NaCl胁迫对黄芪种子萌发及幼苗生长的影响

研究不同浓度NaCl的处理下,对黄芪种子萌发及幼苗生长的影响.结果表明：低浓度盐处理有利于促进种子萌发,对幼苗的生长也未表现出不利影响;随盐胁迫浓度的增大,黄芪种子发芽率、发芽指数、幼苗的生长在形态上都表现出盐害效应.     

海藻糖对NaCl胁迫下多年生黑麦草苗期生长和离子平衡的影响

以萌发15d的多年生黑麦草小苗为试验材料,采用全组合试验设计,研究了外施海藻糖(0、0.2%、0.6%)对不同NaCl浓度(0、0.5%、1.0%)胁迫下黑麦草生长和离子平衡的影响。结果表明:(1)适宜的海藻糖浓度(0.2%)显著(p0.05)提高了高盐(1.0%NaCl)胁迫下黑麦草的分蘖数,缓解了高盐对其生长的抑制作用;(2)0.6%海藻糖处理显著(p0.05)增加了0.5%和1.0%盐胁迫下的叶重比,但降低了根重比和根冠比。(3)高盐(1.0%NaCl)胁迫下,0.2%海藻糖处理的植株,K+含量明显高于其他处理,海藻糖促进了K+在根中的积累。外施0.2%海藻糖对相同盐浓度胁迫下各海藻糖处理中K+/Na+比率最高。     

NaCl胁迫对不同种源海州常山生长及离子吸收、分配与运输的影响

以江西萍乡、山东平度、江苏盐城3个种源地的海州常山组织培养苗为材料,采用不同浓度NaCl进行胁迫处理,分析其对海州常山生长、离子选择吸收和运输的影响,探讨不同种源海州常山的耐盐差异和耐盐机理。结果表明:(1)NaCl胁迫下,海州常山生物量下降,含水量降低,生长受到抑制;(2)随着NaCl浓度上升,Na~+的吸收为先升后降,高浓度NaCl胁迫下,江西萍乡种源Na~+主要集中在叶柄中,而山东平度种源Na~+主要集中在茎部;K~+含量随着NaCl胁迫的增加呈下降的趋势,在叶片中含量较高;K~+/Na~+随NaCl浓度的增加呈下降趋势;(3)随着NaCl浓度增加,根系选择吸收系数SAK,Na、离子运输系数STK,Na先增后降(山东平度茎秆运输除外),总体而言,盐城种源SAK,Na,STK,Na的值大于其他种源,根抑制Na~+、促进K~+向地上部运输的能力也较其他种源强。综合分析表明:高浓度的盐胁迫对不同种源均产生不利影响,造成植物体内盐离子积累,但盐城种源保持体内离子平衡能力和耐盐性高于其他种源。     

NaCl胁迫对榉树种子萌发及幼苗生理指标的影响

研究了0.1%、0.2%、0.4%、0.6%和0.8%NaCl浓度处理对榉树种子萌发和幼苗生理指标的影响.结果显示:榉树种子的发芽率,发芽指数和活力指数在较低NaCl浓度(0.1%)处理下即有显著降低;萌发后幼苗的苗高、根长在较低NaCl浓度(≤0.2%)处理下变化不显著,当NaCl浓度达到0.4%及更高对幼苗的苗高和根长显著减小;幼苗SOD、POD活性随NaCl处理浓度的增加呈先升后降的单峰曲线,MDA含量变化不明显.由此推断,榉树在种子萌发阶段对NaCl胁迫较为敏感,但萌发后的幼苗在较低NaCl浓度(0.2%)下可通过增加保护酶的活性来减少NaCl胁迫产生的危害,从而得以正常生长.     

