Agriculture and Agri-Food Canada, Charlottetown, PE C1A 4N6, Canada.
J Fungi (Basel). 2024 Sep 26;10(10):670. doi: 10.3390/jof10100670.
Barley is the third most important cereal crop in terms of production in Canada, and Fusarium head blight (FHB) is one of the main fungal diseases of barley. FHB is caused by a species complex of Fusaria, of which Schwabe is the main causal species of FHB epidemics in Canada. Field surveys show that two or more species often co-exist within the same field or grain sample, and is reported as another important species in barley. This study aimed to determine the pathogenicity of , , and a co-inoculation of both species causing FHB in barley. Two susceptible barley cultivars were spray-inoculated at 10 to 14 days after heading. Phenotypic disease severity was rated on a scale of 0-9 at 4, 7, 14, 21, and 28 days after inoculation. There was a significant difference in FHB severity between and , where infection with produced more severe disease ratings. generated lower disease ratings and was not statistically different from the control. When heads were co-inoculated with both species, the resulting FHB severity was unchanged relative to heads inoculated with only. The ratio of to genomic DNA was also no different than when heads were inoculated with alone, as quantified with ddPCR using markers specific to each species. The metabolomic analysis of sample extracts showed that -associated metabolites dominated the mycotoxin profile of co-inoculated samples, which corroborated our other findings where appeared to outcompete in barley. No significant effect on visual FHB disease ratings or fungal DNA detection was observed between the cultivars tested. However, there were some metabolome differences between cultivars in response to the challenge by both and .
大麦是加拿大产量方面第三重要的谷类作物，而镰刀菌穗腐病（FHB）是大麦的主要真菌病害之一。FHB由镰孢菌属的一个复合种引起，其中Schwabe是加拿大FHB流行的主要致病种。田间调查表明，两个或更多物种常常在同一田地或谷物样本中共存，并且被报道为大麦中的另一个重要物种。本研究旨在确定、以及这两种引起大麦FHB的物种共同接种时的致病性。在抽穗后10至14天对两个感病大麦品种进行喷雾接种。在接种后4、7、14、21和28天，根据0 - 9级标准对表型病害严重程度进行评级。和之间的FHB严重程度存在显著差异，感染产生的病害评级更高。产生的病害评级较低，且与对照无统计学差异。当穗部同时接种这两种物种时，相对于仅接种的穗部，产生的FHB严重程度没有变化。使用针对每个物种的特异性标记通过ddPCR定量分析，与单独接种时相比，两种物种基因组DNA的比例也没有差异。样品提取物的代谢组学分析表明，与相关的代谢物在共同接种样品的霉菌毒素谱中占主导地位，这证实了我们的其他发现，即在大麦中似乎比更具竞争力。在所测试的品种之间，未观察到对视觉FHB病害评级或真菌DNA检测有显著影响。然而，在应对和的挑战时，品种之间存在一些代谢组差异。
