Effects of Calcium on Absorption and Distribution of Ions and H+-ATPase Activity in Barley and Wheat Under Salt Stress

Calcium decreased Na+ absorption and transportation to the shoots,increased K+ and Ca2+ absorption and transportation ,decreased the leakage of electrolyties,and increased the accumulation of dry matter in barley and wheat seedlings under NaC1 stress. Calcium ion promoted the H+-ATPase activities in plasma membrane and tonoplast vesicles isolated from the young roots of the two plants, and increased respiration of the roots. This is in consistent with the results that calcium regulates ion absorption and distribution via its enhancement of H+-ATPase activities in plasma membrane and tonoplast.     

一氧化氮调节盐胁迫下小麦幼苗根部质膜H^＋-ATPase和焦磷酸酶活性提高耐盐性

采用外源一氧化氮(NO)供体硝普钠(SNP)研究了NO对盐胁迫下小麦(Triticum aestivum L.)幼苗耐盐性的影响。结果表明,0.1 mmol/L SNP处理显著缓解了150 mmol/L NaCl 胁迫对小麦幼苗生长的抑制效应,包括水分丧失以及叶绿素降解,从而提高了小麦幼苗的耐盐性。进一步结合1 mg/mL血红蛋白处理则显著逆转了SNP诱导的上述效应;利用亚硝酸钠和铁氰化钾作为对照也证实了NO对小麦幼苗耐盐性的专一性调节作用,并可能与NO对小麦幼苗根部质膜 H -ATPase和焦磷酸酶活性诱导有关。此外,尽管NO显著提高了盐胁迫下小麦幼苗根部细胞质膜H -ATPase和焦磷酸酶的ATP水解活性,但是对跨膜H 转运则没有明显影响。应用外源CaSO4 和 EGTA 处理也证实,Ca2 可能在NO诱导的质膜 H -ATPase和焦磷酸酶活性的提高过程中起信号作用。另外,分析盐胁迫下小麦幼苗根部 Na 和K 含量的变化也发现,NO对Na 含量没有明显影响,但是却显著提高了K 水平和K /Na 比,这可能也是NO提高小麦幼苗耐盐性的原因之一。     

Effects of sodium chloride stress and calcium supply on growth, potassium uptake, and internal chloride and sodium levels of winter wheat seedlings

The effects of saline conditions on the K+ (86Rb), Na+ and Cl- uptake and growth of 6-day-old wheat (Triticum aestivum L. cv. GK Szeged) seedlings were studied in the absence and presence of Ca2+. It was found that on direct NaCl treatment the K+ uptake of the roots in the absence of Ca2+ declined significantly with increasing salinity. The reverse was true, however, in the case of NaCl pretreatment: seedlings grown under highly saline conditions (50 mM NaCl) absorbed more K+ than those pretreated with low levels of NaCl (1 or 10 mM NaCl). The data indicate a definite Na(+)-induced K+ uptake inhibition and/or feed-back regulation in the K+ uptake of roots under the above-mentioned growth conditions. As regards the Ca2+ effect, it was established that supplemental Ca2+ counteracts the unfavourable effect of saline conditions as concerns both the K+ uptake of the roots and the dry matter yield of the seedlings. The internal concentrations of Na+ and Cl- in the seedlings increased in proportion to increasing salinity. Marked differences were experienced, however, in the internal concentrations of Na+ and Cl- in the roots and shoots, respectively. It was concluded that under these experimental conditions the salt tolerance of wheat could be related to its capability of restricting the transport of Na+ at low and moderate levels to the shoots, where it is highly toxic.     

盐胁迫下构树幼苗各器官中K+、Ca2+、Na+和Cl-含量分布及吸收特征

将当年生构树幼苗置于含有不同浓度（04、1、2、3、4 g·kg^-1）NaCl的土壤中,研究其生物量积累、叶片细胞质膜透性和K⁺、Ca²⁺、Na⁺、Cl^-等离子的吸收、分布及运输,并观察盐害症状.结果表明：构树幼苗的叶片质膜透性随着NaCl浓度的增加和胁迫时间的延长而升高,根冠比随NaCl浓度的升高而增加,大于3 g·kg^-1的土壤盐胁迫对构树叶片的质膜透性及植株的生物量积累影响显著.构树幼苗各器官中Na⁺和Cl^-含量随土壤NaCl浓度升高而显著增加,K⁺和Ca²⁺则随之降低,叶片各离子含量均明显高于根和茎.说明盐胁迫影响根系对K⁺和Ca²⁺的吸收,并抑制了它们向地上部分的选择性运输,使叶和茎的K⁺和Ca²⁺含量下降.构树通过吸收积累Na⁺和Cl^-抵御土壤盐分带来的渗透胁迫,但过量的Na⁺和Cl^-积累会造成单盐毒害.作为抗盐性较高的非盐生植物,构树地上部分的拒盐作用不显著.     

