硝普纳处理对白刺愈伤组织膜脂过氧化及抗氧化酶活性的影响

以唐古特白刺（Nitraria tangutorum Bobr.）愈伤组织为材料,研究一氧化氮(NO)供体硝普钠（SNP）处理对其膜脂过氧化及抗氧化酶活性的影响。激光共聚焦扫描显微镜技术检测结果显示,白刺愈伤组织在SNP处理下细胞中NO含量显著增加,而N-硝基-L-精氨酸（L-NNA）处理使细胞中NO水平降低。低浓度SNP（10和25 μmol·L^-1）处理后,白刺愈伤组织中丙二醛（MDA）含量显著减少,而高浓度SNP（100 μmol·L^-1）和L-NNA(0.5 mmol·L^-1)处理后MDA含量明显高于对照。与对照比,SNP处理诱导白刺愈伤组织可溶性蛋白含量升高,却使脯氨酸含量减少。白刺愈伤组织在不同浓度SNP处理下过氧化氢酶（CAT）和抗坏血酸过氧化物酶（APX）活性呈增加的变化趋势,低浓度SNP处理使过氧化物酶（POD）活性减弱,而50 μmol·L^-1 SNP处理后POD活性约增加为对照的119%。结果提示,外源NO可促进白刺愈伤组织可溶性蛋白的合成,诱导抗氧化酶活性升高,增强了白刺愈伤组织的抗氧化能力,从而表现出对细胞的保护作用。     

外源脯氨酸（Pro）对茶菱抗Cd2+胁迫能力的影响

以高等水生植物茶菱（Trapella sinensis Olive）为材料,研究了外施不同浓度的脯氨酸（Pro）对Cd²⁺毒害的缓解效应。结果表明,茶菱体内Pro含量在单一Cd²⁺毒害下明显增加,外施Pro后,显著降低;叶绿素和可溶性蛋白含量在单一Cd²⁺毒害下大幅下降,外施Pro后,失绿症状有所减轻;保护酶（SOD、CAT、POD）系统在单一Cd²⁺毒害下比例失调,平衡被打破,活性下降,外施Pro后,SOD、POD活性较对照升高,CAT持平,其比例维持在正常范围内;O^－₂产生速率在单一Cd²⁺毒害下大大加快,外施Pro后,其产生速率恢复正常水平;丙二醛（MDA）含量在单一Cd²⁺毒害下积累加剧,外施Pro后,积累程度有所降低。因此,外源Pro可以通过减轻叶绿素和可溶性蛋白的降解,促进蛋白合成,减缓MDA积累,降低O^－₂产生速率,增强保护酶活性来增强植物对重金属胁迫的抗性,增强植物对逆境的适应能力。本实验中Pro作用的最佳浓度范围为40~60 mg·L^-1。     

外源NO对盐胁迫下黑麦草幼苗根生长抑制和氧化损伤的缓解效应

研究了外源一氧化氮(nitric oxide, NO)对盐胁迫下黑麦草幼苗根生长和氧化损伤的影响。结果表明,5~100 μmol·L^-1的NO供体硝普钠(sodium nitroprusside, SNP)处理显著减轻100mmol·L^-1 NaCl胁迫对黑麦草幼苗根生长的抑制效应,其中50 μmol·L^-1的SNP效果最明显,150 μmol·L^-1以上的SNP处理则抑制根的生长。50 μmol·L^-1 SNP处理提高了100 mmol·L^-1 NaCl胁迫下黑麦草幼苗根组织中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)及液泡膜上H⁺-ATP酶(H⁺-ATPase)和H⁺焦磷酸酶(H⁺-PPase)的活性,使谷胱甘肽(GSH)、抗坏血酸(ASA)和脯氨酸含量及K⁺/Na⁺、(Spd+Spm)/Put比值和根干物质积累量增加,超氧阴离子(O^-₂)、H₂O₂和丙二醛(MDA)含量降低,而1mmol·L^-1NO清除剂PTIO和1 μmol·L^-1 NaNO₂处理(对照)的效果则不明显。由此推断,NO通过提高根组织的抗氧化和渗透调节能力,促进根系对K⁺的选择性吸收及Put向Spd和Spm的转化,降低Na⁺的吸收并加强在液泡中的区隔化缓解盐胁迫对黑麦草幼苗根生长的抑制和膜脂过氧化损伤。     

