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受人类对土地过度垦殖及不合理耕作利用的影响,水土流失正在成为制约我国东北地区耕地可持续利用和粮食生产的主要因素。在对历史资料甄别与整理的基础上,分析近代以来东北3省区人口、土地利用变化及其与水土流失关系的演变。结果表明:到20世纪中期,东北地区人口压力达到60~70人/km2,伴随着生活方式的转变,机械化技术的应用,林草湿地被垦殖,森林覆盖率降到30%,垦殖率达30%,使区域性水土流失问题日益严重。

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用核磁共振(NMR)波谱、HPLC和化学定磷法研究了稀土元素对3'-腺嘌呤核苷酸(3'-AMP)及3'-鸟嘌呤核苷酸(3'-GMP)的水解断裂作用,结果表明:不同稀土元素对3'位核苷酸断裂有较强的特异性,在37℃,pH9的条件下,使3'-AMP断裂为腺嘌呤核苷(A)及无机磷,使3'-GMP断裂为鸟嘌呤核苷(G)及无机磷,其断裂作用远大于5'位核苷酸,并对其水解断裂进行了研究.

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本书阐明了板壳断裂理论的基础。论证了Reissner型板壳断裂理论的科学性、经典板壳断裂理论的缺陷及在一定范围内仍具有的实用价值;介绍了作者所创意的研究Reissner型板壳断裂纹尖端场的方法等。

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通过野外采集和观察,标本鉴定和实验研究,从植物形态学,叶柄和根状茎的解剖,叶表皮的显微观察,和孢子形态的扫描电镜观察等方面进行研究与分析,对中国瓦韦属(除薄叶组)进行了分类学修订研究。 1. 形态性状分析 研究了国内外重要标本馆的大量瓦韦属植物标本,通过对一些重要的形态性状的观察和分析,判定其变异规律及分类学意义。根状茎上的鳞片和孢子囊上的隔丝的形状和网眼结构是瓦韦属属下分类和种的划分的最主要的形态学性状。其它特征如孢子囊群着生的位置、中脉的颜色、根状茎直立或横走等在种内也具有一定的稳定性,可以帮助种的划分和鉴定。因此,在对瓦韦属植物进行分类时要结合几个相关性状而不是单一的性状进行分类。 2. 叶柄和根状茎的解剖 对瓦韦属(除薄叶组)49 个种的叶柄和根状茎进行解剖观察,发现叶柄中维管束的条数一般为1--7 条不等,排成一字形、三角形或半圆形。两根粗的维管束排列在腹面,较细的维管束排列在背面。叶柄中没有厚壁组织,但是在叶柄和根状茎的连接部位叶足处有厚壁组织的存在。根状茎横切面观察显示除了维管束外还有厚壁组织的存在,在常绿种内厚壁组织较多,落叶类型中厚壁组织较少。 3. 叶表皮形态 观察了瓦韦属51 个种的叶表皮形态和结构,发现该性状对于属下划分具有一定的系统学意义,也有助于疑难物种的鉴别。瓦韦属植物的叶表皮细胞形状通常为多边形、不规则;垂周壁式样为波状和浅波状;气孔器类型比较复杂,在所观察的类群中,气孔器都分布在下表皮上,极细胞型Polocytic type,共环极细胞型Copolocytic type ,腋下细胞型Axillocytic type ,聚腋下细胞型Coaxillocytic 是最常见的类型,不规则型Anomocytic type ,不规则四细胞型Anomotetracytic type,不等细胞型Anisocytic type,辐射状细胞型Actinocytic type 和双环不等四细胞型Amphicycloanisocytic type 也存在于瓦韦属的叶表皮中。