NaCl胁迫对构树种子发芽及幼苗生理生化指标的影响

研究了不同浓度NaCl(0,25,50,75,100,125 mmol/L)对构树种子发芽和幼苗生长及生理效应的影响.结果表明:低浓度(25 mmol/L)盐胁迫下,构树种子的发芽率比对照升高了7.7%,同时幼苗根长亦有显著增加,比对照高23%,苗高、发芽指数、活力指数虽有所下降但不显著;随着NaCl浓度的增大,构树种子的发芽率、发芽指数、活力指数均呈下降趋势,发芽后幼苗的根长、苗高、鲜质量等也呈下降趋势,幼苗生长被抑制.对幼苗的生理指标测定显示:细胞膜透性随着盐浓度的增加逐渐升高,细胞膜稳定性受到破坏;MDA含量、SOD、POD活性随盐浓度的增加呈现先升高后降低的趋势,膜透性和MDA含量与SOD活性呈极显著相关.     

NaCl胁迫对杨树插穗生长的影响

本研究选择小黑杨、迎春5号杨和中绥12号杨3个杨树品种在添加不同质量浓度NaCl溶液的基质中进行了扦插试验,调查生长情况,进行了统计分析。结果表明：随着NaCl溶液质量浓度的升高,3个杨树品种插穗的新梢长度、叶片数量、根数、根长、插穗地上及其地下部分鲜重和干重等均呈现出逐渐降低的趋势。品种间插穗新梢长度、叶片数量、根长、地上部分鲜重和干重、地下部分鲜重和干重差异达到极显著性水平(F值分别为12.88^**、10.91^**、22.96^**、148.60^**、27.01^**、29.40^**、31.55^**),NaCl溶液质量浓度间插穗新梢长度、叶片数量、根数、根长、地上部分鲜重和干重、地下部分鲜重和干重差异达到极显著性水平(F值分别为11.63^**、10.45^**、13.10^**、10.12^**、43.22^**、10.80^...     

NaCl胁迫对金莲花种子萌发的影响

以金莲花种子为试验材料,测定发芽率、发芽势、发芽指标等生理指标,研究了不同浓度NaCl对金莲花种子萌发的抑制作用。结果表明:金莲花种子萌发可以耐受的最大NaCl浓度为0.9%,高浓度对其萌发具有明显的限制作用。     

刺槐幼苗非结构性碳水化合物对NaCl胁迫的动态响应

【目的】研究NaCl胁迫下的刺槐非结构性碳水化合物(NSC)动态变化,揭示其对NaCl胁迫的适应机制,为刺槐林经营管理提供依据。【方法】以1年生刺槐苗为研究对象,通过盆栽试验,研究不同NaCl浓度(0、1.5‰、3‰、4.5‰)下苗木的相对生长速率、生物量分配和NSC含量的变化规律。【结果】1)随着土壤NaCl浓度增加,刺槐苗木的地径和苗高相对生长速率显著降低;随着NaCl胁迫持续时间增加,叶生物量的增速逐渐降低,而根生物量增速变化不显著,导致叶生物量比显著降低,根生物量比和根冠比显著增加。2)随着土壤NaCl浓度的增加,粗根、细根、茎和叶中的NSC(可溶性糖、淀粉)含量在土壤NaCl浓度3‰以下梯度间差异不显著,但达到4.5‰各个器官中的NSC含量均显著下降,粗根的淀粉含量显著高于细根、茎和叶。3)相关分析表明,地径和苗高相对生长速率与叶生物量比、粗根可溶性糖呈显著正相关(P<0.05),与根生物量比和根冠比呈极显著负相关(P<0.01);粗根淀粉与细根可溶性糖和茎可溶性糖、茎淀粉与茎可溶性糖有着显著正相关(P<0.05),说明NSC动态变化影响生物量分配进而影响器...     

