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1.
Experiments under both greenhouse and field conditions were performed to study the influence of the type of salt applied (KCl or K2SO4) and to compare the effectiveness of their method of application (soil versus foliar) on leaf K concentration and yield in olive trees established under rainfed conditions. In the experiment performed in the greenhouse, mist-rooted 3-month-old ‘Picual’ olive plants growing in 2-l pots containing perlite were irrigated with a complete nutrient solution containing either 0.05 or 2.5 mM KCl during 128 days after transplanting (DAT). A group of plants received one K soil application at a dose equivalent to 1 kg of K per tree at 63 DAT. Another group received four foliar applications at 63, 78, 93 and 108 DAT with a K concentration of 10.5 g/l. The experiment under field conditions was developed with 80-year-old ‘Hojiblanca’ olive trees. Soil application was performed in March every year at a rate of 1 kg K/tree by injecting K fertilizer around the trees. Foliar sprays were carried out in April, March, June and July every year with the same K concentration used for the greenhouse experiment. The results showed that, under both field and greenhouse conditions, either KCl or K2SO4 increased K concentration in leaves. Also, both K salts had a positive effect in increasing K content in fruits under field conditions, although the intensity of the increase varied among years. Tree water stress and low K status seemed to influence K uptake. The method of K application, soil or foliar, did not affect the effectiveness of K fertilization.  相似文献   

2.
以优质番茄品种京采6 号为试材,研究了不同栽培密度（3.8、5.0 株 · m-2）与离子处理（K+、Na+）对基质培番茄生长、产量与品质的影响,构建了番茄果实品质综合评价指数TQI。结果表明：提高营养液中的K+ 浓度,能够在不影响产量的同时增加番茄第2 穗果实可溶性糖、可溶性固形物、糖酸比和VC 含量;栽培密度对番茄产量和品质的影响较小;栽培密度× 离子互作显著影响了第1 穗果实有机酸、亚硝酸盐含量与糖酸比;第2 穗果是生产高品质番茄的关键,其在3.8 株 · m-2与高K+ 营养液条件下可获得最高的TQI。综合来看,建议在实际生产中控制栽培密度为3.8 株 · m-2,同时采用高K+ 营养液灌溉,可在稳产条件下获得高品质番茄。  相似文献   

3.
AIM:To screen the proteins interacting with human augmenter of liver regeneration (hALR) by yeast two-hybrid system and to study the mechanism of hALR action. METHODS:hALR bait plasmid was constructed by ligating the gene of hALR into pGBKT7, then transformed into yeast AH109. The yeast strain AH109 containing pGBKT7-hALR was mated with yeast Y187 containing human liver cDNA library plasmid. Diploid yeast was plated on SD/-trp-leu-his-ade (QDO) for screening and on QDO containing X-α-gal for further selection.The AD/library inserts were amplified by PCR and the PCR products were characterized by digesting with Sau3AⅠ and HaeⅢ restriction enzyme to eliminate the duplicates. After sequencing, the positive clones were analysed by bioinformatics. RESULTS:Several positive clones were obtaind. The sequencing and analysis shown that one of them is 669 bp DNA fragment encoding β subunit of Na+, K+-ATPase. The 224 bp 3'terminal DNA fragment is non-encoder region, and the 445 bp 5'terminal DNA encodes C-terminal 147 amino acid residues of Na+, K+-ATPase β subunit. CONCLUSION:The results of screening proteins using yeast two-hybrid system showed that hALR could interact directly with Na+, K+-ATPase in the yeast cell.  相似文献   

