干旱对银杏生理生化特性及叶绿体超微结构的影响

Effects of Drought on Physiological and Biochemical Characteristics of Leaves and Ultrastructure of Chloroplasts in Ginkgo biloba L.

以五年生盆栽的银杏大佛指实生苗为实验材料,通过持续自然干旱,研究了持续干旱条件下银杏叶片生理生化指标和叶绿体超微结构的变化.结果表明:干旱处理30 d后,银杏叶片叶绿素含量逐渐下降;MDA含量和SOD活力逐渐上升,CAT活力逐渐下降;脯氨酸和可溶性糖含量逐渐上升,可溶性蛋白质呈先下降后上升的趋势;各项生理指标(除SOD外)均与对照有显著差异(p<0.05).叶绿体逐渐膨胀变圆,基质片层膨胀溶解,嗜锇颗粒增大增多,最终破裂解体.说明持续30d的干旱,对银杏叶片各项生理指标和叶绿体超微结构未产生显著影响,银杏有一定抵御干旱的能力.

5 year-old Ginkgo biloba L.seedlings was selected to measure the changes in physiological and biochemical indexes of leaves and ultrastructure of chloroplasts under prolonged drought stress.The results show that chloroplasts（Chl） content decreased when the drought stress had lasted 30 days,while MDA content and the activities of SOD increased,which resulted in the reduction of the activities of CAT.At the same time,proline and soluble sugar content were gradually increased,while content of soluble protein decreased at first and then increased again.There were significant differences in every physiology indexes with the control except the activities of SOD.Chloroplast lamellae became loose gradually,whereas the number and size of osmiophilic granule increased during drought stress till the chloroplast disappeared.There were no variations in some physiological indexes for the Ginkgo biloba L.leaves and chloroplast ulrastructure under drought stress for 30 d.So Ginkgo biloba L.has some adaptation for drought.