盐胁迫下构树幼苗各器官中K+、Ca2+、Na+和Cl-含量分布及吸收特征

将当年生构树幼苗置于含有不同浓度（04、1、2、3、4 g·kg^-1）NaCl的土壤中,研究其生物量积累、叶片细胞质膜透性和K⁺、Ca²⁺、Na⁺、Cl^-等离子的吸收、分布及运输,并观察盐害症状.结果表明：构树幼苗的叶片质膜透性随着NaCl浓度的增加和胁迫时间的延长而升高,根冠比随NaCl浓度的升高而增加,大于3 g·kg^-1的土壤盐胁迫对构树叶片的质膜透性及植株的生物量积累影响显著.构树幼苗各器官中Na⁺和Cl^-含量随土壤NaCl浓度升高而显著增加,K⁺和Ca²⁺则随之降低,叶片各离子含量均明显高于根和茎.说明盐胁迫影响根系对K⁺和Ca²⁺的吸收,并抑制了它们向地上部分的选择性运输,使叶和茎的K⁺和Ca²⁺含量下降.构树通过吸收积累Na⁺和Cl^-抵御土壤盐分带来的渗透胁迫,但过量的Na⁺和Cl^-积累会造成单盐毒害.作为抗盐性较高的非盐生植物,构树地上部分的拒盐作用不显著.     

NaCl、Na2 SO4 和Na2GO3 胁迫对小麦叶片自由基含量及质膜透性的比较研究

 分别用浓度为25mmol／L、50mmol／L、100 mmol／L和200 MMOL／l的Nacl、Na2SO4和Na2CO3的营养液培养小麦4d,较之不含盐的营养液,其自由基含量上升,产生速率增加,叶片质膜透性增加。不同盐的影响也不同,在低浓度时,NaCl的影响大于Na2SO4,高浓度时,NaCl影响小于Na2CO3,Na2CO3的影响最为显著。实验结果也表现出小麦叶片自由基含量和质膜透性呈现较好的相关性。因此可认为,盐胁迫促使自由基含量增加,自由基通过过氧化作用影响质膜透性,从而影响植物的生长。     

盐胁迫下不同的钙盐对小麦幼苗耐盐性的影响

利用Ca(N03)2和CaCl2可以提高生长在盐渍条件下小麦幼苗的耐盐能力,增加幼苗的干、鲜重。其原因是由于两种钙盐均能防止膜脂过氧化,降低质膜透性,减少细胞内营养物质外渗,阻止Na+进入细胞。实验结果证明,在降低小麦幼苗盐害方面,Ca(N03)2好于CaCl2。讨论了两个钙盐在降低盐害机理方面的差异。     

盐胁迫下柚和橘幼苗体内矿质元素变化的比较研究

采用沙培法,对盐胁迫下坪山柚和福橘幼苗体内矿质元素的变化进行了研究。结果表明,随着NaCl浓度的增加,坪山柚和福橘幼苗根部及地上部Na^＋、Cl-含量增加,且相同浓度下,福橘比坪山柚高。40mmol／L NaCI胁迫下,坪山柚和福橘幼苗地上部的K^＋、Fe含量,根部的Ca^2＋、Mg^2＋、Zn含量显著下降,而根部Fe含量及地上部Zn含量显著增加。随NaCl浓度增大,坪山柚根部K^＋含量,地上部Ca^2＋、Mg^2＋含量变化不明显,而福橘根部、地上部上述离子含量在NaCl浓度≥160mmol／L时均显著下降。因此,根部K^＋含量,地上部Ca^2＋、Mg^2＋含量存在品种问差异,或许可作为耐盐性鉴定指标。NaCl胁迫降低坪山柚和福橘幼苗根部及地上部P、Mn含量,而Cu含量在较高浓度NaCl胁迫下显著增加。NaCl胁迫明显降低坪山柚和福橘幼苗地上部K^＋／Na^＋、Ca^2＋／Na^＋和Mg^2＋／Na^＋值,其中K^＋／Na^＋值的变化可考虑作为柑橘耐盐性鉴定的指标。     

