类黄酮参与调控中亚滨藜幼苗对盐胁迫的耐受性  

Flavonoid is associated with salt stress tolerance in Atriplex centralasiatica seedlings

作　　者：李爽[1,2] 孙亮亮[1,3] 白丽丽[1,4] 王文颖[4] 万金鹏[1] 刘小京[5] 马金虎[3] 徐进[1] LI Shuang;SUN Liangliang;BAI Lili;WANG Wenying;WAN Jinpeng;LIU Xiaojing;MA Jinhu;XU Jin(Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China;University of Chinese Academy of Sciences, Beijing 100049, China;College of Agronomy, Shanxi Agricultural University, Taigu 030801, China;College of Life Science and Geography, Qinghai Normal University, Xining 810008, China;Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050022, China)

机构地区：[1]中国科学院西双版纳热带植物园,昆明650223 [2]中国科学院大学,北京100049 [3]山西农业大学农学院,太谷030801 [4]青海师范大学生命与地理科学学院,西宁810008 [5]中国科学院遗传与发育生物学研究所农业资源研究中心,石家庄050022

出　　处：《中国生态农业学报》2017年第9期1345-1350,共6页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(31272239;31170228);云南省中青年学术带头人后备人才项目(2014HB043)资助~~

摘　　要：中亚滨藜是一种典型的盐生植物,广泛分布在我国盐碱地区。前期研究中,我们发现盐胁迫显著诱导了中亚滨藜幼苗根尖类黄酮的累积,但其中的生理机理尚不完全清楚。在不同盐浓度(50 mmol·L^(-1)、100 mmol·L^(-1)、250mmol·L^(-1)、500 mmol·L^(-1)、600 mmol·L^(-1) NaCl)处理下,通过添加KNO_3(25 mmol·L^(-1)、35 mmol·L^(-1))和外源槲皮素(100 nmol·L-1 quercetin),采用植物生理学和生物化学等研究方法,分析了盐诱导的类黄酮累积在调节中亚滨藜幼苗耐盐性中的生理机理。研究结果表明,使用外源类黄酮类物质——槲皮素进行处理,一方面更加抑制了盐胁迫下幼苗主根的生长,同时还显著降低了根部H_2O_2的累积和幼苗在盐胁迫下的MDA水平,但使可溶性糖含量显著升高。这些结果表明,槲皮素通过抑制主根生长,影响了中亚滨藜根系结构;通过降低氧化伤害,提高了中亚滨藜幼苗对盐胁迫的耐受性。盐胁迫还显著诱导了中亚滨藜幼苗对硝酸盐(NO3-)的累积,使用25mmol·L^(-1)和35 mmol·L^(-1) KNO3处理,可显著诱导其幼苗根尖类黄酮的累积。这些结果表明,硝态氮可能通过影响类黄酮途径,从而参与调控了中亚滨藜幼苗的耐盐性。本研究为进一步揭示中亚滨藜耐盐的生理与分子机制,以及类黄酮参与调控中亚滨藜耐盐性的生理与分子机理提供了理论基础;同时为使用现代生物技术和农艺措施提高作物耐盐性、改良盐碱地提供了理论依据和技术支持。Atriplex centralasiatica is a typical halophyte that widely grows in saline areas of China.In earlier studies,we found that salt stress markedly induced the accumulation of flavonoid in the roots of A.centralasiatica seedlings.By integrating the physiological and biochemical analyses in this study,the physiological mechanisms of salt-induced flavonoid accumulation in the roots of A.centralasiatica seedlings were investigated by supplementing with KNO3(25and35mmol·L?1)and exogenous quercetin(100nmol·L?1quercetin)in different salinity-treated seedlings(50,100,250,500and600mmol·L?1NaCl).Our results indicated that supplementation of exogenous quercetin markedly suppressed primary root(PR)growth and the accumulation of both H2O2and MDA in roots,whereas it markedly increased soluble sugar levels in seedlings.This indicated that exogenous flavonoid-quercetin affected root system architecture by suppressing PR growth and improved salt tolerance by reducing oxidative damage in A.centralasiatica seedlings.Salt stress also induced the accumulation of nitrate(NO3)in A.centralasiatica seedlings.We found that treatment with25and35mmol·L?1KNO3markedly induced the accumulation of flavonoid in root tips of A.centralasiatica seedlings.All in all,the results indicated that nitrate modulated salt tolerance inA.centralasiatica seedlings by flavonoid pathway.This knowledge was helpful for further elucidating the physiological and molecular mechanisms of salt tolerance in A.centralasiatica.It also provided further insights into novel strategies for breeding and cultivating salt-tolerant crops and improved saline-alkali soils using modern biotechnology and agricultural measure.

关 键 词：中亚滨藜 盐胁迫 类黄酮 硝酸盐 根系 

分 类 号：X592[环境科学与工程—环境工程]