PDF(Pubmed)
Abstract：
Fusarium head blight (FHB) is a destructive disease caused by several species of Fusarium, such as Fusarium graminearum and F. asiaticum. FHB affects cereal crops, including wheat, barley, and rice, worldwide. Fusarium-infected kernels not only cause reduced yields but also cause quality loss by producing mycotoxins, such as trichothecenes and zearalenone, which are toxic to animals and humans. For decades, chemical fungicides have been used to control FHB because of their convenience and high control efficacy. However, the prolonged use of chemical fungicides has caused adverse effects, including the emergence of drug resistance to pathogens and environmental pollution. Biological control is considered one of the most promising alternatives to chemicals and can be used for integrated management of FHB due to the rare possibility of environment pollution and reduced health risks. In this study, Bacillus velezensis JCK-7158 isolated from rice was selected as an ecofriendly alternative to chemical fungicides for the management of FHB. JCK-7158 produced the extracellular enzymes protease, chitinase, gelatinase, and cellulase; the plant growth hormone indole-3-acetic acid; and the 2,3-butanediol precursor acetoin. Moreover, JCK-7158 exhibited broad antagonistic activity against various phytopathogenic fungi and produced iturin A, surfactin, and volatile substances as active antifungal compounds. It also enhanced the expression of PR1, a known induced resistance marker gene, in transgenic Arabidopsis plants expressing β-glucuronidase (GUS) fused with the PR1 promoter. Under greenhouse conditions, treatments with the culture broth and suspension concentrate formulation of JCK-7158 at a 1,000-fold dilution inhibited the development of FHB by 50 and 66%, respectively. In a field experiment, treatment with the suspension concentrate formulation of JCK-7158 at a 1,000-fold dilution effectively controlled the development of FHB with a control value of 55% and reduced the production of the mycotoxin nivalenol by 40%. Interestingly, treatment with JCK-7158 enhanced the expression of plant defense-related genes in salicylic acid, jasmonic acid, ethylene, and reactive oxygen species (ROS) signaling pathways before and after FHB pathogen inoculation. Taken together, our findings support that JCK-7158 has the potential to serve as a new biocontrol agent for the management of FHB.
摘要：
镰刀菌枯萎病（FHB）是由几种镰刀菌引起的破坏性疾病，如镰刀菌和亚洲镰刀菌。FHB影响谷类作物，包括小麦,大麦,还有米饭,全世界。镰刀菌感染的谷粒不仅导致产量降低，而且通过产生霉菌毒素而导致质量损失，如单孢霉烯和玉米赤霉烯酮，对动物和人类都有毒。几十年来,化学杀真菌剂由于其方便和高控制效力而被用于控制FHB。然而,化学杀菌剂的长期使用造成了不良影响，包括对病原体的耐药性和环境污染的出现。生物控制被认为是最有前途的化学品替代品之一，由于罕见的环境污染和降低的健康风险，可用于FHB的综合管理。在这项研究中,选择从水稻中分离出的VelezensisJCK-7158作为化学杀菌剂的生态替代品，用于管理FHB。JCK-7158产生的胞外酶蛋白酶，几丁质酶，明胶酶,和纤维素酶；植物生长激素吲哚-3-乙酸；和2,3-丁二醇前体丙酮。此外，JCK-7158对各种植物病原性真菌表现出广泛的拮抗活性，并产生iturinA，surfactin,和挥发性物质作为活性抗真菌化合物。它还增强了已知的诱导抗性标记基因PR1的表达，在表达与PR1启动子融合的β-葡糖醛酸糖苷酶（GUS）的转基因拟南芥植物中。在温室条件下，以1,000倍稀释的JCK-7158的培养肉汤和悬浮浓缩制剂的处理将FHB的发展抑制了50％和66％，分别。在现场实验中，以1,000倍稀释的JCK-7158的悬浮浓缩制剂处理有效地控制了FHB的发展，控制值为55％，并将霉菌毒素雪腐镰刀菌烯醇的产生减少了40％。有趣的是,用JCK-7158处理可增强植物防御相关基因在水杨酸中的表达,茉莉酸,乙烯,FHB病原体接种前后的活性氧（ROS）信号通路。一起来看,我们的研究结果支持JCK-7158有潜力作为一种新的生物控制剂用于FHB的管理。
