草业学报2018，Vol.27Issue(2)：48-56,9.DOI:10.11686/cyxb2017308
葡萄糖-6-磷酸脱氢酶在紫花苜蓿干旱耐受性中的响应
Role of glucose-6-phosphate dehydrogenase in the drought tolerance of alfalfa
摘要
Abstract
Glucose-6-phosphate dehydrogenase (G6PDH,EC1.1.1.49) is the first and critical rate-limiting enzyme in the pentose phosphate pathway.It is involved in the synthesis of NADPH and ribose-5-phosphate,and plays an important role in plant responses to biotic and abiotic stresses.The aim of this study was to explore the role of G6PDH under drought stress in alfalfa.First,7-day-old alfalfa seedlings were treated with different concentrations of polyethylene glycol (PEG),and then plant height and root length,fresh weight and dry weight,and the contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were determined.These analyses were used to define the concentration of PEG causing drought stress to the seedlings.Then,the activity of G6PDH in alfalfa seedlings was determined under a range of stress-inducing PEG concentrations.The G6PDH inhibitor Na3PO4 was applied to alfalfa seedlings under drought stress,and changes in the indexes described above were determined.The results showed that PEG treatment significantly inhibited the growth of alfalfa seedlings.Plant height,root length,fresh weight,and dry weight decreased with increasing PEG concentrations.Compared with non-stressed seedlings,those subjected to PEG-induced drought stress (15％ PEG) showed 28.4％ and 19.9％ higher contents of H2O2 and MDA,respectively,and 49.4％ lower G6PDH activity.Application of Na3PO4 decreased the activity of G6PDH and caused the symptoms of drought stress to become more severe,suggesting that G6PDH is involved in the regulation of oxidative stress induced by PEG.关键词
干旱胁迫/紫花苜蓿/丙二醛/过氧化氢/葡萄糖-6-磷酸脱氢酶Key words
drought stress/alfalfa (Medicago sativa)/malondialdehyde/hydrogen peroxide/glucose-6-phosphate dehydrogenase引用本文复制引用
熊丽丽,闫霜,李萍,杨国柱,尹卫,严晓霞,张韩..葡萄糖-6-磷酸脱氢酶在紫花苜蓿干旱耐受性中的响应[J].草业学报,2018,27(2):48-56,9.基金项目
国家自然基金地区基金项目(31660063),青海省科技厅基础研究计划(2016-ZJ-930Q),青海大学省部共建三江源生态与高原农牧业国家重点实验室开放课题(2017-KF-05)和青海大学生态环境工程学院中青年科研基金项目(2016-T-4)资助. （31660063）