一氧化氮(NO)熏蒸蒜瓣对蒜苗叶片光合作用的影响

以白皮改良蒜为试验材料,用不同浓度的一氧化氮气体（0.1、0.5、1.0 μmol·L^-1）在无氧环境中对大蒜进行熏蒸。并使用TPS 1便携式光合仪结合Farquhar和Sharkey的理论测定或计算NO处理蒜苗的相关光合指标,同时测定核酮糖-1,5-二磷酸羧化/加氧酶(Rubisco)含量。发现与1.0 μmol·L^-1 NO气体处理相比,0.5 μmol·L^-1 NO处理的蒜苗叶片净光合速率（P_n）、气孔导度(G_s)提高、而胞间隙CO₂浓度（C_i）、气孔限制值(L_s)降低,说明0.5 μmol·L^-1 NO处理下蒜苗光合速率高于1.0 μmol·L^-1 NO的处理的主要是非气孔因素。而且0.5 μmol·L^-1 NO处理提高了蒜苗叶片表观量子效率(AQY)、表观羧化效率(CE)和光合能力(A_o)及Rubisco含量,说明外源NO处理提高了蒜苗叶片光合作用过程中光反应能力和碳同化过程中羧化酶羧化效率。与对照相比,1.0 μmol·L^-1 NO处理降低了蒜苗叶片净光合速率,同时气孔导度、胞间隙CO₂浓度、表观量子效率、Rubisco含量、羧化效率和光合能力均降低,而气孔限制值升高,说明1.0 μmol·L^-1 NO对蒜苗光合作用的抑制既有气孔因素,也有非气孔因素。而0.1 μmol·L^-1 NO处理各项指标与对照无显著性的差异。     

外源一氧化氮对铅胁迫下小麦种子萌发及幼苗生理特性的影响

利用室内水培实验,研究了外源一氧化氮（NO）供体硝普钠（SNP）对Pb²⁺处理下小麦（Triticum aestivum L.）种子萌发、幼苗生长及相关生理指标变化的影响。结果表明,Pb²⁺处理使小麦种子发芽势、发芽率、幼苗根长和茎长均显著降低,诱导叶绿素a、叶绿素b含量减少及叶绿素荧光参数F_v/F_m和F_v/F_o的比值减小,25 μmol·L^-1 SNP明显缓解Pb²⁺胁迫对种子萌发及幼苗生长的抑制作用,提高Pb²⁺胁迫下叶绿素a、叶绿素b含量及F_v/F_m和F_v/F_o的比值,而100 μmol·L^-1SNP无明显缓解作用。此外,25和100 μmol·L^-1SNP诱导Pb²⁺胁迫下小麦幼苗叶片过氧化氢酶（CAT）活性增强和可溶性蛋白含量增多,但100 μmol·L^-1SNP处理降低了过氧化物酶（POD）活性。结果说明,外源NO促进Pb²⁺胁迫下小麦种子萌发及幼苗生长,提高叶绿素和可溶性蛋白含量,诱导CAT活性升高,从而增强小麦对Pb²⁺胁迫的适应性。     

外源NO对盐胁迫下黑麦草幼苗活性氧代谢、多胺含量和光合作用的影响

采用溶液培养法研究了外源一氧化氮(nitric oxide,NO)供体硝普钠(sodium nitroprusside,SNP)对100 mmol·L^-1 NaCl胁迫下黑麦草幼苗生长、活性氧代谢、多胺含量和光合作用的影响。结果表明,50 μmol·L^-1 SNP显著提高盐胁迫下黑麦草幼苗叶片的超氧化物歧化酶(SOD)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)活性及谷胱甘肽(GSH)、精胺(Spm)、亚精胺(Spd)含量和(Spm+Spd)/Put比值,降低了腐胺(Put)、超氧阴离子(O^—·₂)、H₂O₂和丙二醛(MDA)含量,使幼苗叶片叶绿素和类胡萝卜素含量、净光合速率(P_n)和气孔导度(G_s)升高,胞间CO₂浓度(C_i)下降,相对生长量增加。叶绿素荧光动力学资料显示,SNP处理降低盐胁迫下黑麦草叶片的初始荧光(F₀),表明它对光合膜系统具有保护效应。SNP处理不仅提高了盐胁迫下叶片的最大荧光(F_m)、PSⅡ潜在光化学效率(F_v/F₀)和PSⅡ最大光化学效率(F_v/F_m),而且提高了PSⅡ实际光化学效率(Φ_PSⅡ)、光化学荧光猝灭系数(q_P)、表观光合电子传递速率(ETR)和光化学速率(PCR),降低了非光化学荧光猝灭系数(NPQ)和天线热耗散(D),而1 mmol·L^-1 NO清除剂PTIO和0.5 μmol·L^-1 NaNO₂处理(对照)则无此效应。由此表明,外源NO可能通过提高植株的抗氧化能力及光能的捕获与转换而增强盐胁迫下黑麦草叶片的光合能力,从而缓解盐胁迫对幼苗生长的抑制作用。     