山东稀有植物小果白刺天然群体表型变异研究

[目的]研究山东小果白刺的表型变异程度及变异规律。[方法]采用方差分析、相关分析、聚类分析等分析方法,对山东小果白刺5个群体种实和叶片的10个表型性状进行了比较分析。[结果]群体内变异是山东小果白刺表型变异的主要来源;各性状群体间表型分化系数的变幅为20.20%60.70%,平均值为40.71%;所有性状的变异系数平均值为9.34%,各器官的表型变异程度有叶片大小(8.99%)﹥种子大小(7.74%)﹥果实大小(6.77%)和种子形状(10.22%)﹥叶片形状(6.70%)﹥果实形状(4.35%);小果白刺10个表型性状间大多呈显著或极显著的相关关系;5个小果白刺群体被聚合成2类。[结论]山东小果白刺种实及叶片表型性状在群体间和群体内存在丰富的表型变异,其地理变异规律遵照随机变异模式。该研究结果为小果白刺种质资源的保存提供了依据。     

盐胁迫对红楠幼苗生长及Na+、K+吸收和分布的影响

In order to explore the salt tolerance mechanism of Machilus thunbergii, the effects of salt stress on seedling biomass, root morphology, sodium and potassium absorption and distribution were studied. The results showed that the above-ground biomass increased slightly under lower salt stress conditions, while the below-ground biomass, root length and root surface area showed a downtrend. The above-ground growth was limited under high concentration salt stress, while the under-ground growth was not subject to significant restrictions. The absorption of Na⁺ in root increased under salt stress, but that of K⁺ decreased. The ability of Na⁺ transporting from root to leaf and stem was weakened. The accumulation of Na⁺ in stem and leaves was less. With the decreased absorption of K⁺, the ratio of Na⁺/K⁺ also continuously increased. With the increased concentration of salt stress, the ability of K⁺ absorption in roots increased. The ability of K⁺ transporting from root to leaf and stem was enhanced, which resulted in significant increase of K⁺ in the leaves and stem. The accumulation of Na⁺ in the under-ground was significantly greater than that in above-ground, while the K⁺ content in above-ground increased significantly, which played a key role in maintaining normal growth and metabolism of M. thunbergii.     

苗木蒸腾和Na+吸收对切根及NaCl处理的响应

盐碱地造林时根系伤口对盐分吸收有无影响至今未见报道.本研究在150 mmol NaCl处理的水培条件下,切断供试苗木的吸收根,通过检测叶被害率、蒸腾速率及苗木根、枝干和叶中Na 含量,进一步阐明蒸腾和Na 吸收对切根及NaCl处理的响应.试验结果表明:(1)青栲和金木犀两树种的切根处理都使Na 含量和含有率增大,导致叶被害率升高;(2)与对照及不切根做NaCl处理及切根后3 d做NaCl处理相比,切根后立即进行NaCl处理的苗木,Na 的吸收显著增多,苗木盐害最重,蒸腾速率降低的幅度也最大;切根后放置3 d,Na 吸收和盐害明显受到抑制;(3)随着蒸腾速率的增大,青栲和金木樨的Na 吸收量都增加,且金木樨的二者的相关关系呈极显著(r= 0.613**,n=18).这为盐碱地造林措施的改进提供了理论依据,即在盐碱地造林时最好采用不需要修剪根系的苗木,如果确有修剪的必要,也要在修剪并经过几天圃地的假植后再行种植,避免盐分被迅速吸收,使苗木遭受盐害.     

