Studies On The Effective Component Against Watermelon Fusarium Wilt From Tagetes Root Extract

This research is about the effective component against watermelon Fusarium wilt from Tagetes root extract that was extracted by different solvents, isolated and purified by thin-layer chromatography, column chromatography, GC and GC/MS and some biochemical methods. Every components of extract was identifed the bioactivity and chosed the best one. Finally a component with the greatest bioactivity against Fusariwn wilt was found. Then with the GC/MS and GC analysis the structure of the component could be determined. The results indicated:1 .Using different solvent to extract effective components from powder of Tagetes root with supersonic and heated water. Every extract was tested by bioactivity against watermelon Fusarium wilt. The results showed that every extract had some inhibiting effects on watermelon Fusarium wilt; The most effective extract was extracted by aether which would be isolated and purified by the following process; The chloroform extract was much more than other one. The color of extract by NaOH was much different from other extract and had no effect on watermelon Fusarium wilt.2. Isolated and purified the aether extract by column chromatography: First using the different polar solvent to build many solvent compounds; then identifmg the best effective solvent combination tested by thin-layer chromatography. Finally choosing the chloroform as the best one for column chromatography, by which the aether extract was isolated to four parts and with the bioactivity tests, the Part Ⅲ was chosed as the best one against watermelon Fusarium wilt. According to the research of Xin-guo Wang about Tagetes chemical components, did some character experiments about alkaloid, essential oil, flavone, patuletrin and mensurated the extractive efficiency of the four matters from Part Ⅲ, and with the bioactivity tests the result idicated that the main component of Part　Ⅲ was essential oil then analysed its components by GC/MS.3. Isolated the Part Ⅲ to six components with the common chemical method of essential oil, according the bioactivity tests, the oil part is the most effective one which was isolated to three fractions by column chromatography and thin-layer chromatography. With the bioactivity tests the fraction Ⅱ of oil part was the best one, then analysed its components with GC. Finally compared with the GC/MS of Part Ⅲ, the greatest bioactive compound was identified.4. According to the bioactivity of Part Ⅲ against some other common pathogen and spore bourgeon, and with the results mentioned above, this research can draw some conclusions: The main component of Tagetes root extract is essential oil; The extract of Tagetes root has many bioactive components against watermelon Fusarium wilt and spore bourgeon; In addition, the extract of Tagetes root has broad-spectrum inhibiting effect on Fusarium wilt.