氯化钠胁迫对不同品种南瓜幼苗阳离子含量的影响

选择19个不同类型南瓜品种,研究了300 mmol·L^-1 NaCl胁迫条件下,幼苗地上部和根系Na⁺、K⁺、Ca²⁺含量、Na⁺/K⁺、Na⁺/Ca²⁺、钠-钾和钠-钙运输选择性系数(S_Na⁺,K⁺和S_Na⁺,Ca²⁺值)的变化.结果表明：NaCl胁迫处理8 d后,不同品种南瓜幼苗Na⁺含量均明显增加,而K⁺含量下降,离子平衡被打破.青栗（Q₁）南瓜幼苗根系Na⁺含量、地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值均明显高于黑蜜南瓜（H₂）和黑籽南瓜（H₃）.不同品种南瓜幼苗体内Na⁺含量、地上部Na⁺/K⁺和Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值变化趋势与NaCI胁迫下不同品种南瓜幼苗盐害指数的结果基本一致,进一步验证了Q₁耐盐性强与NaCl胁迫下地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值较低以及K⁺、Ca²⁺含量较高有关;而H₂和H₃对盐敏感与NaCl胁迫下地上部Na⁺/K⁺、Na⁺/Ca²⁺、S_Na⁺,K⁺和S_Na⁺,Ca²⁺值较高,以及K⁺、Ca²⁺含量较低有关.     

Total polar lipid biosynthesis during growth of Crotalaria juncea pollen tubes

[1-¹⁴C]-Acetate incorporation into total and polar lipids was studied in the growing pollen tubes of Crotalaria juncea. Ungerminated pollen had phosphatidyl inositol, phosphatidyl serine, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, monogalactosyl diglyceride, digalactosyl diglyceride, sulpholipid and steryl glycosides. In the growing pollen tubes considerable [1-¹⁴C]-acetate incorporation was observed into the individual polar lipids. The exogenous carbon source significantly influenced lipid biosynthesis. Boric acid (20mg/l.) promoted both pollen tube growth and acetate incorporation into phospholipids. In comparison to 5′-adenosine monophosphate, cyclic-3′,5′-adenosine monophosphate (cAMP) promoted tube growth and also enhanced phospho-and glycolipid biosynthesis. The regulation of membrane component biosynthesis by cAMP is suggested.     

The Effect of Salt and Water Stress on Membrane Lipid Peroxidation in leaf Cells of Halophyte and Non-halophyte

Different concentrations of NaC1 and isoosmotic polyethylene glycol(PEG)were used to treat the seedlings of halophyte Suaede salsa and non-halophyte Prosopis chilensis. Membrane lipid peroxidation malondialdehyde(MDA)content,SOD activity and plasmalemma permeability were determined at different time of treatment. The seedlings of Suaeda salsa showed no or a little response to 0--1. 488 MPa NaCl,but marked response to 1. 984 MPa NaC1. However,there was a greater response to isoosmotic PEG in plasmalemma permeability, SOD activity and MDA content. Prosopis chilensis showed an contrary trend to Suaeda salsa. The MDA content decreased unanimously as three kinds of free-radical scavengers were sprayed on the seedlings of the above plants before NaCl or PEG treatment, but increased with pretreatment of SOD inhibitor. Obviously, the decrease of SOD activity and the increase of MDA content were related to plasma injury, and free-radical did participate the course of salt and/or water stress injury. Their effects of both salt and water stress shared common features in response to the integrity of the cell membrane.     

一氧化氮调节盐胁迫下小麦幼苗根部质膜H+-ATPase和焦磷酸酶活性提高耐盐性

采用外源一氧化氮(NO)供体硝普钠(SNP)研究了NO对盐胁迫下小麦(Triticum aestivum L.)幼苗耐盐性的影响.结果表明,0.1 mmol/L SNP处理显著缓解了1 50 mmol/L NaCl胁迫对小麦幼苗生长的抑制效应,包括水分丧失以及叶绿素降解,从而提高了小麦幼苗的耐盐性.进一步结合1 mg/mL血红蛋白处理则显著逆转了SNP诱导的上述效应;利用亚硝酸钠和铁氰化钾作为对照也证实了NO对小麦幼苗耐盐性的专一性调节作用,并可能与NO对小麦幼苗根部质膜H -ATPase和焦磷酸酶活性诱导有关.此外,尽管NO显著提高了盐胁迫下小麦幼苗根部细胞质膜H -ATPase和焦磷酸酶的ATP水解活性,但是对跨膜H 转运则没有明显影响.应用外源CaSO4和EGTA处理也证实,Ca2 可能在NO诱导的质膜H -ATPase和焦磷酸酶活性的提高过程中起信号作用.另外,分析盐胁迫下小麦幼苗根部Na 和K 含量的变化也发现,NO对Na 含量没有明显影响,但是却显著提高了K 水平和K /Na 比,这可能也是NO提高小麦幼苗耐盐性的原因之一.     

