向日葵芽苗期离子对复合盐胁迫的响应  

Ion response of sunflower at sprouting stage to mixed salt stress

作　　者：马荣[1,2] 王成[3,4] 马庆[2] 侯佩臣[3] 王晓冬[1,4] MA Rong;WANG Cheng;MA Qing;HOU Peichen;WANG Xiaodong(Beijing Research Center of Intelligent Equipment for Agriculture, Beijing 100097, China;Beijing Research Center for Information Technology in Agriculture, Beijing 100097, China;College of Agriculture, Inner Mongolia Agricultural University, Hohhot 010019, China;Beijing Key Lab of Digital Plant, Beijing Research Center for Information Technology in Agriculture,Beijing 100097, China)

机构地区：[1]北京农业智能装备技术研究中心,北京100097 [2]内蒙古农业大学农学院,呼和浩特010019 [3]北京农业信息技术研究中心,北京100097 [4]数字植物北京重点实验室,北京100097

出　　处：《中国生态农业学报》2017年第5期720-729,共10页Chinese Journal of Eco-Agriculture

基　　金：国家重大科学仪器设备开发专项(2011YQ080052);北京市农林科学院数字植物科技创新团队(JNKYT201604);国家自然科学基金项目(61571443)资助~~

摘　　要：研究向日葵耐盐的离子响应机制,可为快速筛选耐盐向日葵品种提供科学依据。本试验以油用向日葵盐敏感品种‘YK18’、中度耐盐品种‘YK06’和耐盐品种‘GF01’为试验材料,研究0 mmol·L^(–1)、50 mmol·L^(–1)、100 mmol·L^(–1)、150 mmol·L^(–1)、200 mmol·L^(–1)和250 mmol·L^(–1)复合盐(NaCl和Na_2SO_4按9∶1摩尔比混合)浓度下的种子萌发和离子在萌发幼苗中积累分布情况,并利用离子流检测技术,动态监测了复合盐胁迫24 h后植株根系的K^+、Na^+、Ca^(2+)等离子的流速流向。结果表明,复合盐胁迫抑制向日葵种子萌发,导致发芽率下降,平均发芽时间延长。盐胁迫后向日葵根系K^+大量外排,流速为‘YK18’>‘YK06’>‘GF01’;随着盐胁迫浓度升高,根系Na^+流速由内吸转为外排,内吸时‘YK18’速度最大,‘YK06’次之,‘GF01’最小,外排时‘GF01’流速最大,其"排盐"现象明显。复合盐胁迫后,整株的Na^+积累量增加,K^+减少,K^+/Na^+随着盐浓度升高而下降;低盐浓度(<150 mmol·L^(–1))下‘GF01’和‘YK06’茎秆中K^+/Na^+低于‘YK18’;高盐胁迫(≥150 mmol·L^(–1))下,‘GF01’整株Na^+积累最少,叶片K^+/Na^+最高。另外,盐胁迫下向日葵幼苗根系Ca^(2+)的吸收速率加快,‘GF01’是‘YK18’的2倍。由此可见,不同耐盐性的油用向日葵植株在盐胁迫下可通过调节Na^+、K^+和Ca^(2+)的吸收与外排来适应盐胁迫环境,耐盐性强的品种具有更强的保K^+能力,并通过区域化Na^+(低盐胁迫)和拒盐机制(高盐胁迫)来提高其对盐胁迫的耐受性,维持植株叶片中合理的K^+/Na^+值。本研究结果可为盐碱地耐盐品种筛选和栽培提供理论依据。Research on the mechanism of response of sunflower to salt stress can provide scientific basis for rapid screening of salt resistant varieties,a critical element in the exploitation of saline-alkali lands.In this study,salt-sensitive variety'YK18',moderately salt-tolerant variety'YK06'and highly salt-tolerant variety'GF01'of sunflower were used to analyze seed germination,ion accumulation and distribution in seedlings of different varieties of sunflower under mixed salt(NaCl/Na2SO4of9/1mol)concentrations of0mmol·L-1,50mmol·L-1,100mmol·L-1,150mmol·L-1,200mmol·L-1and250mmol·L-1.Scanning ion-selective electrode technique SIET)was used to determine K+,Na+and Ca2+fluxes in roots after24h mixed salt stress.The results showed that seed germination,germination rate and germination index decreased under salt tress and the average germination time of oil sunflower extended.Under alt-stress condition,there was an obvious K+efflux in roots.Compared with high salt-tolerant variety'GF01',the roots of salt-sensitive ariety'YK18'and moderate salt-tolerant variety'YK06'had higher K+extrude capacity.Salt stress led to a net Na+influx in the range f0-100mmol·L-1in mixed salt concentrations,and was highest for salt-sensitive variety'YK18'.The pattern of Na+flux in rootschanged significantly under higher mixed salt concentrations(150-200mmol·L-1)and there was a clear efflux of Na+in seedlings,which as highest for salt-tolerant variety'GF01'.After mixed salt stress,Na+content increased while K+content decreased,resulting in a decrease in K+/Na+ratio in the whole plant.Salt-tolerant variety'GF01'had the lowest K+/Na+ratio,had the potential to intercept Na+in stems under low salt concentration(<150mmol·L-1).The sunflower variety'GF01'had higher capacity to extrude Na+.As a result,GF01'had the least Na+content(for the whole plant)and had higher K+/Na+ratio in leaves under high salt stress(≥150mmol·L-1).SIET data also showed that after24h exposure to mixed salt stress,a clear Ca2+influx in salt stressed seedlings that was prop

关 键 词：向日葵 芽苗期 复合盐胁迫 离子流 耐盐性 

分 类 号：S565.5[农业科学—作物学]