属下同一个组的叶表皮特征近似,不同的组具有一定的差别。 4. 孢子形态 在扫描电镜下对瓦韦属50 个种的孢子形态进行了观察。瓦韦属的孢子两侧对称,极面观为椭圆形,赤道面观为肾形、豆形或半圆形。孢子的表面纹饰可以分为6 类,分别是光滑、颗粒状、瘤状、皱状、波状以及疣状的纹饰。瓦韦属的孢子周壁较薄,纹饰由外壁组成。孢子形态具有重要的系统学意义,可以为属下分类提供可靠的证据,对形态近似的物种的划分也有重要参考价值。 通过对大量标本的研究,以及模式标本的考证,结合野外居群观察,综合分析有关分类学资料,主要依据比较稳定的微观性状,对瓦韦属植物进行了新的分类学修订。结果承认中国瓦韦属(除薄叶组)有37 种,可以分为5 个组,有3 个名称被首次处理为异名,另有2 个种暂时存疑。

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本论文由三部分组成: 1) 大豆高产品种黑农40与低产品种黑农37不同发育时期叶片光合生理生态特性的研究;以不同产量水平的东北大豆黑农40和对照品种黑农37为试验材料,研究了从幼苗期到衰老期五个不同发育时期叶片光合作用特性的变化。尤其是系统的研究了光合作用、蒸腾作用和水分利用效率的变化之间的联系,以及气孔导度和胞间CO2浓度的相随变化。发现净光合速率和产量之间存在明显的正相关关系,各个光合生理生态参数之间也有密切的关系。 2) 在大豆生长过程的重要时期结荚期,对大豆品种黑农37和黑农40的光合和水分特性的日变化研究;测定结荚期黑农37和黑农40的光合作用、蒸腾作用、气孔导度和水分特征(水分利用效率和水势)的日变化以及它们之间可能存在的联系,并分析了光抑制的现象,研究表明在晴朗的一天中,光合速率的日变化呈双峰曲线,在整个日变化中,黑农40的净光合速率都比黑农37的要高。黑农40和黑农37相比,在水分亏缺的情况下黑农40能维持较高的水势和水分利用效率,特别是在中午的时候,差别更加明显。 3) 比较研究了1970s 、1980s 和1990s 期间不同大豆 (Glycine max (L) Merr.)品种的生理生态特性:光合作用、蒸腾作用、水分利用效率和叶片水势,分析了各生理生态特性之间以及与产量的关系。研究表明光合速率和产量之间存在显著的相关关系,大豆叶片水势和净光合速率之间也存在明显正相关关系,高产大豆在水分亏缺的情况下仍能维持较高的的水分利用效率和水势。

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本论文由三部分组成,一、大豆高产品种黑农40与低产品种黑农37不同发育时期叶片光合功能的比较研究。二、大豆非叶器官豆荚的光合特性。三、不同大豆品种叶片和非叶器官光合特性的比较分析。 一、 黑农40和黑农37不同发育时期叶片的光合特性。 以不同产量水平的东北大豆黑农40和对照品种黑农37为试验材料,研究了从幼苗期到衰老期五个不同发育时期叶片光合作用特性的变化。尤其是比较系统地研究了C4途径的表达,并通过相关分析,发现C4途径酶的活性与大豆的光合效率及其产量密切相关。主要研究结果如下: 1.测定不同发育时期大豆叶片净光合速率、DCIP光还原活力和1,5-二磷酸核酮糖羧化酶(RuBPcase)活力,结果表明,黑农40和黑农37叶片净光合速率均在初荚期达到最高值,而且不同发育时期的黑农40叶片光合能力均强于黑农37。 2.随着大豆叶片的发育和衰老,其叶绿素、类胡萝卜素的含量及Chla/b比值有一个逐渐升高,而后降低的过程。在同一发育时期,高产高光效品种黑农40光合色素含量均高于黑农37,有助于黑农40捕获更多的光能供光合作用所利用。 