Loquat fruit is a subtropical fruit with high commercial values in the international market, but it actually has a short postharvest life due to mechanical damage and microbial decay. Until now, there exist few appropriate storage methods or biocontrol agents to control postharvest diseases and prolong storage period of postharvest loquat fruit. Recently, by comparing twelve Bacillus strains with biocontrol activity, a potential Bacillus amyloliquefaciens B4 was found to be effective in controlling various pathogens of loquat fruit. The in vivo results displayed that the active constituent in B4 exerting antifungal activity was bacterium itself, rather than metabolites. Scanning electron microscope was applied to observe the interaction between B4 and pathogens, and bacterial colonization and site occupancy on postharvest loquat fruit appeared to be one of the reasons why B4 could inhibit growth of fungal pathogens. In brief, Bacillus amyloliquefaciens B4 tends to be the most broad-spectrum antifungal biological agent available so far against postharvest pathogens of loquat fruit. Furthermore, oral toxicity test results suggested Bacillus B4 is actually non-toxic, making it a really suitable biocontrol agent for postharvest loquat fruit. The treatment for loquat fruit with B4 resulted in a lower disease incidence, with only 62.5 % compared to all decayed in the untreated group 20 d after inoculation at 25 ℃. This study provides a promising biological agent to control diseases of postharvest loquat fruit and improves our understanding of the possible biocontrol mechanisms of the Bacillus strain.

果是一种在国际市场上具有很高商业价值的亚热带水果，但由于机械损伤和微生物腐烂，它实际上具有较短的收获后寿命。迄今为止，很少有合适的贮藏方法或生物防治剂来控制采后病害并延长lo果实的贮藏期。最近，通过比较十二种具有生防活性的芽孢杆菌菌株，发现了潜在的解淀粉芽孢杆菌B4可有效地控制controlling果实的各种病原体。在体内结果表明，B4中发挥抗真菌活性的活性成分是细菌本身，而不是代谢产物。应用扫描电子显微镜观察B4与病原菌的相互作用，lo后果实上的细菌定植和定居是B4抑制真菌病原菌生长的原因之一。简而言之，解淀粉芽孢杆菌B4倾向于是迄今为止针对against果实采后病原体的最广谱抗真菌生物剂。此外，口服毒性试验结果提示芽孢杆菌B4实际上是无毒的，使其成为for后果实的真正合适的生物防治剂。用B4处理lo果实的病害发生率较低，在25℃接种20 d后，未处理组的病菌发病率只有62.5％。这项研究为控制a后果实的疾病提供了一种有前途的生物制剂，并增进了我们对芽孢杆菌菌株可能的生物防治机制的理解。