959 resultados para Aisberg-2-2006-1
Resumo:
辐射传输研究是贯穿森林生态系统的纽带,太阳辐射为植物的生长发育提供光合能量、适宜的环境温度以及发育信息。一方面,气候变化使到达地面辐射能的质和量发生变化,影响到植被的生长发育,改变森林的结构,而森林结构的变化又会影响林冠内辐射能的分配和质量,这些变化会进一步影响到林下土壤温度,改变森林根系活性以及土壤营养转化的效率;连锁反应的结果有可能会使森林生态系统的生产力发生变化,改变碳素和氮素源库的调节方向,从而反馈影响地球气候系统。另一方面,人类作为生态系统的成员,必然需要森林生态系统为其提供更多的原材料和更好的生态服务功能,如何实现这些目标,就需要人类适度调整干预方式和频度,达到预期的目的。本文在建立适合于川西亚高山森林的叶面积测量技术、光照辐射模型和土壤温度变化模型的基础上,对川西亚高山地带森林生态系统的辐射传输特征进行了分析,并从森林结构的角度探讨了林分内的辐射分布以及对土壤温度的影响。主要成果如下: 1. 提出了一种照相法测量叶面积的方法。通过对摆放在平面上的叶片照相,利用投影变化,把非正射图像转化为正射图像,然后经过计算机图像处理得到每一片叶片的面积、周长、长度、宽度等信息。这种方法可使用户以任意方向和距离拍摄处于平面上的叶片,能同时处理大量的叶片,适于野外离体或活体叶片测量。叶片面积分辨率可调,分辨率可以与常用的激光叶面积仪相近甚至更高,而且叶片图像可以存档查询。 2. 提出一种模拟林内光照变化的模型。利用林冠半球照片,记录视点以上半球内的林冠构件空间分布,作为林冠子模型;天空辐射子模型采用国际照明委员会(CIE)的标准晴天和阴天以及插值模型。该模型能够模拟林下某一位点处的实时光斑变化。 3. 提出一种土壤温度变化模型。把土壤视为具有容量和阻力性质的结构,利用电阻和电容器件构建土壤能量分布模型。外界太阳辐射能经过植被以及其它一些能量分配器后进入土壤,其中有一部分转化为土壤势能,即土壤温度。土壤温度的变化类似于电池的充放电过程。在已知模型参数的情况下,可以从太阳辐射计算土壤温度的变化。在模型参数未知的情况下,通过输入和输出值推算模型的参数,而模型参数中的时间常数与土壤组成和含水量有关,这样就可以知道土壤水分的变化情况。 4. 从王朗亚高山森林典型样地林分结构的测量获得林地三维结构图、树冠形态、叶面积密度等参数,这些参数输入到Brunner (1998)开发的tRAYci 模型中计算出一段时间内林分任意位置处的光照值。与林下辐射计测量值以及半球照片计算结果的比较,该模型基本上能够满足对林分光环境了解的要求。 5. 从川西亚高山森林生产力的角度,探讨了森林生产力研究的方法以及川西地区的研究历史和成果,发现了其中的一些规律和问题,特别是在叶面积测量上,还没有使用标准的叶面积指数定义。综合来看,川西地区针叶林叶面积指数(单位土地面积上植物冠层总叶面积的一半) 应在4-5 之间。降雨丰富的华西雨屏带是川西地区森林生产力最高的地区,而向西北森林生产力逐渐降低。川西地区云冷杉林森林生产力平均约为600 gDM m-2 a-1,但是根据辐射能计算的潜在生产力则达到1800 gDM m-2 a-1。实际与潜在森林生产力的巨大差异说明其它因子对生产力的影响。 6. 王朗亚高山3 个典型森林林分中,白桦林样地(BF) 林下草本以糙野青茅、牛至、紫菀等喜阳性物种为主,林下透光度较高;冷杉林样地(FF) 林下透光度最低,以喜阴性物种水金凤、蟹甲草、囊瓣芹等为主;而云杉林样地(SF)林分林龄最大,林下透光度介于冷杉林和白桦林之间,草本层仍然以喜阴性物种东方草莓、紫花碎米芥、酢浆草等为主。冷杉林和云杉林的灌木层也很丰富,卫矛属、五加属、茶藨子属、忍冬属植物很丰富,而在白桦林则以栒摘要子属、榛子属、鹅耳枥属等植物为主。藓类植物在云杉林中最丰富,并且形成毯状层,其它两个林分则很稀少。3 个样地林分结构与林下光环境有很强的相关性,从光环境特征可以在一定程度上推测林分的结构。各样地单纯从乔木层材积推算的NPP 排列顺序为BF>FF>SF,与林下辐射透射率和林分年龄的顺序相同,暗示辐射对群落演替过程的驱动作用。 7. 用半球照相法测得BF、FF 和SF 3 个样地的有效叶面积指数以SF 样地最高,BF 最低。如果考虑针叶树叶片在小枝上的丛聚分布,利用北方针叶林的数值进行校正,则SF 样地LAI 显著增加(达到89%),其它样地的LAI 基本不变甚至有所下降。校正后的数值与文献中地面测量的结果较相近,说明在使用半球照相法测量川西亚高山针叶林LAI 时必须加以校正。 8. 在3 个样地中,白桦、岷江冷杉和方枝柏种群为丛聚分布,紫果云杉在FF和SF 样地中基本上为随机分布。3 个物种出现丛聚分布的最短距离约为2m,在最短距离以内则为随机分布。最短距离可能与树冠大小有关,种子传播特征以及对光照的需求状况可能是造成这种分布格局类型的原因。 Radiative transfer plays a key role in forest ecosystems. Solar radiation providesenergy for photosynthesis, appropriate ambient temperature and development informationfor plants. However, quality and quantity of radiation reaching land surface are affected byweather and subsequently influence the growth and development of plants, which in turnchanges the budget of radiation in forest. Soil temperature changes with the variation ofradiation under forest canopy and influences the activity of roots and rate of nutrientturnover. Thus, any changes of radiation will induce chain reactions in the entireecosystem and display in the value of net primary productivity which will possibly shiftthe relationship between carbon source and sink at local or regional scale and feed back tothe global climate system. On the other hand, as a component of ecosystems, humanbeings of course need to demand more materials and better service from ecosystems. Forthese purpose, man must adapt their pattern and frequency of interference to ecosystems.This paper aims to research on the canopy structure, the radiation distribution and theirinfluence on soil temperature from the process of radiative transfer in subalpine forestecosystem of western Sichuan. The main results are: 1 Present a new photogrammetric method for leaf area. The main idea is to convertnon-vertically taken images of planar leaves to orthoimages through projectivetransformation. The resultant images are used to get leaf morphological parametersthrough image processing. This method enables users to take photos at almost anyorientation and distance if only the leaves are placed on same plane, and to processlarge quantity of leaves in a short time, which is suitable for field measurement. Theresolution of leaf area is adjustable to fit for special requirement. 