干旱胁迫对不同烤烟品种根系生长和生理特性的影响

以抗旱型烤烟品种‘农大202'及一般型烤烟品种‘NC89'和‘K326'为材料,采用盆栽试验研究了干旱胁迫对根系生长和生理特性的影响,以明确各烟草品种的抗旱能力及其与根系生长和生理特性的关系.结果显示:严重干旱胁迫之后各烤烟品种根系鲜重、干重上升,而根系活力、根系吸收面积以及根系SOD和POD活性等根系生理指标则呈下降趋势.在干旱胁迫条件下,‘农大202'的根系总吸收面积、活跃吸收面积、根系活力、SOD活性和POD活性均显著高于两对照品种‘NC89'和‘K326',但其根系鲜重和干重等生物量并不具有太大的优势.研究表明,烟草的根系生长和生理特性对环境水分条件的响应存在明显的基因型差异;在干旱胁迫条件下, ‘农大202'根系能保持较高总吸收面积、活跃吸收面积、根系活力和保护酶活性,是其具有较强抗旱性的生理基础.

Growth and Physiological Characteristics of Roots in Different Flue-cured Tobacco Varieties under Drought Stress

The experiment were carried out to study the effects of drought stress on growth and physiological characteristics of roots among three stress,the root biomass including root fresh weight and root dry weight increased,whereas,the root activity,root absorbing area,SOD activity and appeared significantly greater root total absorbing area,active absorbing area,SOD activity and POD activity,but the root biomass including fresh weight and dry weight did not have significant difference.In conclusion,there are obvious differences among flue-cured tobacco genotypes in root growth and physiological characteristics,and their activity and POD activity,more root total and active absorbing area under seriously drought stress,which were the physiological basis of stronger drought resistance.