外源NO对南方红豆杉幼苗光合色素及抗氧化酶的影响

以4年生南方红豆杉幼苗为实验材料,通过对南方红豆杉幼苗喷施不同浓度外源一氧化氮（NO）供体硝普钠溶液（0、0.01、0.1、0.5和1 mmol·L^-1SNP）,测定光合色素含量、抗氧化酶活性、丙二醛（MDA）含量和过氧化氢（H₂O₂）含量等生理指标,以探讨不同浓度外源NO对南方红豆杉叶片光合色素和抗氧化酶的影响。结果表明：喷施低浓度（0.01、0.1 mmol·L^-1）SNP可显著提高南方红豆杉叶片的叶绿素a、叶绿素b、类胡萝卜素和总叶绿素含量,增加叶绿素a/b的比值,而喷施高浓度（0.5、1 mmol·L^-1）SNP降低了叶片的光合色素含量。随着外源NO供体浓度的增加,叶片过氧化氢酶(CAT)活性显著增加,过氧化物酶(POD)活性先增加后降低。此外,处理前期,低浓度SNP处理明显提高了抗坏血酸过氧化物酶(APX)活性,而高浓度SNP处理显著降低了APX活性,处理后期APX活性随SNP浓度的增加而显著下降。喷施低浓度SNP可有效提高超氧化物歧化酶(SOD)活性和增加可溶性蛋白含量,降低MDA和H₂O₂的含量,而喷施高浓度SNP显著增加了MDA和H₂O₂的含量。因此,低浓度的SNP（<0.5 mmol·L^-1）处理南方红豆杉幼苗,可增加其叶绿素含量,提高抗氧化酶活性,降低MDA和H₂O₂的含量,而高浓度的SNP（≥0.5 mmol·L^-1）处理会降低叶绿素含量,提高H₂O₂含量,增加细胞膜质过氧化程度,从而对南方红豆杉幼苗造成一定伤害。     

外源一氧化氮对NaCl胁迫下黄瓜幼苗生长、活性氧代谢和光合特性的影响

采用营养液水培的方法,研究了外源一氧化氮（Nitric oxide, NO）对50mmol•L^-1NaCl胁迫下黄瓜幼苗生长、活性氧代谢和光合特性的影响。结果表明：10~400μmol•L^-1 NO供体硝普钠（Sodium nitroprusside, SNP）能显著缓解NaCl胁迫对黄瓜植株造成的伤害,100μmol•L^-1 SNP缓解效果最好,可提高幼苗的生长量,增强幼苗叶片超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）、抗坏血酸过氧化物酶（APX）活性,提高了叶片叶绿素和脯氨酸（Pro）含量、净光合速率（Pn）、蒸腾速率（Tr）及气孔导度（Gs）;降低了叶片丙二醛（MDA）和过氧化氢（H₂O₂）的含量、超氧阴离子（O^•-₂）的产生速率、质膜透性和胞间二氧化碳浓度（Ci）。     

Na2CO3胁迫下星星草幼苗活性氧及保护酶活性的变化

对低浓度Na₂CO₃胁迫下星星草幼苗相对电导率、O^-₂产生速率、H₂O₂含量以及保护酶CAT、SOD和POD活性的研究结果表明,低盐胁迫1 d后,星星草幼苗细胞膜的通透性、O^-₂产生速率、H₂O₂含量及保护酶活性都随着盐胁迫的加剧而升高,其具体的变化规律与盐胁迫强度和幼苗细胞膜的受损伤程度密切相关,但相关关系的性质上具有差异。     