Difference in Na+,K+ Accumulation in the Salt tolerant Mutant and the Wild Type of Wheat During Exposure to NaCl Stress

The difference in Na+, K+ accumulation between the mutant and the wild type of wheat ( Triticum aestivum L. ) has been investigated. The authors report here that the mutant accumulated less Na + in the root and leaf than the wild type in response to NaCI stress. This difference in Na + accumulation in leaf was more significant than that in the root. The mutant kept a lower net accumulation rate of Na + than that in the wild type during the stress. K+ content in the leaves and roots of beth species reduced severely when exposed to NaC1, but the contents in the leaf and root of the mutant was higher than those of the wild type. The Na + dis- tribution in the seedlings of the mutant and the wild type was significantly different. When exposed to salt stress for 96 h, the quantity of the accumulated Na + in root was 44.3 % of the total Na + per seedling of the mutant, whereas it was 24.3% in the wild type, which was likely resulted from the reduction of Na+ transfer from roots to shoots in the mutant.     

多胺浸种改善盐胁迫大麦根系液泡膜功能的机理

研究了0.1 mmol/L 腐胺 (Put) 和0.5 mmol/L 亚精胺 (Spd) 浸种对200 mmol/L NaCl胁迫下大麦(Hordeum vulgare L.)幼苗生长速率、干物质积累、离子分布、液泡膜蛋白结合多胺含量以及液泡膜膜脂组分与功能的影响.结果表明,Put和Spd浸种均可缓解盐胁迫对大麦幼苗的盐害,促进生长和干物质积累,降低大麦幼苗体内[Na+]/[K+].与盐处理的对照植株相比,Put和Spd浸种均可提高大麦幼苗根系液泡膜磷脂含量,降低糖脂结合半乳糖含量,而膜上非共价结合多胺含量Spd+PAx (一种未知多胺) 与 Put+Dap (二氨基丙烷)之比((Spd+PAx)/(Put+Dap))、共价和非共价结合多胺总量均上升.统计分析结果表明,液泡膜非共价结合多胺(Spd+PAx)/(Put+Dap)与H+-ATPase和H+-PPase活性呈显著正相关关系.     

盐胁迫下不同的钙盐对小麦幼苗耐盐性的影响

利用Ｃａ（ＮＯ３）２和ＣａＣｌ２可以提高生长在盐渍条件下小麦幼苗的耐盐能力,增加幼苗的干、鲜重。其原因是由于两种钙盐均能防止膜脂过氧化,降低质膜透性,减少细胞内营养物质外渗,阻止Ｎａ＋进入细胞。实验结果证明,在降低小麦幼苗盐害方面,Ｃａ（ＮＯ３）２好于ＣａＣｌ２。讨论了两个钙盐在降低盐害机理方面的差异     

Effects of Fatty Acids on Lipid Composition and Function of Tonoplast Vesicles in Barley Seedlings Under Salt Stress

When barley ( Hordeum vulgare L. ) seedlings were treated with 100 mmol/L NaC1 for 2 d, the index of unsaturated fatty acid (IUFA) increased in the tonoplast vesicles that were isolated from the seedlings mots of two barley cultivars with different salt tolerance, whereas no change were observed when the seedlings were treated with exogenous fatty acids with different satumbility. Exogenous stearic acid and linoleic acid decreased Na + absorption and transportation to the shoots, increased K + absorption and transportation, decreased the leakage of electrolytes, and increased the phospholipid and galactose contents of lipids in tonoplast, enhanced the activities of tonoplast H+ -ATPase and H+ -PPase. This is consistent with the results that the two fatty acids, linoleic acid and stearic acid, regulate ion absorption and distribution, mitigate salt stress to some extent, the effects of linoleic acid being more the latter.     

