钠盐与AT毒素对烟苗根生长的影响

Effects of sodium compound and AT toxin on root length of tobacco seedling

为确定不同钠盐对烟草赤星病菌AT毒素毒性的影响，作者采用摩擦接种处理、浇根处理、种子根处理3种生物测定方法，确定了以烟草种子根处理法作为烟草赤星病菌的毒性测定方法。用10种化合物分别以5种不同浓度与AT毒素混合接种烟苗，分别以单独接种毒素稀释液与无菌水作对照。根长测定数据经DPS软件统计分析，结果表明单独施用AT毒素明显抑制烟苗根的生长，差异极显著；氢氧化钠、硝酸钠、苯甲酸钠、酒石酸钠均不能改变毒素对根长的影响，碳酸钠（200mg／mL）、酒石酸钾钠（200mg／mL）、四硼酸钠（0．02-0．2mg／mL）、氟化钠（0．2～2mg／mL）、柠檬酸钠（0．2mg／mL-200mg／mL）、钼酸钠（0．02-2mg／mL）对烟草赤星病菌毒素有明显钝化作用，以钼酸钠0．02mg／mL浓度处理效果最好，其次为柠檬酸钠0．2mg／mL处理；钼酸钠20-200mg／mL处理可增加AT毒素的毒性，浓度越大效果越显著。

Ten sodium compounds each with 5 different concentrations were used to evaluate their effects on phytotoxin produced by Ahemaria alternata （GL-6） with the method of tobacco seed-root treatment. Root length determination results indicated that AT toxin can obviously restrain growth of tobacco seedling root. NaOH, NaNO3, C6H5COONa, KNaC4H4O6·4H2O did not influence AT toxin on root. However, there existed distinct restraint effect on root treated with the mixture of AT toxin and each compound such as Na2CO3 （200mg/mL）, C4HaO6Na2·2H2O （200mg/mL）, Na4B4O7·10H2O （0.02- 0.2mg/ mL）, NaF （0.2- 2mg/mL）, Na3C6H5O7.2H2O （0.2 - 200mg/mL） and Na6M7TO24 （0.02 - 2mg/mL）. The treatment of 0.02mg/mL of Na6Mo7O24 and toxin was better than any other treatment while concentration of 20- 200mg/mL of Na6Mo7O24 can aggravate the toxicity of AT toxin on tobacco seedling.