NaCl胁迫下沙枣幼苗的离子代谢特性

[Objective]To further understand the ion metabolism characteristics of Elaeagnus angustifolia L. under NaCl stress.[Method]The seedlings of two E. angustifolia L. provenances, which were Alaer (salt tolerance provenance) and Yinchuan (salt sensitive provenance), were treated by three NaCl concentrations (0,150,300 mmol·L^-1) and sampled at the 7th day and the 30th day to measure the Na⁺ , K⁺, Ca²⁺, and Mg²⁺ contents, K⁺/Na⁺ ratio and selective absorption and transportation of K⁺ in tissues (roots, stems and leaves). [Result]The results showed that the Na⁺ content in the organizations of E. angustifolia L. sharply increased with the increase of NaCl concentration. With prolonging of stress time, the Na⁺ content increased in roots, and decreased in stems and leaves. After seedlings of the two provenances were treated with 150 mmol·L^-1 NaCl for 7 days, the Na⁺ content was 2.10 times and 2.23 times in leaves, respectively, compared with the control groups, and was 1.79 times and 1.57 times in root. Meanwhile, the difference between two provenances showed a expanding trend with the increase of NaCl concentration and stress time. With the increase of NaCl concentration and extension of stress time, the K⁺ content, Ca²⁺ content and K⁺/Na⁺ ratio in organizations decreased gradually. Meanwhile, the Alaer provenance seedlings accumulated more Na⁺ in roots and less Na⁺ in leaves than that of Yinchuan provenance, and the K⁺ content, Ca²⁺ content and K⁺/Na⁺ ratio decreased less in the Alaer provenance seedlings than those of Yinchuan provenance. With the increase of NaCl concentration, the Mg²⁺ content in leaf gradually decrease, but the Mg²⁺ content in root increased 22.8~64.4% after salt stress for 7 days, and Alaer provenance seedlings increased more than Yinchuan provenance. After 30 days, there was non-significant difference with the control group on the Mg²⁺ content of root. K⁺ selective absorption of E. angustifolia L. seedlings significantly increased with increasing salt concentration of the media at the 7th days, whereas not obvious at the 30th days. When the concentration of NaCl in the media increased, the change of K⁺ selective transportation was not significant. [Conclusion]E. angustifolia L. seedlings increase Mg²⁺ content and K⁺ selective absorption in the roots at the early stage of salt stress to adapt saline environment. The salt-tolerance E. angustifolia L. provenance can cut off more Na⁺ in roots and reduce Na⁺ content in leaves, which cause less K⁺, Ca²⁺ and Mg²⁺ contents loss, especially the roots and leaves, so as to ensure that all kinds of metabolisms can go well.     

白刺幼苗芽库及枝系构型对不同氮添加水平的响应

[目的]研究不同氮添加梯度下白刺幼苗芽库组成及空间结构的差异,探讨了幼苗的养分限制、氮素利用以及根系和插穗的品质与芽库的关联,阐明了白刺芽库响应氮素有效性所采取的适应性策略。[方法]本研究通过盆栽控制实验,对唐古特白刺幼苗的芽库特征进行了测量分析。[结果]氮添加显著增加了白刺幼苗芽和营养枝数量,显著降低了休眠芽和休眠枝数量,并对二级枝和三级枝出芽率具有明显促进作用;随着氮添加量的递增,营养枝有从基部向顶端移动趋势;氮平衡指数与白刺幼苗出芽强度、分枝强度、二级枝和三级枝出芽率均呈二次非线性正相关关系;植株氮含量、氮积累量和地下部分形态特征分别与芽和营养枝数量呈正相关关系,与休眠芽和休眠枝数量呈负相关关系。[结论]氮添加影响幼苗芽库容量。随着氮添加水平的提高,各指标多数在N3和N4处理达到最大值后逐渐降低,因此6个氮添加水平中36 mmol·L-1和48 mmol·L-1是白刺幼苗最适氮添加量。氮添加对幼苗芽库内组分的相对位置产生了不同影响趋势,所以白刺幼苗可以通过改变芽库容量和空间分布来响应养分有效性变化。     

