不同基因型香蕉对钾高效吸收的根系形态学和生理学特征

利用Hoagland营养液培养,设计0.25 mmol/L(低钾)、2.5 mmol/L(高钾)2种水平,初步探讨4个不同基因型香蕉对低钾适应性。结果表明:钾高效品种在根系活跃吸收面积,总吸收面积,比表面积、及根系活力大于钾低效品种。钾高效香蕉品种根系吸收钾的Km值、Cmin都小于钾低效品种,而Imax和a值普遍大于钾低效品种,钾高效品种在低钾胁迫下通过提高丙二醛、可溶性蛋白含量和SOD酶活性实现钾素利用的保护性反应,具有较强的自我保护能力。

Difference in Morpholofical and Physiological Characters of Banana Varieties to Potassium

Four different genotypes of banana on low potassium adaptation were treated with Hoagland nutrient solution culture with 0.25 mmol/L potassium(low level), 2.5 mmol/L potassium(high level). The results showed that: Root active absorption area, total absorption area, surface area, and root activity were greater in K efficient cultivars than those in K-inefficient cultivar; Km values and Cmin, were less for efficient cultivars than those for K-inefficient cultivar, while Imax and A value were greater than hose for K-inefficient cultivar; potassium efficient cultivar under low potassium stress responded by increasing MDA, soluble protein content and SOD activity to achieve a protective response to the use of potassium.