3.叶绿体吸收光谱及四阶导数光谱表明在整个生育期内以初荚期叶片对光能的吸收能力最强;而每一个发育时期黑农40叶片对光能吸收的能力均比黑农37高。荧光动力学参数表明,高产大豆黑农40叶片PSII活性(Fv/Fo),光化学猝灭系数(qP)及PSII总的光化学量子产量也均高于对照品种黑农37的相应值:而黑农40的非光化学猝灭系数(qN)低于黑农37。说明高产大豆叶片具有与产量潜力相关的较高光能吸收和原初转化能力。通过对叶片及其叶绿体低温(77K)荧光发射光谱特性的分析表明,黑农40叶绿体对两个光系统之间激发能的调节能力优于黑农37。总之,黑农40对光能的吸收、传递和转化能力高于黑农37,从而能为碳同化提供更多能量。 4.通过研究苗期、开花期、初荚期、鼓粒期和衰老期等发育阶段的黑农40和黑农37叶片中磷酸烯醇式丙酮酸羧化酶(PEPCase)、NADP-苹果酸脱氢酶(NADP-MDH)、NADP-苹果酸酶(NADP-ME)、丙酮酸磷酸双激酶(PPDK)等C4途径的关键酶的活性变化,结合同位素14CO2喂饲试验,证明两种大豆叶片均含有C4途径四种关键酶,其原初产物含有有限的有机酸,说明有C4循环存在;而从PEPCase/RuBPcase的比值看,C4途径的酶在黑农40叶片中表达较高。通过相关分析,我们发现Pn与PSII光化学活性,RuBPCase及C4酶活性密切相关。这些结果还暗示有可能通过检测C4途径酶的表达水平及比例,筛选出具有高产潜力的大豆种质。 二、大豆非叶器官豆荚的光合特性。 通过对大豆非叶器官豆荚光合特性的研究,结果表明大豆豆荚的光合能力在鼓粒期达到最高值。通过叶绿体吸收光谱、荧光动力学和低温荧光等测定技术,我们发现鼓粒期的豆荚对光能的吸收、传递和转化有更高的能力;在鼓粒期不同品种的豆荚色素的含量也较高,从而有利于捕获更多的光能,供光合作用利用。DCIP光还原活力的测定结果表明鼓粒期豆荚也具有较高光合能力。 通过对大豆的初荚期、鼓粒期和衰老期豆荚RuBPCase和四种C4途径酶活性的研究,不仅证明非叶器官中有高活性的C4途径酶和存在有限的C4途径,而且鼓粒期豆荚有较高的碳同化效率。 三、不同大豆叶片和非叶器官光合特性的比较分析。 对三种大豆叶片、豆荚、种皮和子叶的色素含量和Chla/b进行测定,利用光谱技术、荧光技术及RuBPCase活性的测定,分析了大豆不同器官的光合特性。试验结果证明,非叶器官具有与叶器官相似的光合性能。与叶片比较,表明在非叶器官中具有非常高的C4酶活性。有利于补偿叶片开始衰老光合作用衰退的不足,因此非叶器官的这些光合特性有助于增加大豆光合产物的积累。

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在实验室笼养条件下将28只健康成年树鼬按1:2或1:3的雄雌比例配对饲养,并每隔3周进行一次检查,通过一年的试验饲养,研究结果表明,这批实验树鼬共受孕45次,分娩37窝,流产2窝,死产3窝,总产仔147只,成活139只,另有3只母树鼦怀孕待产.每只母树鼩产仔2~3窝,每窝2~5仔,幼仔初生体重为(10.4±1.2)g,40日龄断奶体重为(66.2±15.7)g.该方法树鼩繁殖率和成活率极高,成本相对较低且操作简单,是一种值得参考和借鉴的新方法.

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:从云南西双版纳不同生境下的14 株热带兰菌根中分离到19 株真菌,分别鉴定为9 个属,其中优势 菌为镰孢霉属( Fusarium) 9 株占47. 37 %;组丝核菌属( Phacodium) 3 株占15. 79 %.