沙埋对白刺表型可塑性的影响

[目的]为研究沙埋对白刺形态、生物量分配及光合特性的表型可塑性的影响,[方法]对扦插白刺,进行0、5、10、15 cm沙埋处理,待生长季结束后,收集数据进行统计分析。[结果]表明:随着沙埋深度的增加,(1)株高、15 cm基径呈减小趋势,不定根长与不定根直径呈先增大后减小的趋势。当沙埋深度为0、5、10、15 cm时,植株的株高依次为62.82、55.90、52.38、49.24 cm,15 cm处基茎依次为2.79、2.48、2.39、2.07 mm,叶面积依次为477.81、214.38、247.90、112.91 cm~2,叶片数依次为700.2、334.40、344.00、216.20片,不定根数依次为6.40、3.80、2.80、3.40根,不定根长依次为10.19、11.54、13.92、7.62 cm,不定根直径依次为1.51、1.95、1.65、1.19mm;(2)枝与叶生物量、总生物量呈减小趋势,而地下部分生物量呈先增大后减小的趋势,地上生物量/地下生物量呈先减小后增大的趋势。当沙埋深度为0、5、10、15 cm时,植株的枝生物量依次为6.29、4.20、3.09、2.75 g,叶生物量依次为3.93、2.52、3.31、1.28 g,总生物量依次为10.81、7.53、7.41、4.30 g,地下部分生物量依次为0.59、0.81、0.59、0.28 g,地上生物量/地下生物量依次为17.32、8.30、10.85、14.39;(3)净光合速率、蒸腾速率和气孔导度的日均值呈依次增加的趋势,如沙埋深度为0、5、10、15 cm时,净光合速率的日均值依次为8.06、9.39、9.72、11.25μmol·m~(-2)·s~(-1),蒸腾速率的日均值依次为5.56、6.70、6.77、7.61 mmol·m~(-2)·s~(-1),气孔导度的日均值依次为0.28、0.31、0.31、0.36 mol·m-2·s-1。(4)沙埋深度5.10 cm白刺的叶绿素a、叶绿素b、叶绿素(a+b)含量与对照组0 cm的差异不显著,当沙埋深度为15 cm时,叶绿素含量显著增大,但叶绿素a/b值的变化不显著。[结论]白刺形态、生物量分配以及叶绿素含量对不同沙埋深度的可塑性较强,当沙埋深度为15 cm时,光合指标对沙埋才会产生显著差异。     

Genotypic Differences in Antioxidative Stress and Salt Tolerance of Three Poplars Under Salt Stress

To evaluate genotypic difference in antioxidative ability and salt tolerance in poplars, the authors investigated the effects of increasing content of soil NaCl on salt concentration in leaves, superoxide dismutase (SOD) and peroxidase (POD) activities, malondialdehyde (MDA) content, and membrane permeability (MP) in Populus euphratica Oliv., P. popularis “35–44,” and P. × euramericana cv. I-214 (hereafter abbreviated as P. cv. I-214). Na⁺ and Cl⁻ concentrations in leaves of P. popularis increased markedly over the increase of the duration of exposure to salinity, and culminated after 28 days of salt stress. SOD and POD activities declined correspondingly, followed by significant increases of MDA and MP, and leaf injury was finally observed. Compared with P. popularis, leaf Na⁺ and Cl⁻ in P. cv. I-214 exhibited a trend similar to P. popularis, but a lower salt-induced increase of MDA and permeability was observed and lighter leaf necrosis occurred. In contrast to P. popularis and P. cv. I-214, SOD and POD activities in P. euphratica leaves increased rapidly at the beginning of salt stress with a light soil NaCl concentration of 58.5 mmol/L. Furthermore, salt ion concentration, MDA content, and MP in P. euphratica leaves did not increase significantly during 28 days of increasing salt stress. Therefore, the increase in MP in P. popularis and P. cv. I-214 had a close relationship with a salt buildup in leaves under increasing salt stress. Salt-induced declines of SOD and POD activities might accelerate lipid peroxide and consequently resulted in ion leakage. P. euphratica rapidly activated antioxidant enzymes after the onset of salt stress, which might reduce the accumulation of reactive oxygen species and the subsequent acceleration of lipid peroxide. P. euphratica leaves exhibited a higher capacity to exclude salt in a longer period of increasing salinity, thus limited salt-induced lipid peroxide and MP, which contributed to membrane integrity maintenance and salt tolerance of P. euphratica. Translated from Journal of Beijing Forestry University, 2005, 27(3) (in Chinese)     

