甘薯根腐病病原菌粗毒素对甘薯生长的影响

Effect of crude toxin of Fusarium solani f.sp. batatas on the growth of sweet potato

本文鉴定了茄病镰孢甘薯专化型[Fusarium solani（Mart）Sacc．f．sp．batatas McClure，简称FSB]引起甘薯胜利百号根腐病以及诱导胜利百号显蕾开花，并研究了菌株V100—93-06粗毒素对胜利百号组培苗生长的影响。结果表明，菌株V100—93-06对不同甘薯栽培品种呈现不同的致病性，其粗毒素能够诱导甘薯出现和病原菌寄生相似的部分症状。粗毒素原液处理胜利百号薯苗2、3、5和9d，病情指数分别为0．9,2．8、2．5和3．0，而10倍稀释浓度的粗毒素处理2、3、5和9d，病情指数分别为0、1．5、2．8和2．5。1～1000倍稀释浓度的粗毒素处理胜利百号组培苗3h，就能够诱导出现黄叶，浓度越高诱导出现黄叶数越多；对基芽和根的影响则表现为抑制基芽和根的生长，浓度越高基芽和根的数量越少；对根伸长生长的影响表现为1倍稀释浓度粗毒素抑制根的伸长生长，10～1000倍稀释浓度都能够促进根的伸长生长。

Fusarium solani （Mart） Sacc. f. sp. batatas McClure （abbreviation as FSB） was identified to cause root rot and induce flowering of sweet potato Shenglibaihao. The effect of crude toxin of strain V100-93- 06 of FSB on the growth of sweet potato tissue culture seedlings was studied. The results showed that the virulence of V100-93-06 to different varieties varied, and its crude toxin resulted in similar symptoms as the fungal infection. The disease index of symptom of Shenglibaihao seedlings was 0.9, 2.8, 2.5 and 3.0 at 2^th, 3^th, 5^th, and 9^th d after treated with the crude toxin, and the disease index of symptom was 0, 1.5, 2.8 and 2.5 treated with 10 dilutions. When the seedlings of tissue culture of Shenglibaihao treated with 1 - 1 000 dilutions of crude toxin, yellow leaves were induced only in 3 h, and the high concentration of crude toxin was used, the more yellow leaves was got; the crude toxin inhibited the growth of the hypoblasts and roots, the number of the hypoblasts and roots was decreased as the crude toxin concentrations increased; 1 dilution inhibited the growth of the length of the roots, but the growth of the length of the roots was advanced when treated with 10 -1 000 dilutions.