木论保护区野生兜兰致病菌的分离鉴定及抑菌试验

Isolation, Identification and Bacteriostatic Test of Pathogenic Bacteria of Wild Paphiopedilum in Mulun Nature Reserve of Guangxi

摘要: 为了解桂西北岩溶地区野生兜兰致病菌的危害，以便为珍稀野生植物的生物学保育提供科学依据，对广西木论国家级自然保护区野生兜兰进行了实地调查，以具有典型白色病斑的硬叶兜兰叶片为实验材料，经过致病菌分离纯化、致病性测定、形态学鉴定及DNA测序，最终确认硬叶兜兰的病原菌为灰黄青霉(Penicillium griseofulvum)。为了筛选能够有效抑制该病原菌的天然植物材料，选用生姜、大蒜、洋葱三种天然植物的提取液进行了抑菌试验。结果表明，三种植物材料均对硬叶兜兰病原菌灰黄青霉具有抑制作用，其中大蒜提取液的抑菌作用最强，抑制率高达96%，说明大蒜具有防控硬叶兜兰病害的应用潜力。以天然植物提取液作为抑菌剂用于珍稀野生植物的生物学保育，可以节能减排，降低成本，保护环境。

Abstract: In order to understand the hazard of pathogenic bacteria in the karst area of northwest Guangxi, and to provide scientific basis for biological conservation of rare wild plants, field investigation was carried out on the wild Paphiopedilum in the Mudun National Nature Reserve of Guangxi. The leaves of P. micranthum with typical white lesions were used as experimental materials. After isolation and purification of pathogenic bacteria, pathogenicity determination, morphological identification and DNA sequencing, the pathogen of P. micranthum was finally confirmed to be Penicillium griseofulvum strain. In order to screen the natural plant materials that can effectively inhibit the pathogenic bacteria, the antibacterial test was carried out with the extracts of three natural plants, ginger, garlic and onion. The results showed that the three plant materials all had inhibitory effects on the pathogenic bacteria Penicillium griseofulvum, a pathogen of P. micranthum. Among them, the antibacterial effect of garlic extract was the strongest, and the inhibition rate was as high as 96%, indicating that garlic has the application potential of preventing and controlling the disease of P. micranthum. Using natural plant extracts as bacteriostatic agents for the biological conservation of rare wild plants can save energy, reduce costs, and protect the environment.