香蕉枯萎病菌粗毒素的毒性及其模型

The Toxicity of the Crude Toxin of Fusarium oxysporum f. sp. cubense and Its Model

以香蕉组织培养苗为受试植物,蕉苗受毒素作用后的病情指数为指标,测定香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)粗毒素对蕉苗的毒性.结果表明,毒素处理72,96,120和144 h引致香蕉苗受害程度(以病情指数表示)达90的剂量(TD90)的质量浓度分别为2 057.20,1 245.49,549.54,380.19 μg/mL,蕉苗的受害程度存在着随处理时间延长和处理剂量的增加而加重的趋势.根据毒素对蕉苗的毒性测定结果,建立了蕉苗受毒素作用的'时间-剂量-受害程度'模型.根据模型的分析结果认为,粗毒素引致蕉苗受害的有效时间为96～120 h,有效剂量质量浓度为260.0～130.0 μg/mL.

The toxicity of the crude toxin of Fusarium oxysporum f. sp. Cubense to the banana plantlets was tested using the disease index as toxic degree.The results showed that the dose of causing toxic degree (TD 90) to the banana plantlets treated with the crude toxin for 72,96,120,144 h were 2 057.20,1 245.49,549.54 and 380.19 μg mL,respectively.The toxicity of the crude toxin to the banana plantlets changed with treated time and dose. The ″time-dose-toxic degree″ model was established according to the results of the toxin bioassay.It is suggested that the effective dose were 260.0～130.0 μg mL and the effective time were 96～120 h with the crude toxin treated the banana plantlets on the basis of the mode analysis.