4.
The aim of this study was to evaluate the effects of low molecular mass antioxidants and NaCl salinity on growth, ionic balance, proline, and water contents of ‘Zard’ olive trees under controlled greenhouse conditions. The experiment was carried out by spraying 2 mM of ascorbic acid (Asc) and 3 mM of reduced glutathione (GSH) on the plants that were treated with two salinity levels (0 and 100 mM NaCl) on their root medium. Plant growth parameters (leaf fresh weight, leaf dry weight, leaf number, total fresh weight, and total dry weight) were significantly improved by Asc compared with growth parameters in GSH and control plants. Higher concentrations of Na+ and Cl– were observed in salt-stressed plants, while Na+ and Cl– concentrations were decreased in the olive leaves that were sprayed with Asc. Salinity in the root zone caused a considerable decline in both K+ concentration and K/Na ratio. K+ concentration and K/Na ratio were significantly increased by application of Asc on plant leaves. Salinity caused an increase in electrolyte leakage (EL) compared with the control plants. Lowest EL and tissue water content (TWC) was obtained in Asc-sprayed plants, whereas TWC was increased in salt-stressed plants. Plants were subjected to salt stress and showed a higher relative water content (RWC) than the control plants. Salt stress induced proline accumulation in olive leaves. In conclusion, exogenous application of Asc is recommended to improve tolerance of olive plants under saline conditions.  相似文献   

5.
In order to investigate the effects of spermidine (Spd) and spermine (Spm) on the stress of cadmium chloride (CdCl2), it was checked that the content of polyamines and malondialdehyde (MDA), the rate of superoxide anion (O2−) generation and the activities of superoxidase dismutase (SOD) and guaiacol peroxidase (GPX) in 1-year-old Malus hupehensis Rehd. var. pinyiensis Jiang (tea crabapple) seedlings grown in nutrient solution. The result showed that the content of free putrescine (Put) was increased, the contents of free Spd and Spm and the (Spd + Spm)/Put ratio in leaves were decreased significantly under CdCl2 treatment. Foliar spraying with Spd or Spm under CdCl2 treatment, the accumulation of free Put reduced, the contents of free Spd and Spm and the ratio of (Spd + Spm)/Put in leaves increased significantly. The activities of SOD and GPX in leaves were enhanced and O2− generation rate and MDA content were decreased significantly by foliar spraying with Spd or Spm under CdCl2 treatment. Results suggest that both Spd and Spm can alleviate the lipid peroxidation caused by CdCl2 in M. hupehensis var. pinyiensis.  相似文献   

6.
为探究外源蔗糖对弱光胁迫下南瓜幼苗生长和光合特性的影响,以蜜本南瓜为材料,设置4个处理:正常光照(300μmol·m-2·s-1)下叶面喷施清水(CK),弱光(150μmol·m-2·s-1)下喷施清水(T0)、1%的蔗糖(T1)和2%的蔗糖(T2)。结果表明,与正常光照相比,弱光显著降低了南瓜幼苗的株高、茎粗、生物量、壮苗指数、比叶重等生长指标,以及荧光参数、净光合速率等光合指标。弱光下叶面喷施1%和2%的蔗糖提高了南瓜幼苗的株高、茎粗、生物量、比叶重、叶绿素含量、荧光参数和Pn-PPFD响应曲线及其参数等,其中喷施1%蔗糖增加幅度较大,地上部鲜质量、干质量、比叶重、叶绿素总含量、Fv/Fm、qP、TRO/RC、Ψo、AQY和P_(n max)分别比弱光处理显著增加了28.5%、40.6%、31.3%、5.7%、27.9%、37.5%、3.4%、14.3%、38.5%和34.3%,以上指标喷施2%蔗糖处理与1%蔗糖处理无显著差异。综上所述,弱光下喷施蔗糖可促进南瓜幼苗的生长并有效改善光和性能,且以1%蔗糖处理效果最好。  相似文献   