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采用腹腔注射和混饲投喂两种方式研究中药甘草(Glycyrrhiza uralensis Fiseh)粗提物对鲫(Carassius auratus)的抗应激和免疫保护功效。将一部分粗提物按0.5%和2%的质量分数制成药饵投喂实验鲫,分别在第14 d、28 d、35 d、42 d、56 d采集血样;将另一部分粗提物用无菌生理盐水按0.5%和2%的浓度配成针剂腹腔注射鲫,分别在第3 d、7 d、14 d、21 d、28 d采集血样。结果显示:投喂实验中药物组和对照组血清皮质醇水平均呈先升后降趋势,除第14 d

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将断面法与地理信息系统(G IS)和全球定位系统(GPS)相结合,通过广泛的野外调查,研究了湖北省梁子湖水生植物物种多样性和群落多样性.结果表明:2002年梁子湖分布有水生植物34科、64属、96种,优势种为菹草、微齿眼子菜、密齿苦草、双角菱、野菱、金鱼藻、穗花狐尾藻、轮叶黑藻和菰;梁子湖的水生植被可划分为19个群丛类型,分布面积最大的为菹草群丛,物种多样性指数最高的是菰群丛;2002年植被覆盖率为37.88%,总生物量为3.037 5×108kg(鲜质量),全湖植被平均单位面积生物量为998.20 g/

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The aerobic degradation of hexachlorobenzene (HCB) by an acclimated microbial community which isolated from a contaminated site and acclimated in our laboratory was investigated. The enriched microbial community was capable of biodegrading HCB when cultivated in minimal salts medium and supplied HCB as the sole carbon source. The efficiencies of microbial community in the degradation of HCB under different pH and temperatures were examined. The phylogenetic analysis for the nearly complete sequences of 16S rDNA demonstrated that the bacteria assemblage in the microbial community was dominated by Azospirillum and Alcaligenes groups.

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Methyl parathion hydrolase (MPH) is an enzyme that catalyzes the degradation of methyl parathion, generating a yellow product with specific absorption at 405 nm. The application of MPH as a new labeling enzyme was illustrated in this study. The key advantages of using MPH as a labeling enzyme are as follows: (1) unlike alkaline phosphatase (AP), horseradish peroxidase (HRP), and glucose oxidase (GOD), MPH is rarely found in animal cells, and it therefore produces less background noise; (2) its active form in solution is the monomer, with a molecular weight of 37 kDa; (3) its turnover number is 114.70 +/- 13.19 s(-1), which is sufficiently high to yield a significant signal for sensitive detection; and (4) its 3D structure is known and its C-terminal that is exposed to the surface can be easily subjected to the construction of genetic engineering monocloning antibody-enzyme fusion for enzyme-linked immunosorbent assay (ELISA). To demonstrate its utility, MPH was ligated to an single-chain variable fragment (scFv), known as A1E, against a white spot syndrome virus (WSSV) with the insertion of a [-(Gly-Ser)(5)-] linker peptide. The resulting fusion protein MPH-A1E possessed both the binding specificity of the scFv segment and the catalytic activity of the MPH segment. When MPH-A1E was used as an ELISA reagent, 25 ng purified WSSV was detected; this was similar to the detection sensitivity obtained using A1E scFv and the HRP/Anti-E Tag Conjugate protocol. The fusion protein also recognized the WSSV in 1 mu L hemolymph from an infected shrimp and differentiated it from a healthy shrimp.