Lipid Composition of Whole Roots and of Ca2+, Mg2+-activated Adenosine Triphosphatases from Wheat and Oat as Related to Mineral Nutrition

Lipid composition of whole roots of wheat (Triticum vulgare Vill. cv. Svenno Spring Wheat) and oat (Avena sativa L. cv. Brighton) and of cell wall fractions, mitochondrial fractions and microsomal fractions of these roots were studied. Lipid composition depended upon the level of mineral nutrition. In wheat total phospholipids, phosphatidyl choline and sulfolipid content was highest in the roots grown at the higher salt concentration, while the reverse was true for oat roots. In both species glycolipid and sterol content was lower in the high salt roots, at the same time as higher proportions of them were built into the microsomal fraction. Phosphatidyl choline content of the wheat root membrane fractions increased with the salt level, while the opposite occurred in the oat roots. The phosphatidyl choline content may be correlated with the (Ca²⁺, Mg²⁺)-stimulated ATPase activity.     

Characterization of the lipids of mesosomal vesicles and plasma membranes from Staphylococcus aureus.

Mesosomal vesicles and plasma membranes were isolated from Staphylococcus aureus ATCC 6538P by protoplasting and differential centrifugation. The lipids of each of the two membrane fractions were extracted with pyridine-acetic acid-N-butanol, and the nonlipid contaminants were removed by Sephadex treatment. The lipids were then separated by passage through diethylaminoethyl-cellulose columns and characterized by thin-layer chromatographic, chemical, and spectral analyses. The lipids were separated into four discrete diethylaminoethyl fractions: (i) vitamin K2, carotenoids, C55 isoprenoid alcohol, and monoglucosyl diglyceride; (ii) cardiolipin, carotenoids, phosphatidyl glycerol, diglucosyl diglyceride, and an unidentified ninhydrin-positive component; (iii) cardiolipid and phosphatidyl glyderol; (iv) cardiolipin, phosphatidyl glycerol, and phosphatidyl glucose. Qualitatively, no difference in lipid composition between mesosomal vesicles and plasma membranes was found. However, based on equal dry weights of membrane materials, a relative quantitative difference in the amount of specific lipids in mesosomal vesicles and plasma membranes was observed. There are 4 times more monoglucosyl diglyceride, 2.6 times more diglucosyl diglyceride, 3.8 times more phosphatidyl glucose, 2 times more carotenoids, and 2 times more vitamin K2 found in mesosomal vesicles than in plasma membranes. The concentration of cardiolipin and phosphatidyl glycerol is 3.6 and 6 times greater, respectively, in mesosomal vesicles.     

NaCl胁迫下水杨酸和阿斯匹林对小麦幼苗体内ATP含量的影响

Four wheat ( Triticum aestivum L. ) genotype, "Chinese Spring", "Nongda 85021" (salt sensitive genotypes) and "Chadianhong", "Dong 68"( salt resistant genotypes) seedlings under NaC1 stress were involved. The results showed that, exogenous salicylic acid and aspirin relatively increased the ATP content in wheat seedlings under NaC1 stress, and the increasing range of root was larger than that of shoot, not only in the salt sensitive genotypes but also in the salt resistant genotypes. This suggests that an energy balance is maintained in wheat seedlings under NaC1 stress.     

钙离子对盐胁迫小麦幼苗氮代谢的影响

为探讨增强小麦抗盐能力的调控途径,以普通小麦豫麦34为材料,研究了Ca2+对盐胁迫下小麦幼苗氮代谢及生长的影响.采用全营养液培养小麦幼苗至第一片叶完全展开,更换无钙营养液,并开始不同处理.处理分别为低盐胁迫(150 mmol · L-1 NaCl)、低盐胁迫+4 mmol · L-1 Ca2+、高盐胁迫(300 mmol · L-1 NaCl)、高盐胁迫+4mmol · L-1 Ca2+,以无NaCl胁迫的小麦为对照.5 d后取样,测定了氮同化酶活性、代谢物含量、积累量及幼苗生长状况.结果表明,Ca2+明显缓解了低盐胁迫对小麦幼苗的生长抑制,表现在鲜重、叶绿素及可溶性蛋白含量的增加,而对高盐胁迫下小麦幼苗的生长无明显改善效果;Ca2+改善了低盐胁迫下小麦幼苗的氮营养状况,表现在氮积累量的增加,这一效应主要是通过硝酸还原酶(NR)、谷氨酰胺合成酶(GS)以及异柠檬酸脱氢酶(NADP-ICDH)活性的增强而实现的.Ca2+未能改善高盐胁迫下小麦幼苗氮营养状况的主要限制因子在于NADP-ICDH活性未明显增加.