7.
以园林植物石楠为试材,通过混合2种中性盐(NaCl和Na2SO4)和2种碱性盐(NaHCO3和Na2CO3)分别模拟不同强度的盐、碱胁迫条件,对园林植物(石楠)进行3年(2015—2017年)的胁迫处理,以期探讨盐碱胁迫对园林植物土壤酶活性和微生物的影响。结果表明:1)土壤中有机酸含量随着盐碱浓度的增加呈逐渐降低趋势。随胁迫强度增加,盐、碱胁迫均使土壤中Na+浓度大幅度上升,K+浓度大幅度下降,但碱胁迫下Na+浓度上升幅度和K+浓度下降幅度均大于盐胁迫。2)随着盐碱浓度的增加,土壤中氨基酸类、碳水化合物类、羧酸类、聚合物类、胺类、酚酸类碳源呈逐渐降低趋势,总体而言,碳水化合物和羧酸类碳源是盐碱胁迫下园林植物土壤微生物的主要碳源,其次为氨基酸类、酚酸类和聚合物类,胺类碳源的利用率最小。3)土壤微生物物种丰富度指数(H)、均匀度指数(E)和碳源利用丰富度指数(S)、土壤微生物量碳、微生物呼吸和微生物代谢熵随盐碱浓度的增加而增加。4)土壤糖苷酶、几丁质酶、亮氨酸氨基肽酶、碱性磷酸酶、酚氧化酶δ和过氧化物酶δ随盐碱浓度的增加呈逐渐降低趋势。5)交互作用分析显示,盐胁迫、碱胁迫、盐胁迫×碱胁迫对有机酸、Na+、K+、Na+/K+、物种丰富度指数(H)、碳源利用丰富度指数(S)、土壤微生物量碳、土壤微生物呼吸、土壤微生物代谢熵、糖苷酶和碱性磷酸酶具有显著的影响(P<0.05),其中碱胁迫对土壤酶活性和微生物群落多样性的影响高于盐胁迫,并且盐胁迫×碱胁迫的影响高于单独盐胁迫或碱胁迫.  相似文献   

8.
杨琳  董玲  李明军  马锋旺  邹养军 《园艺学报》2016,43(6):1021-1032
利用苹果基因组筛选K~+转运蛋白基因,分析其系统发育关系,通过q RT-PCR检测它们在平邑甜茶各器官组织和不同发育阶段果实的表达特征。结果表明,在苹果中存在65个K~+转运蛋白基因,包括CHX家族(33个)、HAK家族(24个)、HKT家族(1个)和KEA家族(7个),它们与拟南芥K~+转运蛋白基因高度同源,其基因结构相对保守,并且不均匀地分布在13条染色体上。定量表达分析发现,K~+转运蛋白基因具有不同的表达模式,其中在根中高度表达的32个,在叶片中高度表达的12个,在茎尖中高度表达的11个,在果实中高度表达的19个。研究结果为揭示苹果K~+转运蛋白基因的功能提供了基础资料。  相似文献   

9.
AIM: To study the relaxation effect of isoliensinine on high K+-induced isolated mouse airway smooth muscle (ASM) and the underlying mechanism. METHODS: The muscle tension transducer was used to detect the effects of isoliensinine on high K+-induced precontraction and Ca2+ influx in ASM. The technique of patch-clamp and calcium imaging system were respectively used to examine the effects of isoliensinine on LVDCC currents and[Ca2+]i of the ASM cells (ASMCs). RESULTS: Isoliensinine significantly relaxed precontracted ASM induced by high K+ in a concentration-dependent manner. The maximum relaxation ratio was(95.3±3.9)% by isoliensinine at 100 μmol/L. In addition, LVDCC currents were measured using the whole-cell patch-clamp technique, which were abolished by isoliensinine. High K+-induced 340/380 nm fluorescence ratio of Fura-2 was 0.63±0.10 in ASMCs, while it decreased to 0.36±0.05 after the addition of isoliensinine (P<0.01). When isoliensinine was added at the peak point of[Ca2+]i, the ratio rapidly decreased from 0.74±0.02 to 0.42±0.05 (P<0.01). Moreover, isoliensinine inhibited high K+-induced Ca2+ influx-mediated contraction of ASM. CONCLUSION: Isoliensinine inhibits LVDCC currents, terminates Ca2+ influx and reduces[Ca2+]i, eventually resulting in relaxation of the ASM, indicating isoliensinine might be a potential bronchodilator.  相似文献   