机械伤害和外源茉莉酸诱导豌豆幼苗H2O2系统性产生

以豌豆(Pisum sativum L.)幼苗为试材, 采用DAB组织染色、CeCl₃细胞化学染色和TiCl₄显色等多种方法, 跟踪了伤害和外源茉莉酸(jasmonic acid, JA)处理后H₂O₂的时空动态变化. 结果显示, 伤害和外施JA可以诱导H₂O₂系统性产生, 无论是伤害叶片、邻近未伤害叶片还是低节位远端叶片, 伤害处理后1 h, H₂O₂含量即有所增加, 3~5 h后H₂O₂含量达到最大, 随后开始下降, 至处理后12 h, H₂O₂含量基本恢复到对照水平; 相应地, 伤害和JA处理后, 抗氧化酶类活性迅速提高; NADPH氧化酶抑制剂二苯基碘(diphenylene iodonium, DPI)可以显著抑制伤害和JA诱导的H₂O₂迸发. H₂O₂亚细胞定位结果显示, 伤害和JA诱导产生的H₂O₂主要分布于质膜、细胞壁和细胞间隙. JA的胶体金免疫电子显微镜定位结果表明, 伤害后JA含量迅速增加, 显示在叶肉细胞的细胞壁和韧皮部筛管与伴胞分子中金颗粒数量明显增加.     

Exogenous H2O2 increased catalase and peroxidase activities and proline content in Nitraria tangutorum callus

Antioxidative responses and proline accumulation induced by exogenous H₂O₂ were investigated in the callus from halophyte Nitraria tangutorum Bobr. H₂O₂-treated callus exhibited higher H₂O₂ content than untreated callus. The activities of catalase (CAT) and peroxidase (POD) significantly increased in the callus treated with H₂O₂, while ascorbate peroxidase (APX) activity decreased. In addition, significantly enhanced proline content was observed in the callus treated by H₂O₂, which could be alleviated by H₂O₂ scavenger dimethylthiourea and calcium (Ca) chelator ethylene glycol bis-(β-aminoethyl ether)-N,N,N′,N′-tetra-acetic acid (EGTA). Moreover, γ-glutamyl kinase (GK) activity increased in H₂O₂-treated callus, but proline dehydrogenase (PDH) activity decreased significantly, and the reduction was partly abolished by EGTA or Ca channel blocker verapamil. Assays using a scanning electron microscope showed significantly enhanced Ca content in H₂O₂-treated callus.     

ROS generation and proline metabolism in calli of halophyte Nitraria tangutorum Bobr. to sodium nitroprusside treatment

Nitric oxide (NO) is a stress factor or a signal molecule involved in various plant physiological and developmental processes. In the present study, the generation of reactive oxygen species and the metabolism of proline due to different sodium nitroprusside (SNP, an NO donor) concentrations were investigated in callus from halophyte Nitraria tangutorum Bobr. Treatment with SNP led to significant increases of hydrogen peroxide (H₂O₂) content and cell viability but notable reductions in hydrogen radical level and lipid peroxidation degree, and superoxide onion (O₂ ^?) content also enhanced in 100 μM SNP-treated calli. Using a chemical inhibitor for plasma membrane (PM) NADPH oxidase diphenylene iodonium (DPI), we found low O₂ ^? generation in untreated and 25 μM SNP-treated calli, whereas in those treated with 100 μM SNP O₂ ^? level exhibited a very little alteration, comparable to the absence of DPI. These suggest a high activity of PM NADPH oxidase in untreated calli. H₂O₂ scavenging enzymes (catalase, peroxidase [POD] and ascorbate peroxidase) and H₂O₂ forming enzymes (superoxide dismutase [SOD], cell wall-POD and diamine oxidase [DAO]) stimulated significantly in calli treated with different SNP concentrations while glutathione reductase activity decreased. In addition, a reduction in proline content was observed in SNP-treated calli. Moreover, different SNP concentrations stimulated proline dehydrogenase (PDH) and ornithine δ-aminotransferase but inhibited r-glutamyl kinase (GK). In conclusion, our results suggest that the increasing H₂O₂ generation was associated with the stimulation of SOD, cell wall-POD and DAO, and that the reduction of proline content might be the consequence of increased PDH activity and decreased GK activity in N. tangutorum Bobr. calli under SNP treatment.     