内蒙古西伯利亚杏核仁表型变异及优株选择

[目的]以西伯利亚杏优良单株为选择目标,结合地理生态因子对核仁表型和成分性状的变异规律进行研究,明确内蒙古西伯利亚杏核仁形态及成分的变异特点和地理变异规律,并在此基础上进行不同类型优良单株的选择。[方法]结合单株产量高、生长势好等指标,对来自内蒙古地区的10个西伯利亚杏种源中筛选出的217个单株的核纵径、核横径、核侧径、核壳厚、核形指数、核干质量、仁纵径、仁横径、仁侧径、仁形指数、仁干质量、出仁率、产仁量、粗脂肪、粗蛋白、苦杏仁苷等16个形态及成分性状进行方差分析、多重比较、相关分析、聚类分析、主成分分析,筛选不同类型的优良单株。[结果]表明:(1)西伯利亚杏各性状存在较大变异,变异范围为8.94%68.27%,核形态的变异系数(16.87%)大于仁成分(14.61%)和仁形态(14.14%),质量和成分性状的变异程度高于大小和形状指数。(2)产仁量、仁干质量、出仁率、粗脂肪、粗蛋白、苦杏仁苷等主要经济性状在种源间差异极显著,将种源分为5类,第Ⅰ类群产仁量高、仁大;第Ⅱ类群出仁率高,粗蛋白含量高;第Ⅲ类群粗脂肪和苦杏仁苷含量高;第Ⅳ类群各项指标都较低;第Ⅴ类群产仁量高、粗脂肪和苦杏仁苷含量高。(3)核、仁性状之间存在广泛的相关性,且产仁量、苦杏仁苷、粗脂肪分别与纬度、经度、年平均气温密切相关。(4)前6个主成分贡献率达到80.716%,按5%入选率分别筛选出9种类型的优良单株各11株,各类型优株主成分得分值的现实增益为146.12%199.22%,具有显著的优异性。[结论]内蒙古西伯利亚杏在广泛且多样的地理环境中形成了丰富的核仁表型和成分的变异,且不同种源以及不同个体间存在极显著差异;利用主要经济性状对种源进行了聚类分析,得到5个具有不同经济特征的育种类群;主要经济性状与表型以及地理环境因素密切相关。     

盐胁迫下沙枣生物固氮能力及氮素分配研究

[目的]应用15N自然丰度法研究盐胁迫条件下沙枣的生物固氮能力,并探讨几个耐盐树种的氮素分配情况。[方法]通过耐盐树种的室内砂培试验,确定盐渍生境条件下以空气氮为唯一氮源的沙枣15N相对丰度B值及其适宜的参比植物;估测室内和野外盐渍生境中沙枣的生物固氮能力;并通过测定碳、氮、磷元素含量探讨了几种耐盐树种的氮素分配情况。[结果]室内盐胁迫砂培试验条件下,沙枣的B值为-1.41‰;柽柳和白蜡可作为沙枣的参比植物;沙枣的生物固氮百分率为55.03%。野外中度盐渍环境中,沙枣生物固氮百分率为69.69%。试验条件下,沙枣、柽柳和白蜡3个耐盐树种中,沙枣植株及其叶、茎、根含氮量最高,且与其它树种差异显著(P0.05);沙枣植株氮/碳含量比以及氮/磷含量比最高;沙枣叶、茎和根的氮/磷含量比最高。野外中度盐渍环境中,沙枣叶的氮/碳含量比以及氮/磷含量比均为最高。[结论]15N自然丰度法可用于研究盐胁迫条件下沙枣的生物固氮能力,柽柳和白蜡可作为参比植物;沙枣在盐胁迫下的固氮能力较强,是可应用于盐渍土生物改良的优良树种。本文为盐胁迫条件下利用15N自然丰度法研究生物固氮作用提供方法参考,对于盐碱地生物治理中植物材料的选择和耐盐树种资源的综合开发利用具有重要意义。