2 A model using hemispherical photos combining with solar tracks and radiation courseis provided to simulate light variation in forest. The hemispherical photos of canopyrecord the real spatial distribution of each element of plants viewed from a point. Skyradiance is simulated with CIE standard clear sky or cloudy sky model. This modelcan be used to simulate real time light variation under canopy. 3 Present a soil temperature model. Soil could be regarded as a body of resistor andcapacitor. Some of the budget of solar radiation in soil body is transformed into soilpotential energy, the soil temperature. Variation of soil temperature is driven by solarradiation, vegetation, soil properties, etc. This model has two parameters, one of whichis time constant and is related to soil water content. The inversed model can be used tosimulate the variation of soil water. 4 By using model tRAYci developed by Brunner (1998), the 3-D distribution of light inthree subalpine forest stands of Wanglang Nature Reserve has been simulated andvalidated with value of radiometers in these stands. This model can basically satisfythe need for understanding light regimes of these stands. 5 Present some principles and questions of NPP (net primary of productivity) researchesin western Sichuan. The standard leaf area index (LAI) defined by Chen and Black(1997) has not been used in this region. Total leaf area and projected leaf area indexare still used in NPP researches which may differ around 1-fold in magnitude. Thestandard LAI which is a half of total leaf area above unit land area should be between4 and 5 for typical subalpine coniferous forest of western Sichuan concluded fromliteratures. The maximum forest NPP occurs in West China rain belt and decreasesnorthwestwards. Average NPP of spruce-fir forest in western Sichuan is about600gDM m-2 a-1, which is below the potential NPP of 1800gDM m-2 a-1 based onmeasured radiation in this region. The significant difference between potential and realNPP suggests that other factors influence the growth of stands. 6 In the three subalpine forest stands of Wanglang Nature Reserve, herbage layer ofAbstractbirch stand (BF) with age of 40 is dominated by heliophytes of Deyeuxia scabrescens,Origanum vulgare, Aster tongoloa etc.. However, both of the other two stands aredominated by shade tolerent species, such as Impatiens noli-tangere, Impatiensdicentra, Cacalia deltophylla and Pternopetalum tanakae etc. in fir stand (FF) withage of 180 and Fragaria orientalis, Cardamine tangutorum and Oxalis corniculata etc.in spruce stand (SF) with age of 330. Shrub species in the latter two stands arerelatively rich, typical dominant genera being Euonymus, Acanthopanax, Ribes andLonicera. Birch stand has relatively sparse shrubs dominated by genera of Cotoneaster,Corylus and Carpinus. Mosses are significant only in spruce stand. The canopystructure controls the light regime of stand, which influence the composition of herblayers beneath the canopy. This light regime-community structure relationship can beused to infer the herb community from canopy structure. The NPP derived from timbervolume of arbor layer of the three stands decreases from BF to SF, which is in thesame order of transmitted total radiation under canopy and age of these stands,suggesting the driving effect of radiation in the succession of community. 7 The highest effective LAI of the three stands obtained by hemispherical photos is inplot SF and lowest in plot BF. After rectification of the clumping effect of leaves onshoot, the real LAI in plot SF increases significantly (89%) and approximate to theaverage LAI of coniferous forest in western Sichuan. Therefore, the LAI obtainedfrom hemispherical photos needs rectification for clumping effect. 8 Spatial distribution pattern for Betula platyphylla, Abies faxoniana and Sabinasaltuaria is clumpy, but Picea purpurea almost random in plot FF and SF. The shortestdistance for clumpy distribution for Betula platyphylla and Sabina saltuaria is 1.5m,and 2m for Abies faxoniana. And random pattern for these trees is exhibited within thisrange which almost coincides with the diameter of crown. Seed dispersalcharacteristics and light requirement may be the reason for different spatial pattern.