Signal regulation of proline metabolism in callus of the halophyte Nitraria tangutorum Bobr. grown under salinity stress

Callus of the halophyte Nitraria tangutorum Bobr. was used to investigate proline metabolism and its signal regulation under salinity stress. Enhanced levels of proline and hydrogen peroxide (H₂O₂) were observed in calli exposed to salinity stress, and elevated levels of calcium (Ca) were detected in early responses to 75?mM NaCl treatment. Additionally, NaCl treatment induced significant elevation of ornithine-??-aminotransferase (OAT) activity, but notable decreases occurred in the activities of glutamyl kinase (GK) and proline dehydrogenase (PDH). H₂O₂ scavenger dimethylthiourea and pyruvate inhibited the accumulation of proline and the stimulation of OAT in salinity-stressed calli. Moreover, the utilization of Ca chelator EGTA and Ca channel blocker verapamil abolished the enhancement of proline level induced by 75?mM NaCl treatment for 3?days. These results suggest that the accumulation of proline is correlated to the increase of OAT activity and the decrease of PDH activity in response to salinity, and that elevated Ca signal during the early stage of NaCl treatment and the excitation of OAT activity resulting from the increase of H₂O₂ generation are essential for proline accumulation in salinity-stressed calli.     

Effect of salinity on antioxidant enzymes in calli of the halophyte <Emphasis Type="Italic">Nitraria tangutorum</Emphasis> Bobr.

Nitraria tangutorum Bobr., a typical desert halophyte, plays an important ecological role because of its superior tolerance to severe drought and high salinity. Very little is known about the physiological adaptative mechanism of this species to environmental stresses. The aim of this study was to investigate the changes of antioxidant enzyme activities and the regulatory mechanism of ascorbate peroxidase (APX) activity in the calli from Nitraria tangutorum Bobr. after treatment with different NaCl concentrations. The activities of superoxide dismutase (SOD) and catalase (CAT) significantly increased in the calli treated with NaCl, while the peroxidase activity decreased. APX activity was also elevated significantly in response to NaCl, but the increase was partly abolished by H₂O₂ scavenger dimethylthiourea (DMTU). Furthermore, the excitatory effect of salinity on APX could be alleviated by the addition of exogenous CAT and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor diphenylene iodonium, indicating that the modulation of the APX activity in Nitraria tangutorum Bobr. calli might be associated with NADPH oxidase-dependent H₂O₂ generation. Measurement and analysis using fluorescent dye 2′,7′-dichlorodihydrofluorescein diacetate showed the increase of H₂O₂ content in salinity-treated calli. The investigation of NADPH-dependent O₂⁻ production in plasma membrane (PM) vesicles isolated from Nitraria tangutorum Bobr. calli revealed that salinity treatment stimulated NADPH oxidase activity. In conclusion, these results suggest that the higher activities of antioxidant enzymes play an important role in the salt tolerance of Nitraria tangutorum Bobr. calli and that the extracellular production of H₂O₂, depending on the excitation of PM NADPH oxidase, is responsible for enhancing the APX activity in Nitraria tangutorum Bobr. calli under salinity stress.     

孝顺竹愈伤组织增殖培养基优化研究

为筛选适宜孝顺竹愈伤组织继代增殖培养基,控制褐变发生,提高再生体系效率,对培养基组成如5种基本培养基、6种有机添加物、7种糖类和5种大量元素等因子进行试验分析。结果表明：培养20 d,基本培养基以MS效果较好,愈伤组织增殖2.8倍,白至淡黄色,致密;有机添加物以1.0 g·L^-1脯氨酸效果较显著,愈伤组织增殖3.64倍,淡黄色,致密均一;碳源以30 g·L^-1麦芽糖效果较好,愈伤组织增殖2.96倍,白至淡黄色,致密。5种大量元素中NH₄NO₃对孝顺竹愈伤组织增殖的影响达到显著水平,以825 mg·L^-1为较佳浓度,培养29 d愈伤组织增殖可达5倍以上,部分出现根分化;适宜孝顺竹愈伤组织培养的大量元素组合为：KNO₃ 475 mg·L^-1+NH₄NO₃ 825 mg·L^-1+MgSO₄·7H₂O 185 mg·L^-1+KH₂PO₄ 340 mg·L^-1+CaCl₂·7H₂O 440 mg·L^-1。     

