【摘要】 以不同浓度Ca2+对干旱胁迫处理下的忍冬进行化学调控,研究外源Ca2+对干旱胁迫处理下忍冬叶片中叶绿素含量、可溶性糖含量、游离脯氨酸含量、过氧化氢酶活性以及光合速率的影响,以探讨外源Ca2+对缓解干旱胁迫下忍冬光合作用下降的作用机制。结果表明,干旱胁迫下,忍冬的正常生理代谢明显受到抑制,叶绿素质量分数、可溶性糖质量分数、游离脯氨酸质量分数、过氧化氢酶活性以及光合速率分别降低到0.4 mg·g-1、0.06~0.1 mg·g-1、0.8 mg·g-1、0.25 u.mg-1和12~14μmol·m-2.s-1;当施入钙离子后,干旱胁迫对忍冬的伤害得到不同程度的缓解,并在最大程度上稳定叶绿素含量和CAT活性;并能使脯氨酸和可溶性糖的积累显著减少。说明外源Ca2+能够在一定程度上弥补干旱胁迫导致的Ca2+亏缺,使植物维持较正常的生理活动,稳定细胞膜结构,维持体内离子吸收平衡,维持较高的光合速率并保护光合结构。更多还原

【Abstract】 Lonicera japonica Thunb is an important special with high drought resistance planted at karst area in Southwestern China.However,drought stress how to limit Lonicera japonica Thunb’s photosynthetic characteristics is not clear.A series pot-cultivation experiments were performed to investigate the effects of exogenous calcium on chlorophyll content,soluble sugar content,proline content,and photosynthetic rate of Lonicera japonica Thunb under drought stress,with the possible action mechanisms of Ca2+ discussed.Due to the drought stress effect,the content of chlorophyll,soluble sugar,proline,catalase enzyme activity and photosynthetic characteristics in Lonicera japonica fall to 0.4 mg·g-1,0.06-0.1 mg·g-1,0.8 mg·g-1,0.25 u·mg-1 and 12-14 μmol·m-2·s-1 respectively.However,when soil pre-treatment with the suitable Ca2+ concentration during drought stress,it will increase catalase enzyme activity and chlorophyll content,which will alleviate cell membrane leakage and chlorophyll decomposition.Moreover,proline content and soluble sugar content will decrease compared with the results without soil pre-treatment with the suitable Ca2+ concentration.更多还原