Sun Zihao, Hao Baihui, Wang Cuicui, Li Shiyu, Xu Yuxin, Li Baohua, Wang Caixia
Shandong Engineering Research Center for Environment-Friendly Agricultural Pest Management, Shandong Province Key Laboratory of Applied Mycology, College of Plant Health and Medicine, Qingdao Agricultural University, Qingdao, Shandong, China.
Shandong Provincial University Laboratory for Protected Horticulture, Shandong Facility Horticulture Bioengineering Research Center, Weifang University of Science and Technology, Weifang, Shandong, China.
Front Microbiol. 2023 Mar 2;14:1131737. doi: 10.3389/fmicb.2023.1131737. eCollection 2023.
Apple ring rot caused by is an important disease that leads to severe quality deterioration and yield loss at pre-harvest and postharvest stages. Therefore, it is urgent to develop safe and efficient measures to control this disease. The objective of the present study was to investigate the biocontrol features of B-1 against and explore its mechanism of action utilizing and assays. The results showed that B-1 strongly reduced the incidence of apple ring rot and lesion diameter by 41.2 and 90.2%, respectively, in comparison to the control fruit. In addition, the control efficiency of strain B-1 against infection depended on its concentration and the interval time. B-1 cells showed higher inhibitory activities than its culture filtrates on the mycelial growth and spore germination of . Moreover, B-1 treatment alleviated electrolyte leakage, lipid peroxidation, and HO accumulation in -infected apple fruit by increasing antioxidant enzyme activities, including peroxidase, catalase, superoxide dismutase, and ascorbate peroxidase. We also found that strain B-1 treatment enhanced four defense-related enzyme activities and stimulated the accumulation of three disease-resistant substances including phenolics, lignin, and salicylic acid (SA) in apple fruit. In addition, strain B-1 triggered the upregulated expression of defense-related genes such as PR genes (, , , and ) and two genes involved in the biosynthesis of SA ( and ) to promote the resistance potential in apple fruit. Hence, our results suggest that B-1 is a promising strategy against , mainly through reducing oxidative damage, activating defense-related enzymes, accumulating disease-resistant substances, and triggering the expression of resistance-correlated genes in apple fruit.
由[病原体名称未给出]引起的苹果轮纹病是一种重要病害，在采前和采后阶段都会导致严重的品质劣化和产量损失。因此，迫切需要制定安全有效的措施来控制这种病害。本研究的目的是研究[菌株名称未给出]B-1对[病原体名称未给出]的生防特性，并利用[检测方法未给出]和[检测方法未给出]分析其作用机制。结果表明，与对照果实相比，B-1使苹果轮纹病的发病率和病斑直径分别显著降低了41.2%和90.2%。此外，菌株B-1对[病原体名称未给出]感染的防治效果取决于其浓度和间隔时间。B-1细胞对[病原体名称未给出]的菌丝生长和孢子萌发的抑制活性高于其培养滤液。此外，B-1处理通过提高包括过氧化物酶、过氧化氢酶、超氧化物歧化酶和抗坏血酸过氧化物酶在内的抗氧化酶活性，减轻了[病原体名称未给出]感染苹果果实中的电解质渗漏、脂质过氧化和HO积累。我们还发现，菌株B-1处理增强了苹果果实中四种防御相关酶的活性，并刺激了包括酚类、木质素和水杨酸（SA）在内的三种抗病物质的积累。此外，菌株B-1触发了防御相关基因如PR基因（[基因名称未给出]、[基因名称未给出]、[基因名称未给出]和[基因名称未给出]）以及参与SA生物合成的两个基因（[基因名称未给出]和[基因名称未给出]）的上调表达，以提高苹果果实的抗性潜力。因此，我们的结果表明，[菌株名称未给出]B-1是防治[病原体名称未给出]的一种有前景的策略，主要通过减少氧化损伤、激活防御相关酶、积累抗病物质以及触发苹果果实中抗性相关基因的表达来实现。
