3种外源植物生长调节剂对干旱胁迫下烟草生理的影响

以K326品种烤烟为试验材料,采用盆栽试验研究干旱胁迫下烤烟生长与生理状况,以及喷施水杨酸、甜菜碱和氯化胆碱对烤烟抗氧化代谢影响。结果表明,干旱胁迫抑制烤烟正常生长,烟株矮小,有效叶片数目少,茎干瘦弱,叶长变短及叶宽变窄。喷施植物生长调节剂可以缓解干旱胁迫症状,喷施氯化胆碱能有效增加株高、最大叶长、有效叶片数,提高烟株干重、丙二醛(MDA)含量、脯氨酸含量及超氧化物歧化酶酶(SOD)活性;喷施甜菜碱对过氧化氢酶(CAT)活性有较好调节效应;喷施水杨酸能显著提高过氧化物酶(POD)活性,提高烤烟茎围和最大叶宽。综上所述,植物生长调节剂能提高烟株耐旱性,增强烟株对干旱环境适应性,其中以喷施氯化胆碱效果最佳。

Effects of three exogenous plant growth regulators on tobacco physiology under drought stress

The effects of salicylic acid, glycine betaine and choline chloride on the antioxidant metabolism of flue-cured tobacco were studied using a pot experiment. The growth and physiological indexes of flue-cured tobacco cultivar K326 under drought stress were studied. The results showed that drought stress inhibited the normal growth as the tobacco plants were shorter, the number of effective leaves were lessen, the stem was thinner, and the leaf length became shorter and the leaf width became narrower compared with the control. Spraying plant growth regulators could relieve the drought stress symptoms. For example, spraying choline chloride effectively increased the dry weight, MDA content, free proline content, SOD activity and it also effectively increased the plant height, the maximum leaf length and effective leaf number. Glycine betaine had a good regulatory effect on CAT activity. Spraying salicylic acid significantly increased POD activity, raised stem thickness and maximum leaf width. In summary, plant growth regulators can improve the drought tolerance of tobacco plants, and enhance the adaptability of tobacco plants to drought environment and choline chloride showed the best effect.