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种子雨是森林植物种群更新的主要方式之一,是森林生态系统自我繁衍和恢复的主要手段。为了解长白山阔叶红松林种子雨的组成及其时空变化,参照BCI 50ha 样地技术规范,在长白山阔叶红松林25ha长期监测样地内设置了150个种子收集器,从2006年5月15日到2007年11月8日,每15天收集掉落于收集器中的果实、种子及其相关附属物等。所收到的样品分别鉴定其种类并分为成熟种实、未成熟种实、花絮、果实或种子碎片及其附属物4类,记录各类别的数量,然后分别烘干称重。 研究期间,共收集到11科12属22种木本植物的种子及其它生殖器官残体,包括成熟种实16种,未成熟种实17种,花序12种,翅2种,果实或种子碎片及其附属物10种。累计收集到种实136664粒,其中成熟种实32358粒,占所有种实总数的23.80%。种实数最多的树种是紫椴(Tilia amurensis),其次为水曲柳(Fraxinus mandshuica),两个树种种实数占总数的89.54%。种实总重量为3320.93g,其中成熟种实总重量为1242.85g,占37.4%。成熟种实中水曲柳和紫椴的重量最大,其次是色木槭(Acer mono),假色槭(A. pseudo-sieboldianum)、糠椴(T. mandshuric)和红松(Pinus koraiensis)。 种子雨数量年际变化明显,2006年种子雨密度为1370.25粒/m2,2007年为249.47粒/m2,差异极显著(P<0.001)。但不同年份种子雨的季节动态趋势一致,均有两个明显的大高峰期和一个小高峰期。不同物种种子雨扩散的时间格局大致可以分为“单峰”和“双峰”两种类型,在时间上体现了不同物种的更新策略。 150个收集器均收到了成熟种实,各收集器中的种实数呈偏态分布,种实数在150-250之间的收集器数量最多,共68个,种实数小于50的收集器有5个,种实数大于250的收集器共37个。样地内成熟种实数量及其空间分布差异明显,收集器中种实数在1000个以上的有3个,最多达1511个,聚集分布于样地的西北角;收集器中种实数最少的只有22个种实。种实重量的空间分布与种实数分布一样存在较明显的空间差异,只是差异性相对偏弱一些,且与种实数量的空间分布不一致。

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本论文对四川蜡瓣花 (Corylopsis willmottiae Rehd. et Wils.)、密花樫木[Dysoxylum densiflorum (Blume) Miq.]、四川溲疏 (Deutzia setchuenensis Franch)及云南豆腐柴 (Premna yunnanensis W. W. Smith)的化学成分进行了研究。通过色谱分离得到44个化合物。主要基于波谱数据鉴定了它们的结构,其中1个为新化合物。 1.从四川蜡瓣花全株的95%乙醇提取物中共分离鉴定了13个化合物,它们是:1-O-(3-O-甲基没食子酸)-岩白菜素(1)、11-O-没食子酰基岩白菜素(2)、 11-O-紫丁香基岩白菜素(3) 、岩白菜素(4)、4-O-没食子酰基岩白菜素(5) 、4,11-O-二没食子酰基岩白菜素 (6)[14]、β-谷甾醇 (7)、acetyl aleuritolic acid (8)、(-)-表没食子儿茶素没食子酸酯(9)、对羟基苯甲酮 (10)、 11-香豆酸酰岩白菜素 (11)[19]、丁香酸 (12)和没食子酸 (13)。其中1为新化合物。 2.从密花樫木根的95%乙醇提取物中共分离纯化了13个化合物,它们是:β-白檀酮(14)、richenone (15)、β-谷甾醇 (7)、cabraleadiol (16)、β-香树脂醇 (17)、龙脑香醇酮 (18)、cabraleadiol monoacetate (19)、cabraleone (20)、3β-hydroxy-5 -pregnen-20-one (21)、3β-hydroxy-5α-pregnan-20-one (22)、cabraleahydroxylactone (23)、川楝子甾醇B (24)、表儿茶素 (25)。 3.从四川溲疏全株95%乙醇提取物中共分离11个化合物,鉴定了其中的9个化合物。它们是:β-谷甾醇 (7)、白桦酯醇(26)、齐墩果酸(27)、hydrangetin (28)、肉桂酸 (29),齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸苷(30)、β-胡萝卜苷 (31)、齐墩果酸-3-O-(β-D-吡喃葡萄糖醛酸-6-正丁酯)(32)、齐墩果酸-3-O-β-D-吡喃葡萄糖醛酸-28-O-β-D-吡喃葡萄糖苷 (33)。 4.