10.
以香瓜茄为材料,在日光温室条件下,于果实发育期叶面喷施沼液肥,研究沼液肥施用浓度及其与土壤追肥配合对香瓜茄叶片光合特性和果实产量与品质的影响。结果表明,稀释100倍沼液肥处理的叶片总氮和叶绿素质量分数分别为35.7 g·kg-1和1.129 mg·g-1,显著高于稀释400倍沼液肥的处理和对照,沼液肥配合土壤追肥时叶片总氮和叶绿素质量分数明显高于只喷施沼液肥的。香瓜茄果实膨大期叶片净光合速率高于开花期和果实成熟期,叶面喷施沼液肥后叶片平均Pn(10.2μmol·m-2·s-1)显著高于对照(7.88μmol·m-2·s-1),沼液肥配合土壤追肥的Pn(10.30μmol·m-2·s-1)显著高于单喷沼液肥处理(8.94μmol·m-2·s-1)。叶面喷施中,高浓度沼液肥能显著提高香瓜茄果实产量和品质,两个土壤施肥处理平均单果质量比对照分别增加16.8%和22.2%,小区产量提高18.9%和30.4%,果肉硬度提高13.9%和23.2%,可溶性固形物含量增加6.9%和15.3%,喷施沼液肥结合土壤追肥处理的效果优于单喷沼液肥。香瓜茄果实生育期配合土壤追肥的沼液适宜喷施浓度为浓缩沼液稀释100倍。  相似文献   

11.
The present work differentiates the effects of NaCl, Cl−, Na+ and concentrated macronutrients on two citrus species, sour orange (Citrus aurantium L) and Macrophylla (Citrus macrophylla Wester). Plants were grown in a base nutrient solution (0.07 MPa osmotic pressure) for 4 months before applying the treatments that consisted of isotonic solutions of 0.23 MPa osmotic pressure of Na+ (40 mM, without Cl−), Cl− (40 mM, without Na+), NaCl (40 mM) and 3.5 times the concentration of macronutrients of the base solution. Plants were grown in the different treatment for 2 months before being examined for symptoms of toxicity. The two genotypes showed major differences in the extent of Cl− and Na+ accumulation in leaves and in their ability to maintain the internal concentrations of essential nutrients in response to the different ionic compositions of the medium. Differences in mineral nutrient accumulation were observed among treatments in both rootstocks. It was concluded that growth response to the different treatments was primarily affected by an osmotic effect, although in Macrophylla, the ionic effects also seem to be present.  相似文献   

12.
比较了耐盐碱的岷江百合（Lilium regale Wilson）和对盐碱敏感的东方百合‘索邦’（‘Sorbonne’）在不同浓度的碱性盐NaHCO3胁迫下叶片的渗透调节物质、活性氧清除物质、离子调节物质（Na+、K+）及有机酸含量的变化,探讨百合耐盐碱的生理机制。研究发现,两种百合叶片中各种物质的变化趋势基本相似,但整体上岷江百合的各种物质含量或者活性均高于‘索邦’。随着NaHCO3胁迫浓度的增加,两种百合叶片中的可溶性蛋白、脯氨酸含量增加,可溶性糖含量先升后降;SOD、GR的活性和AsA的含量先上升后下降,APX的活性和GSH的含量在低浓度胁迫时无明显变化,高浓度胁迫时显著下降;‘索邦’Na+主要积累在成熟叶和新生叶中,岷江百合则主要积累在茎和成熟叶中,且能维持根、成熟叶和新生叶中较高水平的K+/Na+值;岷江百合中的草酸、乳酸和乙酸含量都一直增加或高于对照,‘索邦’中的苹果酸和乙酸含量一直增加。与‘索邦’相比,岷江百合在低浓度NaHCO3胁迫下提高SOD活性和AsA含量,高浓度NaHCO3胁迫下增加可溶性蛋白的含量并保持可溶性糖的稳定性,是其耐盐碱性较强的原因之一。  相似文献   

13.
AIM and METHODS: The sodium ion Na+ and potassium ion K+ selective microelectrodes were used to measure changes of ionic activity of extracellular sodium and potassium( [Na+]o, [K+]o) in hippocampus and hippocampal slice during epieptic seizure induced by intrahippocampal microinjection of coriaria lactone(CL) in rats and perfusing hippocampal slice with CL. RESULTS:30 s, 1min and 2min after injection of CL into hippocampus, the [Na+]o decreased 27.7 mmol/L, 50.3 mmol/L, 57.8 mmol/L respectively and the [K+]o increased 2.3 mmol/L, 2.4 mmol/L, 2.9 mmol/L respectively compared with control values(P＜0.01). The [K+]o returned to the control level 3min after local application of CL, but the[Na+] o was still lower than that of control group(P＜0.01). The [Na+]o and the [K+]o were measured also in hippocampal silces and results are similar to those of experiments in vivo. CONCLUSION: The influx of Na+and the flux of K+occurred during epileptiform discharges of hippocampal neurons induced by administration of CL.  相似文献   

