茶树油粕水粗提物控制香蕉采后炭疽病害的研究

为探明茶树油粕提取物对香蕉采后主要病害炭疽病的防治作用,通过正交试验优化茶树油粕粗提物的水提取方法,并以茶皂素为对照,研究提取物对香蕉炭疽病菌离体生长和香蕉果实活体接种致病斑的作用效果。结果显示,以料液比1∶7（m∶V）,在85℃条件下,将干燥的茶树油粕浸提2～2.5 h,或95℃条件下浸提1.5 h,粗提物的提取率较高,可达50%以上。获得的水粗提物可抑制离体培养的香蕉炭疽病菌的生长,且浓度越高,抑制效果越明显,当浓度≥0.2 mg·mL-1时,抑制率可达100%;而其10倍浓度的茶皂素（2 mg·mL-1）才具100%的完全抑制效果。茶树油粕水粗提物处理香蕉果实后,可显著抑制活体接种果实炭疽病病斑的扩展,而同浓度的茶皂素没有明显抑制效果。初步研究表明,茶树油粕水粗提物对香蕉炭疽病菌的离体和活体控制效果显著优于茶皂素,说明粗提物中含有除茶皂素之外的抑菌活性组分,且起主要的抑菌作用。

Evaluation of Crude Water Extractum from Camellia semiserrata Chi Oil Residua to Control Banana Anthracnose Caused by Colletotrichum musae

In order to develop the use of Camellia semiserrata Chi oil residua on fruit postharvest disease controlling,extracting methods of water crude extractum was firstly screened and determined through an orthogonal experiment, then effects of the extractum on controlling Colletotrichum musa in vitro growth and in vivo anthracnose developing was investigated by taking tea saponin as control. Results revealed that the best extracting method, getting the higher extracting efficiency（the rate of extraction was above 50%）, was making material liquid ratio as 1∶7（m∶V）, then 2～2.5 hours for extraction process under 85 ℃, or 1.5 hours for extraction process under 95 ℃. Crude water extractum from Camellia semiserrata Chi oil residua under the above conditions could inhibit the in vitro growth of Colletotrichum musae, the inhibitory effects increase stronger with the increase of extractum concentration. Concentration at 0.2 mg·mL-1and above had a completely 100% inhibitory effect, while tea saponin at the concentration of 2 mg·mL-1could have the similar effects. Banana fruits treated with water crude extractum and inoculated by Colletotrichum musae showed decreased anthracnose disease development compared to non-treated water control, but fruits treated with tea saponin had no detected difference with the water control during storage. This results showed that effects in controlling in vitro Colletotrichum musae growth and in vivo disease development were much better than that of tea saponin, indicating other active antifungal components existing in the crude water extractum of Camellia semiserrata Chi oil residua except tea saponin and had the main inhibitory effect.