夏季水淹处理对疏花水柏枝恢复生长过程非结构性碳水化合物代谢的作用

Effects of Summer Flooding on Non-structural Carbohydrate Metabolism During Recovery of Myricaria laxiflora

摘要:

濒危植物疏花水柏枝(Myricaria laxiflora)残存种群每年夏季都要经历长时间的水淹，为揭示夏季水淹对其恢复生长的作用，设置不同夏季水淹时间(10、50、90 d)和水淹深度(根淹、半淹、全淹)的处理组合，测定疏花水柏枝植株在恢复生长过程中非结构性碳水化合物(NSC)含量及其相关代谢酶活性的变化。结果表明，夏季水淹能显著增加植株恢复生长初期的NSC及其各成分含量，但处理效应随着恢复生长进程逐渐减少。水淹还能显著增加植株在整个恢复生长期与NSC代谢相关的中性转化酶、蔗糖酸性转化酶、果糖-1,6-二磷酸醛缩酶和果糖-1,6-二磷酸磷酸转移酶的活性，并显著降低蔗糖磷酸合成酶的活性。相关性分析表明植株NSC及其各成分含量的变化与各相关代谢酶分别存在不同程度的显著相关性。进一步的主成分分析表明，夏季水淹诱导了植株恢复生长期NSC代谢的分化。水淹促使植株的NSC代谢在恢复生长初期向高可溶性糖含量分化，而对照组(不进行水淹)植株的NSC代谢则向低可溶性糖含量分化。因此，夏季水淹能提高植株恢复生长初期的NSC代谢生理，促进植株恢复生长。

Abstract:

The endangered plant Myricaria laxiflora experiences prolonged flooding every summer. To reveal the effect of summer flooding on its recovery growth, different combinations of flooding durations (10, 50, and 90 days) and flooding depths (root flooding, half flooding, and full flooding) were set up. The changes in non- structural carbohydrate (NSC) content and the activities of related metabolic enzymes during the recovery growth of M. laxiflora were measured. The results showed that summer flooding significantly increased the NSC content and its components at the early stage of recovery growth, but the treatment effect gradually decreased with the progress of recovery growth. Flooding also significantly increased the activities of neutral invertase, acid invertase, fructose-1,6-bisphosphate aldolase, and fructose-1,6-bisphosphate phosphotransferase related to NSC metabolism throughout the recovery growth period, while significantly reducing the activity of sucrose phosphate synthase. Correlation analysis indicated that the changes in NSC content and its components were significantly correlated with the activities of related metabolic enzymes to varying degrees. Further principal component analysis showed that summer flooding induced the differentiation of NSC metabolism during the recovery growth period. Flooding promoted the differentiation of NSC metabolism towards high soluble sugar content at the early stage of recovery growth, while the NSC metabolism of the control group (without flooding) differentiated towards low soluble sugar content. Therefore, summer flooding can enhance the NSC metabolism physiology at the early stage of recovery growth and promote the recovery growth of the plant.