从云南豆腐柴95%乙醇提取物中分离得到12个化合物,分别为白桦脂醇 (25)、7-羟基黄烷酮 (34)、松属素 (35)、2’,4’-羟基查儿酮 (36)、高良姜素-3-甲醚 (37) 、高良姜素-3,7-二甲醚 (38)、异甘草素-4-甲醚 (39)、豆蔻明 (40)、乔松酮 (41)、异甘草素 (42)、arjunolic acid (43)、槲皮素3-O-β-D-木糖苷(44)。 5.综述了1976年以来樫木属植物化学成分和活性研究的概况。 Phytochemical investigation on Corylopsis willmottiae, Dysoxylum densiflorum, Deutzia setchuenensis, and Premna yunnanensis, led to the isolation of 44 compounds, 1 of which was new one. 1. One new compound was isolated from 95% ehanolic extrat of the whole plants of C. willmottiae, identified as 11-O-(3-O-methylgalloyl)-bergenin (1). The twelve known compounds isolated were 11-O-galloylbergenin (2), 11-O-syringylbergenin (3), bergenin (4), 4-O-galloylbergenin (5), 4,11-di-O-galloylbergenin (6), β-sitosterol (7), acetyl aleuritolic acid (8), (-)-epigallocatechin 3-O-gallate (9), 1-(4-hydroxyphenyl) ethanone (10), 11-O-coumaroylbergenin (11), syringic acid (12), gallic acid (13). 2. Thirteen compounds were isolated from 95% ethanol extract from the roots of D. densiflorum and identified as β-amyrenone (14), richenone (15), β-sitosterol (7), cabraleadiol (16), β-amyrin (17), hydroxydammarenone-Ⅱ (18), cabraleadiol monoacetate (19), cabraleone (20), 3β-hydroxy-5-pregnen-20-one (21), 3β-hydroxy-5α-pregnan-20-one (22), cabraleahydroxylactone (23), toosendansterol B (24) and (-)-epicatechin (25). 3. Eleven compounds were isolated from ethanol extract of D. Setchuenensis. Nine were identified as β-sitosterol (7), betulin (26), oleanolic acid (27), hydrangetin (28), cinnamic acid (29), oleanolic acid 3-O-β-D-glucuronopyranoside (30), β-daucosterol (31), oleanolic acid 3-O-β-D-glucuronopyranoside-6-O-butyl ester)(32), oleanolic acid 3-O-β-D-glucuronopyranosyl-28-3-O-β-D-glucopyranoside (33). 4. Twelve compounds were isolated from ethanol extract of P. yunnanensis and identified as betulin (26), 7-hydroxyflavanone (34), pinocembrin (35), 2’,4’-dihydroxychalcone (36), galangin 3-methyl ether (37), galangin 3,7-dimethyl ether (38), isoliquiritigenin 4-methyl ether (39), cardamonin (40), pinostrobin (41), isoliquiritigenin (42), arjunolic acid (43), quercetin 3-O-β-D-lyxosopyranoside (44). 5. Chemical constituents and biological activities of the genus Dysoxylum (Meliaceae) were reviewed during 1976-2009.

