棉花黄萎病菌毒素的提取及其生物活性测定

为了明确棉花黄萎病菌毒素对棉花的致病能力,将发酵液离心除菌,用硫酸铵-丙酮协同沉淀法提取棉花黄萎菌毒素,并对毒素进行生物活性的测定。结果表明:用硫酸铵-丙酮协同沉淀法比传统的单独用硫酸铵沉淀提取的毒素浓度高,此毒素对棉苗有强烈的致萎作用,可对棉花叶片造成损伤,并抑制棉花种子的萌发,而且与浓度有密切关系,高浓度的致病力强,200倍的低浓度几乎无致病力。

Extraction and Bioassay of the Toxin Produced by Verticillium dahliae

In order to obtain the toxin from the fermentation broth of Verticillium dahliae,the separation technique was explored.The optimized process includes the following steps:removing cells by the centrifugation,ammonium sulfate and acetone precipitation and bioassaying the toxin.The result demonstrated that the cooperation of ammonium sulfate and acetone is better than only use ammonium sulfate,it can guarantee deposit almost all the protein from the fermentation broth.Bioassay results showed that the toxin cause wilt of seedlings and leave of cotton.Meanwile restrain the seed of cotton from burgeoning.There is affinitative between the nosogenesis and concentration.The high concentration has strong nosogenesis,the toxin has been diluted 200 × hardly has nonsogenesis.