14.
Summary

The responses of leaf water status, growth, and ion concentrations to water or to saline stresses were compared in olive cuttings of different Ca2+ status. Mist-rooted ‘Picual’ olive cuttings were grown in a greenhouse in 2 l plastic pots containing perlite. A nutrient solution with or without 2.5 mM CaCl2 was initially used to irrigate the plants. When the Ca2+-starved plants differed in height from the Ca2+-treated plants, water or saline stress (i.e., no irrigation or 75 mM NaCl, respectively) were applied. The results indicated that Ca2+ increased growth in saline-treated plants, but not in water-stressed plants. After 98 d growth, the stresses were relieved and the plants were irrigated again with or without Ca2+. Growth increased and leaf water status was increased during this recovery period, but no direct effects of Ca2+ were observed in the response of plants to stress-relief. We suggest that the beneficial effect of Ca2+ on tolerance to salt stress in olive plants was related to protection against Na+ toxicity, because there was no response of water-stressed plants to the supply of Ca2+.  相似文献   

15.
AIM:To study the changes of K+ channels of outer hair cells in guinea pig cochlea with streptomycin ototoxicity. METHODS:Auditory brainstem responses (ABR) and whole-cell patch clamp techniques were used.RESULTS:(1) The body weight of guinea pigs with streptomycin ototoxicity decreased significantly; (2) The ABR threshold markedly increased in streptomycin group (Ⅱ,Ⅲ);(3)The number of dissociated outer hair cells of guinea pigs (Ⅱ,Ⅲ) was lower than that of control (Ⅰ); (4) Streptomycin decreased the Ca2+-sensitive K+ currents and delayed outward K+ currents distinctly; (5) There was no significant difference of K+ currents between Ⅰ and Ⅱ/Ⅲ. CONCLUSION:These results suggest that the inhibition of K+ channels is the basis of streptomycin ototoxicity, but not the direct reason for cell death.  相似文献   

16.
以京欣1号为试材,采用Hoagland营养液水培方式,研究不同浓度腐植酸(0、0.1、0.3、0.6、1.0g·L~()-1))对盐胁迫(100mmol·L~()-1)Na Cl)下西瓜幼苗光合特性、叶绿素含量、生物量、电解质渗漏率、抗氧化酶、脯氨酸及Na~+、K~+含量的影响。结果表明:盐胁迫下营养液中添加腐植酸能不同程度改善植株生长状况,以腐植酸浓度为0.3g·L~()-1)时缓解效果最佳,显著提高了盐胁迫下西瓜幼苗的叶绿素含量、光合作用、PSⅡ最大光化学效率(Fv/Fm)和PSⅡ实际光化学效率(ΦPSⅡ),改善了植株体内Na~+、K~+分布,提高了SOD、CAT活性,降低了植株的电解质渗漏率和MDA积累,促进了西瓜植株的生长。  相似文献   

17.
In 2003, highbush blueberry (Vaccinium corymbosum) cultivars ‘Brigitta Blue’ and ‘Nelson’ were treated with a foliar boron-containing, ascofol spray (Wuxal®). After blossoming, the plants were sprayed three times with 0.5% ascofol solution. Control plants were sprayed with tap water. Fruit harvest of each cultivar was on July 19 and 30, respectively. Leaf samples were taken on June 4 and August 7. The boron content of fruits and leaves was analyzed along with fruit yield and single berry weight. The potential absorption rate of applied boron (boron increase in leaves and fruits) was calculated. Foliarly applied boron was readily taken up by the leaves of both cultivars and translocated to the fruits. A potential boron absorption rate of 2.4% was calculated for ‘Nelson’. Foliar application of boron did not increase fruit yield in either cultivar. However, ‘Nelson’ showed a slight increase of berry weight in the second harvest, associated with the boron treatments.  相似文献   