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土壤是人类赖以生存的自然环境和农业生产的重要资源,目前土壤受到干旱和盐胁迫的危害越来越严重。杨树具有适应性强、生长快和丰产等特性,本论文以青杨组杨树为模式植物,研究杨树对土壤干旱和盐胁迫的生态生理及蛋白质组学反应,研究成果可为我国干旱半干旱地区营造人工林、防止沙漠化提供理论依据,也为恢复与重建盐污染地区退化生态系统提供科学指导。主要研究结果如下: 1 青杨不同种对逐步干旱胁迫的响应差异 将来自喜马拉雅山东缘高海拔的康定杨和低海拔的青杨枝条扦插在温室中,用来检测它们对逐步干旱胁迫的响应。研究结果表明来自不同海拔的杨树对逐步干旱胁迫的适应性反应是不一样的。株高、叶片发育、叶片相对含水量、丙二醛、过氧化氢等指标的显著性变化在青杨中比在康定杨中来得早些,而且随着干旱胁迫程度的增加,这些参数的变化越来越明显,尤其是当青杨受到严重干旱胁迫的时候;而可溶性蛋白、可溶性糖、游离脯氨酸、抗氧化酶活力变化在康定杨中来得早一些。与青杨相比,在干旱胁迫下,康定杨仍能保持较好的植株生长和叶片发育;康定杨也能在逐步干旱条件下积累更多的可溶性蛋白、可溶性糖、游离脯氨酸及抗氧化酶活力,但是在丙二醛和过氧化氢含量方面增加的更少些。而且,我们的研究结果表明高海拔的康定杨有更强的耐干旱能力,杨树对干旱胁迫的适应能力与干旱发生的速度、强度、持续时间及两种杨树的海拔有关。 2 干旱胁迫下青杨不同种的蛋白质组学分析 来自青杨和康定杨雌株的枝条扦插在温室中,用来研究它们对干旱胁迫的蛋白质组学反应。采用TCA-丙酮/酚提取法提取总蛋白,并进行双向电泳分析。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。在青杨中有58 个蛋白在干旱处理后发生显著变化,其中22 个蛋白通过肽指纹图谱成功鉴定。康定杨中有69 个蛋白的表达量发生了显著变化,其中有25 个蛋白通过肽指纹图谱成功鉴定。这些被鉴定的蛋白主要参与了光合作用、氧化还原平衡、信号传导、能量代谢、蛋白质合成等过程。尽管被鉴定的蛋白只占叶片总蛋白的很少一部分,但这些被鉴定的干旱响应蛋白可能对维持植株内部平衡方面有重要作用。 3 青杨的盐胁迫响应 青杨植株分别用 0、50 和100 mM NaCl 溶液进行处理。叶片相对含水量、叶绿素a、b 含量、CO2 同化速率和气孔导度的降低表明叶绿体受到了盐胁迫的影响。过氧化氢、丙二醛含量及电导率的升高表明细胞受到了伤害。可溶性糖、游离脯氨酸含量及抗氧化酶含量的上升增加了植株耐盐胁迫的能力。在每个处理的重复图像中都能检测到1,000 个以上的蛋白点。其中有38 个盐响应蛋白被成功鉴定,有16 个蛋白(点4、10、11、14、15、21、24、26、27、28、33、34、35、36、37 和38)出现在盐胁迫的植株中;3 个蛋白(点10、11 和35)只出现在重度盐胁迫处理中;而1 个蛋白(点1)只出现在对照处理中。2 个蛋白(点1 和2)表达量下降,其余蛋白点表达量都增加。被鉴定的蛋白一部分参与了生理生化反应,而另一部分则在信号传导、蛋白质合成等方面有重要作用。盐胁迫下的生理生化变化及蛋白质组学的联合研究有利于青杨对盐胁迫的适应性分析。 Soil is the indispensable environment for human survival and important resource for agriculture development. Nowadays soil is threatened by drought stress and salt stress. Poplars (Populus spp.) possess some characters such as strong acclimilation, fast growth and great production of biomass. In this study, different species of Populus section Tacamahaca spach were used as model plants to investigate the ecophysiological and proteomic responses to drought stress and salt stress. Our results can provide theoretical evidence for the afforestation and prevention of desertification in the arid and semi-arid areas, and also can supply scientific direction for the reconstruction and rehalibitation of ecosystems contaminated by salinity. The results are as follows: 1 Adaptive responses to progressive drought stress in two contrasting poplar species originating from different altitudes Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehd., originating from high and low altitudes in the eastern Himalaya, respectively, were examined during one growing season in a greenhouse to determine the effects of progressive drought stress. The results manifested that the adaptive responses to progressive drought stress were different in these two species from different altitudes. Significant changes in height increment, leaf development, relative water content (RWC), malondialdehyde (MDA) and hydrogen peroxide (H2O2) appeared earlier in P. cathayana than in P. kangdingensis, whereas changes in soluble protein, soluble sugar, free proline and antioxidant enzymes appeared earlier in P. kangdingensis. In addition, changes in these parameters became more and more significant when the drought stress progressed, especially under severe drought stress in P. cathayana. Compared with P. cathayana, P. kangdingensis was able to maintain a superior height increase and leaf development under drought stress. Also, P. kangdingensis possessed greater increments in soluble protein, soluble sugar, free proline and antioxidant enzymes, but lower increments in MDA and H2O2 than did P. cathayana when the cuttings were exposed to progressive drought stress. Our results suggest that P. kangdingensis originating from the high altitude has a better drought tolerance than does P. cathayana originating from the low altitude. Furthermore, this study manifested that acclimation to drought stress are related the rapidity, severity, duration of the drought event and the altitude of two contrasting species. 