The present invention employs the ethanol-water (70:30) extracts of coptis chinensis for antibacterial activity tests on rhizoctonia solani and fusarium. The result shows that it has the inhibition effect above 80%. The extraction method employs the hot reflux of ethanol-water under 100 degree C for 8 hours. The coptis chinensis extracts may be used as plant protection agent for soil borne crop disease prevention. The present invention may be further added with rhubarb, tuckahoe and paeonia lactiflora extracts or further contain anti-fungous agent, pesticide, herbicide and antibacterial agent in combination to compose the plant protection formulation.本發明為利用黃連(Coptis chinensis)的乙醇-水(70:30)萃取物對於立枯絲核菌與鐮胞菌進行抑菌活性測試,結果發現具有80%以上的抑制效果。萃取方法,為利用乙醇水熱迴流100℃、8小時萃取,黃連萃取物可作為防治作物土傳性病害的植物保護劑,甚至可更進一步添加大黃、茯苓及白芍萃取物,或是可更進一步包含抗真菌劑、殺蟲劑、除草劑與抗菌劑搭配使用,以組成植物保護製劑。