硝普钠缓解镧引起的黑麦草幼苗生长抑制和根系氧化损伤

采用水培方法,研究了外源一氧化氮（NO）供体硝普钠（SNP）对300 μmol·L^-1 LaCl₃胁迫下黑麦草幼苗生长和根系活性氧代谢的影响。结果表明：在LaCl₃胁迫下,喷施50 μmol·L^-1 SNP能够抑制镧（La）从黑麦草根系向地上部的转运,缓解La对幼苗生长的抑制作用;提高幼苗根系超氧化物歧化酶和抗坏血酸过氧化物酶活性,降低过氧化物酶活性及谷胱甘肽、脯氨酸、H₂O₂、丙二醛含量、超氧阴离子产生速率和质膜相对透性,对过氧化氢酶活性和抗坏血酸含量无显著影响。表明NO可通过活性氧代谢的调节,缓解高浓度La胁迫对黑麦草幼苗生长的抑制作用。     

Salinity-induced Physiological Modification in the Callus from Halophyte Nitraria tangutorum Bobr.

Little is known about the physiological adaptation mechanisms of the desert halophyte Nitraria tangutorum Bobr. to the environment. In this study, callus from Nitraria tangutorum Bobr. was used to investigate physiological responses to salinity and the regulatory function of nitric oxide (NO) on catalase (CAT) activity. Increased dry weight and soluble proteins were observed in the callus exposed to lower salinity (50 and 100 mM NaCl), whereas 200 mM NaCl led to significant decreases of these two growth parameters, and the levels of proline and soluble carbohydrates also were enhanced under NaCl treatment. In addition, short-term stress from 50 mM NaCl and the application of lower sodium nitroprusside (SNP, a NO donor) concentration resulted in decreased levels of malondialdehyde (MDA). In contrast, higher concentrations of NaCl and SNP induced significant oxidative damage in Nitraria tangutorum Bobr. callus. Analysis based on the fluorescent probe DAF-FM DA revealed that NaCl and SNP treatment led to enhanced levels of NO in the callus cells. Moreover, the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO) reduced endogenous NO concentrations and abolished the enhancement in dry weight and the decrease in MDA level under 50-mM-NaCl treatment. CAT activity increased under salt stress, and the 50-mM-NaCl effect was alleviated by treatment with c-PTIO or the nitric oxide synthase inhibitor N^ω-nitro-l-arginine. We suggest that Nitraria tangutorum Bobr. callus exhibited tolerance to lower-salinity stress. We also showed that increased NO generation in response to salinity might be associated with regulation of growth, protection against oxidative damage, and excitation of CAT activity in Nitraria tangutorum Bobr. callus under salt stress.     

过量表达水稻细胞质型OsAPXs基因提高转基因烟草的耐盐性

为了验证水稻(Oryza sativa L.)细胞质型APXs与细胞耐盐性的关系,实验分别将OsAPXa和OsAPXb（基因登录号：D45423、AB053297）转化到烟草(Nictiana tabacum,N.plum)植株中。Southern结果表明,二基因分别整合到烟草的基因组;Northern分析表明,外源基因在转基因烟草中得到高效表达;在碳酸盐逆境下,T2代转基因植株与野生型对照相比,其APX活性呈现显著的提高,T₂代品系的H₂O₂含量和叶片受害程度显著低于野生型;T₂代品系分别在含有10 mmol·L^-1 NaHCO₃、5 mmol·L^-1 Na₂CO₃的MS培养基上生长,根的生长受到抑制,叶片产生黄化;野生型烟草则难以存活。水稻细胞质型OsAPXs基因的过量表达提高了转基因烟草的耐盐性,揭示出OsAPXa和OsAPXb在碳酸盐逆境应答过程中发挥着重要的作用。     

NaCl处理下黄花补血草幼苗生理特性的变化

以荒漠盐生植物黄花补血草(Limonium aureum(Linn.) Hill)为材料,研究不同浓度NaCl处理下渗透调节物含量、活性氧产生和抗氧化酶活性的变化。结果显示：NaCl处理诱导黄花补血草幼苗脯氨酸、可溶性糖和H2O2含量升高及超氧阴离子（O₂^-·）产生速率增大,可溶性蛋白含量在25和50 mmol·L^-1 NaCl处理时低于对照,而100和150 mmol·L^-1 NaCl处理时显著增加;不同浓度NaCl处理下,黄花补血草超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)活性显著升高,过氧化物酶活性与对照比呈现先增加后减小的变化,而过氧化氢酶活性表现为先降低后升高的变化趋势,但均低于对照。结果表明,黄花补血草在盐胁迫下通过积累渗透调节物和提高SOD、APX活性,使其具有较强的渗透调节能力和抗氧化能力,从而增强对盐环境的适应性。