香蕉枯萎病菌4号生理小种毒素解毒剂的筛选及对香蕉防御酶活性的影响

从15种候选解毒剂中筛选出对香蕉枯萎病菌(Fusarium oxysporum f.sp.cubense)4号生理小种(简称Foc 4)毒素解毒效果最好的2种解毒剂——硫酸锌和井冈霉素。在2 g.L-1浓度下,硫酸锌和井冈霉素对Foc 4毒素的钝化率分别为76.67%和71.33%,而在5 g.L-1浓度下,它们的钝化率分别为90.33%和80.00%。探索了毒素—硫酸锌和毒素—井冈霉素处理体系在2 g.L-1和5 g.L-1浓度下对香蕉苗5种防御酶(PAL、POD、PPO、SOD和CAT)活性的影响。结果表明,在这个处理体系中,香蕉苗PAL和PPO酶活高峰出现的时间(PAL 36 h、PPO 36 h和48 h)较毒素单独处理(PAL 48 h、PPO 60 h)早;SOD和CAT酶活高峰出现的时间与对照基本一致;而POD酶活高峰出现的时间较复杂。总体上,这个处理体系的酶活高于毒素单独处理和无菌水对照。"毒素—硫酸锌处理体系"在PAL、SOD整体酶活上高于"毒素—井冈霉素处理体系",而后者在其他3种酶活上普遍高于前者。

Screening of antidotes to toxin produced by Fusarium oxysporum f.sp.cubense race 4 and their effects on defensive enzyme activities of banana

Two best antidotes,zinc sulfate and Jinggangmycin,to toxin of Fusarium oxysporum f.sp.cubense race 4(Foc 4) were screened out from 15 candidates.It was found that the inhibitory rates of zinc sulfate and Jinggangmycin at concentration of 2 g·L-1 to Foc.toxin were 76.67% and 71.33%,respectively;while those at concentration of 5 g·L-1 were 90.33% and 80.00%,respectively.The effects of toxin-zinc sulfate and toxin-Jinggangmycin treatment systems at concentrations of 2 g·L-1 and 5 g·L-1 on the activities of five defensive enzymes(PAL,POD,PPO,SOD and CAT) in banana plantlets were explored,the results showed that the peaks of PAL and PPO activities in banana plantlets appeared earlier(PAL 36 h,PPO 36 h and 48 h) in the treatment systems than in toxin alone treatment(PAL 48 h,PPO 60 h);the peaks of SOD and CAT activities were basically consistent with those of control;and the peaks of POD activity were more complicated.Generally,the overall activities of defensive enzymes were higher in the treatment systems than in toxin alone treatment and sterile water control.The overall activities of PAL and SOD in toxin-zinc sulfate treatment system were higher than those in toxin-Jinggangmycin treatment system,whereas the activities of other three defensive enzymes of the latter were higher than those of the former.