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小麦加工品质改良已成为我国小麦育种的主要目标之一。特别是我国加入WTO以后,对小麦产品的质量提出了更高的要求,小麦品质改良的任务将更加艰巨和重要,小麦胚乳蛋白是影响小麦加工品质性状的重要因素。因此,深入了解小麦胚乳蛋白对加工品质性状的影响及其分子基础,为品质改良提供理论依据和科学指导,对加速我国小麦品质育种和优质小麦生产具有重要意义。本研究选用在麦谷蛋白5个基因位点(Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3)上均含不同等位基因的小麦品种99G45和京771及Pm97034和京771杂交F9代共164个麦谷蛋白纯合系,及228个中国推广普通小麦品种和高代育成品系为试材,研究了麦谷蛋白Glu-1和Glu-3位点基因等位变异对籽粒蛋白、湿面筋含量、Zeleny沉降值和SDS沉降值间的关系;本研究还利用小麦A、B和D基因组中低分子量麦谷蛋白亚基(LMW-GS)基因特异引物,通过PCR方法克隆了1个Glu-A3位点和3个Glu-B3位点LMW-GS基因片段,在此基础上分析了不同等位基因对品质造成差异的分子基础;另外,本研究对中国近年推广的部分品种和育成的高代品系资源的多样性进行了分析。现将主要研究结果简述如下: 1. 对来自三个麦区的148份材料的醇溶蛋白组成进行了分析,结果表明,各麦区醇溶蛋白模式具有较大差异。在ω区,A7、B、E、F、G、J、P、Q、S和U仅存在于西南秋播麦区;A3、M、N、R、W和X仅存在于黄淮特种麦区;K仅存在于北方冬麦区;A6是北方冬麦区出现频率最高的带型模式,而西南秋播麦区中D出现的频率最高。ω-区的E、H和M几种模式是以前国内外未曾报道的。且初步确定,这些模式对品质性状具有正效应。至于γ区,A、B、D、E和F在各区均有出现,其中B和E在各区出现的频率都很高,在26.1-39.6%之间。相反,H 仅出现在黄淮特种麦区,J仅限于西南秋播麦区。对于β-区醇溶蛋白,B型模式在所有区中都相当高,而模式A仅存在于第三区.对于α-区,模式A在Ⅲ区而模式D在Ⅱ区出现的频率很高。1BL.1RS易位系在中国小麦品种中出现频率高达41.2%,在I, II和Ⅲ麦区的出现频率分别为 45.5、43.5和35.2%。各生态区模式的差异可能是品种适应不同生态条件和人为选择的结果,但这有待进一步证明。由于醇溶蛋白位点(Gli-1)与LMW-GS位点(Glu-3)紧密连锁,本结果可为下面确定普通小麦LMW-GS等位基因变异所用。 2. 利用Gli-1与Glu-3的紧密连锁,以228个小麦品种/系为材料,首次对中国小麦品种麦谷蛋白亚基的6个位点进行综合分析,研究小麦籽粒蛋白与品质性状间的关系,结果表明6个高分子量(HMW)和低分子量(LMW)麦谷蛋白位点对蛋白质含量的效应大小为,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3;对GMP含量的效应大小为, Glu-A3>Glu-B3>Glu-D1> Glu-B1>Glu-A1>Glu-D3;对湿面筋含量的效应大小为, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1;对Zeleny沉降值的效应大小为, Glu-A1> Glu-B3>Glu-D3>Glu-D1>Glu-B1>Glu-A3;对SDS沉降值的效应大小为, Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1。对蛋白含量而言,各位点的最佳组合方式为1、17+18、5+10、Glu-A3e、Glu-B3g、Glu-D3b;对湿面筋含量而言,各位点的最佳组合方式为1、6+8、5+10、Glu-A3d、Glu-B3c、Glu-D3b;对Zeleny沉降值而言,各位点的最佳组合方式为N、17+18、5+10、Glu-A3d、Glu-B3d、Glu-D3b;对SDS沉降值而言,各位点的最佳组合方式为1、7+8、2.2+12、Glu-A3b、Glu-B3g、Glu-D3b。