干旱胁迫对油松和柴松钾钙离子流的影响  

Effect of drought stress on potassium and calcium fluxes in Pinustabulaeformisand Pinus tabulaeformis f.shekanensis

作　　者：王树源 王富[1] 唐佳琪 鲁彦君[1] 

机构地区：[1]西北农林科技大学林学院,陕西杨凌712100

出　　处：《西北农林科技大学学报（自然科学版）》2018年第1期21-29,共9页Journal of Northwest A&F University(Natural Science Edition)

基　　金：中央高校基本科研业务费项目(2452015044);西北农林科技大学博士科研启动基金资助项目(2013BSJJ049);"十二五"农村领域国家科技支撑计划项目(2015BAD07B0203)

摘　　要：【目的】比较干旱胁迫下,油松与柴松幼苗根、叶对K^+、Ca^(2+)的积累规律及其根尖表皮细胞对K^+、Ca^(2+)的跨膜转运模式,从K^+、Ca^(2+)平衡的角度揭示2种松树幼苗对干旱胁迫的响应差异。【方法】以培育5个月的油松和柴松幼苗为试验材料,对其分别进行短期(连续7d不浇水)和长期(连续21d不浇水)干旱胁迫处理,以每周浇2次水的幼苗为对照,于干旱胁迫结束时采用原子吸收法测定2种松树根、叶中K^+、Ca^(2+)含量,采用非损伤微测技术检测根尖离子流速;同时在干旱胁迫结束后,对油松和柴松根尖分别采用500μmol/L质膜H^+-ATP酶抑制剂原钒酸钠(sodium orthovanadate,Vanadate)预处理50min、采用20mmol/L质膜K^+通道抑制剂氯化四乙胺(tetraethylammonium,TEA)预处理30min、采用1mmol/L质膜Ca^(2+)通道抑制剂三氯化钆(Gadolinium chloride,GdCl3)预处理1h、采用5μmol/L质膜Ca^(2+)-ATP酶抑制剂Eosin yellow(Eosin-Y)预处理1h,然后检测根尖K^+流与Ca^(2+)流。【结果】与对照相比,短期干旱胁迫对2种松树根、叶组织中K^+、Ca^(2+)含量影响不显著,但长期干旱胁迫下2种松树根、叶组织中K^+、Ca^(2+)含量显著减少,其中油松对K^+、Ca^(2+)的积累大于柴松。短期干旱胁迫诱导油松根尖K^+从对照的轻微外排转为内流,长期干旱胁迫则增强K^+外排流速;与对照相比,柴松在短期与长期干旱胁迫下K^+外排均加强;对照条件下油松Ca^(2+)内、外流基本平衡,短期胁迫下Ca^(2+)内流加强,长期胁迫下在根尖伸长区Ca^(2+)外排加强;柴松在短期与长期干旱胁迫下较对照不同程度地加强了Ca^(2+)外排;油松根尖表皮细胞的K^+和Ca^(2+)内流速度均大于柴松。TEA显著抑制2种松树K^+外流,但Vanadate显著促进2种松树K^+外流,且其对柴松的影响没有油松显著;Eosin-Y可有效抑制2种松树Ca^(2+)外排,但GdCl3仅显著抑制油松Ca^(2+)内流,对柴松Ca^(2+)外流无效。【结论】油松【Objective】The K~＋ and Ca2＋ accumulation in roots and leaves and their transportation across plasma membrane of root tip epidermal cells of Pinus tabulaeformis and Pinus tabulaeformis f.shekanensis seedlings under drought stress were comparatively investigated,which would clarify the physiological differences between the two species in K~＋ and Ca2＋ homeostasis perspective.【Method】Using the seedlings of the two species watered twice per week as control,five-month seedlings were treated with shortterm（no watering for 7 d）and long-term（no watering for 21 d）drought stresses.K~＋ and Ca2＋ contents inroot and leaf were measured by Atomic Absorption Spectrometry and K~＋ and Ca2＋ fluxes from root tip were tested by Non-invasive Micro-measurement Technique at the end of drought stress.Besides,the root tips were pretreated with 500μmol/L sodium orthovanadate（Vanadate）as inhibitor of PM H＋-ATPase for 50 min,20 mmol/L tetraethylammonium（TEA）as inhibitor of K~＋ channel for 30 min,1 mmol/L Gadolinium chloride（GdCl3）as blocker of PM Ca2＋ channel and 5μmol/L Eosin yellow（Eosin-Y）as blocker of PM Ca2＋ -ATPase for 1 hour before testing K~＋ and Ca2＋ fluxes.【Result】Compared with the control,the short-term drought stress had no effect on K~＋ and Ca2＋ contentsin root and leaf of the two species,while the long-term stress induced the decrease of K~＋ and Ca2＋ contents significantly with more K~＋ and Ca2＋ accumulation in P.tabulaeformis.The short-term drought stress changed K~＋ in fluxes of P.tabulaeformis from slight K~＋ efflux under control,while the long-term stress enhanced K~＋ effluxes.Compared with the control,the K~＋ effluxes of P.tabulaeformis f.shekanensis were enhanced under both short-term and longterm stresses.Ca2＋ fluxes of P.tabulaeformis were in balance under control,it increased under short-term stress and only increased in apical elongation zone under long-term stress.Ca2＋ effluxes of P.tabulaeformis f.shekanensis were strenghthened

关 键 词：油松 柴松 干旱胁迫 K+流 Ca2+流 

分 类 号：S791.254.01[农业科学—林木遗传育种]