18.
AIM: To investigate the mechanism of quercetin improving rat coronary artery myogenic response under high glucose (HG) by measuring muscle tension of coronary arterial ring and recording voltage-gated K+ channel (Kv) current of coronary artery smooth muscle cells by whole cell patch clamp. METHODS: The coronary rings from the normal SD rats were acutely isolated, and then divided into 6 groups: (1) control group; (2) HG group; (3) HG+low dose (3 μmol/L) of quercetin group; (4) HG+moderate dose (10 μmol/L) of quercetin group; (5) HG+high dose (30 μmol/L) of quercetin group; (6) HG+C6303 (PKC inhibitor)+high dose of quercetin group. Determinations of coronary artery response to vasoconstrictor (60 mmol/L KCl or 0.1 mmol/L U46619) or vasodilator (ACh at 10-9~10-5 mol/L) were performed, and the percentage of coronary ring tension was calculated using the contraction as 100% caused by 60 mmol/L KCl. The rat coronary artery smooth muscle cells were acutely isolated for recording the Kv current using whole cell patch clamp. RESULTS: Compared with control group, the contraction amplitudes to 60 mmol/L KCl or 0.1 mmol/L U46619 were significantly increased under HG incubation. Quercetin intervention concentration-dependently reduced the coronary artery contraction amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, the diastolic amplitude to ACh decreased significantly in HG group, and quercetin intervention concentration-dependently increased the coronary artery diastolic amplitude. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. Compared with control group, HG incubation inhibited Kv current of coronary artery vascular smooth muscle cells significantly, and quercetin intervention attenuated the inhibitory effect of HG on Kv current intensity. Incubation of PKC specific inhibitor C6303 attenuated the effect of quercetin. CONCLUSION: Quercetin has a protective effect on myogenic response of coronary artery under HG and the effects is related to the increase in Kv current and the activation of PKC in vascular smooth muscle cells.  相似文献   

19.
Boronia (Boronia megastigma Nees, family Rutaceae) is an Australian woody shrub, producing strongly scented flowers at nodes. Increasing N levels from 0 to 25 mM in the nutrient solution increased the production of nodes, lateral shoots from these nodes and further nodes on these lateral shoots. With the same level of N, the order of number of node and lateral shoot production by N form was: combined NH4+plus NO3− > NH4+alone > NO3− alone. This increase in the number of nodes subsequently translated into increased number of axils initiating flower buds and then into fully developed flowers. However, increasing N levels decreased the percentage of flower buds developing to anthesis and individual flower weight. These decreases were attributed to continued vegetative growth during flower development. Increasing N levels increased the leaf N concentration with the concentration in the order NH4+ + NO3− > NH4+ > NO3−. Nitrogen form did not affect the leaf tissue concentration of P, K+, Ca2+ and Mg2+. At lower N levels, the concentrations of these nutrients in the leaf tissue were higher and may have reached toxic levels, causing toxicity symptoms on leaves. At higher N levels, the concentrations of these nutrients were diluted due to increased growth and no toxicity symptoms were produced.  相似文献   

20.
AIM:To investigate the role of K+ channels in the decreased hypoxic pulmonary vasoconstriction(HPV) in chronic hypoxic rats. METHODS:Blockers of three kinds of K+ channels, 4-AP(voltage dependent K+ channel blocker), TEA(Ca2+ activated K+ channel blocker), GLIB(ATP sensitive K+ channel blocker) were used in isolated perfused rat lungs to detect the role of K+ channels in HPV. RESULTS:In normal rats, 4-AP and TEA, but not GLIB, both elicited a significant increase in pulmonary artery baseline pressure, and also potentiated the acute hypoxic pulmonary vasoconstriction. In chronic hypoxic rats, the HPV is significantly decreased, while 4-AP, TEA, GLIB all elicited a significant but smaller increase in pulmonary artery baseline pressure. Additionally, all these three blockers potentiated the HPV stronger in chronic hypoxic rats than in control rats. CONCLUSION:The opening of Kv, KCa, KATP might modulate the hypoxic pulmonary vasoconstriction in isolated rat lungs, and the increase in this modulation by potassium channel in chronic hypoxic rats might play a role in its decrease in HPV.  相似文献   

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