樟属植物芳樟、龙脑樟精油微胶囊化制备及其对镰刀菌的抑制机理研究

Fusarium spp. can cause Fusarium wilt, which seriously affects crop production. Fusantium mycotoxins can pollute animal feed and human food and thereby has great threat on human health. To control plant diseases caused by Fusarium spp., the use of chemical pesticides produces pesticide residues and environmental pollution. Therefore, it is of great significance to find the effective, low-toxicity and environment-friendly inhibitors against Fusarium spp. to replace traditional chemical pesticides. The present project selects five Fusarium spp. strains as the study object, extracts essential oils from the barks and leaves of C. camphora and C. camphora chvar. Borneol and followed by preparing the essential oil microcapsules. The inhibition activity of the prepared essential oil microcapsules against five Fusarium spp. strains was investigated. To explain the inhibition mechanism of essential oils on the inhibition of Fusarium spp., scanning electron microscopy, transmission electron microscopy, flow cytometry, transcriptome sequencing and real-time fluorescence quantitative PCR, two dimensional electrophoresis, infrared spectroscopy and Raman spectroscopy were employed to analyze the effect of essential oils on mycelia morphologies, cells growing, differential gene expression, protein changing, and cell membrane and lipid synthesis of five Fusarium spp. strains. This study not only proposes new thoughts for the efficient use of essential oils of C. camphora and C. camphora chvar. Borneol, but also provides scientific foundation for finding the plant-derived and new natural pesticides, which have the great potential on replacing traditional chemicals to prevent the plant diseases caused by Fusarium spp.

镰刀菌引起的植物枯萎病严重影响农作物的生产，镰刀菌产生的毒素通过污染动物饲料和食物进而对人类健康造成巨大威胁。采用化学农药防治镰刀菌引起的植物病害存在农药残留以及污染环境等问题。因而，找到能够替代传统化学农药的高效、低毒、环境友好的镰刀菌抑制剂具有十分重要的研究意义。项目选择对农林作物危害严重的5种镰刀菌为研究对象，以芳樟、龙脑樟的树皮和树叶为原料分离精油并制备精油微胶囊，评价芳樟、龙脑樟精油对镰刀菌的抑制作用。应用扫描电镜、透射电镜、流式细胞仪、转录组测序、荧光定量、双向凝胶电泳技术、红外光谱以及拉曼光谱分析精油对镰刀菌形貌、细胞生长、差异基因表达、蛋白质变化以及细胞膜和细胞脂质合成的影响，进而阐明精油抑制镰刀菌的机理。项目的开展不仅为芳樟、龙脑樟精油的高效利用提供新思路，也为寻找植物源、新型、具有替代传统化学农药潜力的用于防治由镰刀菌引起植物病害的天然农药提供科学依据。

镰刀菌引起的作物枯萎病严重影响农作物的生产，镰刀菌产生的毒素通过污染动物饲料和食物进而对人类健康造成巨大威胁。采用化学农药防治镰刀菌引起的植物病害存在农药残留以及污染环境等问题。植物精油用于作物病虫害防治具有广阔的应用前景。项目采用微波辐照法从樟属植物芳樟和龙脑樟等植物中高效提取得到了精油，对精油的组成进行分析比较。采用复凝聚法和包合法制备得到了精油微胶囊，对精油的制备过程加以优化，同时采用扫描电镜、热重分析、傅里叶红外光谱等技术对制备得到的精油微胶囊的组成进行表征，研究发现精油成功的被壁材包埋，而且具有很好的热稳定性和缓释型，红外光谱结果表明微胶囊化处理前后没有对精油的 组成造成明显的影响。研究了芳樟和龙脑樟植物精油对5种马铃薯干腐病镰刀菌的抑菌活性，研究结果表明芳樟和龙脑樟精油对马铃薯干腐病主要病原菌表现出明显的抑制作用，主要是因为精油含有丰富的萜类成分，可以破坏其细胞膜，破坏细胞通透性，阻断细胞增殖进而抑制镰刀菌的菌丝的生长和孢子的萌发。