Virulence of Fusaric Acid and Rude Extract of Fusarium oxysporum on Cotton

[Objective] The aim was to study wilt-produced effect of fusaric acid and culture liquid on cotton diseased varieties and resistant conversion strains.[Method] Cotton seeds and seedlings of different resistance varieties were incubated within FA and rude extract of the different concentrations and time.The virulence of two toxins was evaluated adding to germination rate of seeds and incidence of seedlings,respectively.[Result] In 25% culture liquid,the concentration of fusaric acid is 21.46 μg/ml,its inhibition rate of seed germination is lower than 30.00 μg/ml.In 50% culture liquid,the concentration of fusaric acid is 30.62 μg/ml,its inhibition rate of seed germination is the same with 50.00 μg/ml.With the extending of incubating time and dose of extract,the disease index of cotton seedlings increase.[Conclusion] The virulence of rude extract of Fusarium oxysporum is stronger than fusaric acid on cotton seeds and seedlings.