10个切花菊品种耐旱性评价及耐旱生理机制探讨

Evaluation of drought tolerance and corresponding exploration of the physiological mechanism of ten cut Chrysanthemum

通过幼苗期自然失水胁迫划分萎蔫指数,并对10个切花菊品种苗期耐旱性进行评价以及对典型耐旱和不耐旱品种叶片失水速率、根冠比、电导率、丙二醛含量、超氧化物歧化酶(SOD)活性等形态和生理指标进行测定分析,探讨其耐旱生理机制。结果表明:在供试的10个品种中最耐旱的是南京红雀,最不耐旱的是南农粉樱;耐旱品种叶片失水速率较慢、根冠比较大,干旱胁迫使叶片电导率、丙二醛含量、SOD活性均上升,耐旱品种与非耐旱品种各项指标变化率有显著差异。叶片失水速率、根冠比、电导率、丙二醛含量、SOD活性可以作为切花菊耐旱性评价的指标。

The drought tolerance of ten cultivars of cut chrysanthemum was evaluated in this study through wilting index （WI） divided by means of natural water loss stress at their seedling stage. The morphological and physiological indicators, such as the water loss rate of leaves, the root-shoot ratio, the electric conductivity, MDA content and the activity of SOD, were measured in order to explore the physiological mechanism of drought tolerance. The results indicated that the most drought-tolerant cuttivar Nanjing Hongque displayed lower water loss rate of leaves and higher root- shoot ratio. The electric conductivity in leaves, the MDA content and the activity of SOD increased under the drought stress. Among cultivars evaluated, Nannong Fenying had the least drought tolerance. There were significant differences in each indicator between the drought-tolerant and the non-tolerant cultivars. Therefore, the water loss rate of leaves, the root-shoot ratio, the electric conductivity, the MDA content and the activity of SOD can be used as the indicators of evaluation of drought tolerance in Cut Chrysanthemum.