2 Proteomic responses to drought stress in two contrasting poplar species originating from different altitudes The cuttings from a female clone of P. kangdingensis and P. cathayana were used to determine proteomic response to drought stress, respectively. Total proteins of the leaves were extracted by a combination of TCA-acetone and phenol, and separated by two-dimensional gel electrophoresis. More than 1,000 protein spots were reproducibly detected on each gel. 58 differentially expressed spots were detected under drought stress in P. cathayana and 22 drought-responsive proteins were identified by peptide mass fingerprint. 69 differentially expressed spots were detected under drought stress in P. kangdingensiss and 25 drought-responsive proteins were identified by peptide mass fingerprint. The identified proteins are involved in several processes, i.e., signal transduction, protein processing, redox homeostasis, CO2 fixation and energy metabolism. Although the proteins identified in this investigation represent only a very small part of the poplar leaf proteins, some of the novel drought-responsive proteins identified here may be involved in the establishment of homeostasis in response to drought stress in the woody plants. 3 Responses to salt stress in P. cathayana Cuttings from a female clone of P. cathayana were treated by Hoagland’s solution: 0, 50, 100 mM NaCl, respectively. Salinity significantly decreased the relative water content of leaves, the contents of chlorophyll a and chlorophyll b, CO2 assimilation rate (A) and stomatal conductance (gs) in both salt stress treatments,which suggested the chloroplast was affected by salt stress. The observed increases of H2O2 and malondialdehyde contents and electrolyte leakage suggested that salinity caused cellular damage, whereas the increases in compatible solutes and in the activities of antioxidant enzymes enhanced the salt tolerance. More than 1,000 protein spots were reproducibly detected on each gel, and 38 salt-responsive proteins were successfully identified by peptide mass fingerprint (PMF). 16 spots (spot 4, 10, 11, 14, 15, 21, 24, 26, 27, 28, 33, 34, 35, 36, 37 and 38) absent in the control sample were induced by the salt treatment, and three spots (spot 10,11 and 35) were present only in the severely salt-stressed treatment. The %vol of the differentially expressed proteins generally increased with progressing salt stress, except for the decreased %vol of two proteins (spot 1 and 2) under salt stress and the presence of spot 1 only in the control sample. Some of the novel salt-responsive proteins identified here may be involved in physiological, biochemical response to salt stress in P. cathayana, the other identified proteins play a role in numerous cellular functions, including signal transduction and protein processing. An integrated physiological, biochemical and proteomic approach was used here to systematically investigate salt acclimation in poplar.