另外,分析了稀有亚基对5+12与2.2+12与品质性状的关系,认为5+12对品质有负效应,2.2+12对品质有正效应。在品质育种时,应对优异组合或优异亚基加以利用。 3. 首次利用重组自交系(RILs)为材料,研究麦谷蛋白亚基表达量与品质性状的关系,通过对重组自交系中各HMW-GS表达量的分析,认为,就单个亚基的表达量而言,7亚基最高;其次为2亚基、5亚基、12亚基和10亚基;亚基9和1的表达量最小;N亚基不表达。对成对出现的亚基对而言,x型和y型亚基的总表达量2+12>5+10>7+9>17+18。就单个亚基与品质性状的关系而言,仅有10亚基的表达量与蛋白含量的相关性达5%的显著水平,2亚基的表达量与湿面筋含量呈负相关,显著水平也达5%,其余单个亚基对品质性状均无显著影响;就x型/y型亚基的比例来看,2/12和5/10对湿面筋含量都有显著的负效应;对某一位点等位基因控制的亚基表达总量来看,2+12对SDS沉降值有显著负效应。另外,本研究得出:2+12的亚基对的负效应主要体现在2亚基上,且在同一位点上,x型亚基的表达量大于y型。所以推导稀有亚基组合2+10很可能也是劣质亚基。 4. 以 Glu-A1、Glu-B1、Glu-D1、Glu-B3和Glu-D3作为5个因素对99G45/京771和Pm97034/京771杂交后代的蛋白质含量和SDS沉降值进行多因素方差分析。结果表明,Glu-A1和Glu-D3对蛋白含量的加性效应达5%显著水平;Glu-D1 * Glu-D3对蛋白质含量的互作效应也达5%显著水平;其余位点的加性和互作效应对蛋白质含量的影响均不显著。对SDS 沉降值而言,Glu-D1的加性效应最大,贡献率为4.2 % ,达1 %显著水平,其次是Glu-B1位点,贡献率为3.3% ,达5%显著水平。其余位点对SDS 沉降值的加性和互作效应均未达5%显著水平。总体而言, 各位点对蛋白含量的效应大小为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3;对SDS沉降值的效应大小为Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。Glu-D1和Glu-D3位点上等位基因变异对蛋白含量有显著或极显著影响,含Glu-D1d和Glu-D3 GD、Glu-D3 JD基因的株系分别比含Glu-D1a和Glu-D3 PD基因的株系有较高的蛋白含量;在该遗传背景下,麦谷蛋白各基因位点对蛋白含量的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9>17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。对SDS沉降值的效应大小依次排列为:Glu-A1位点1>N;Glu-B1位点7+9=17+18>14+15;Glu-D1位点5+10>2+12;Glu-B3位点GB>JB>PB;Glu-D3位点GB>JB>PB。所以,对蛋白含量和SDS沉降值均较好的组合为1,7+9,5+10,GB,GD。 5. 因为GB和PB对品质的效应有显著差异,选取LMW-GS位点特异扩增引物对京771、99G45和Pm97034的Glu-B3位点进行扩增,结果得到三个不一样的扩增片段(Genebank号为DQ539657-DQ539659),得到的基因片段与Genebank中已报道的同类序列高度同源。通过克隆片段组成的分析,发现对Pm97034的序列较京771和99G45段少一个7氨基酸的重复单元,这可能是它较另外两个片段对面筋强度影响小的主要原因;另外,在99G45的序列中,124位处出现L(亮氨酸)代替P(脯氨酸),158位处出现了T(苏氨酸)代换M(蛋氨酸),这可能是99G45Glu-B3位点序列对SDS沉降值的效应显著优于Pm97034的原因。 6.通过对RILs各位点同普通小麦品种(系)各位点与品质关系的比较,发现对SDS沉降值的效应,各位点在不同研究材料中是不同的,普通小麦中:Glu-B3>Glu-A1=Glu-D1=Glu-A3>Glu-D3>Glu-B1,RILs中:Glu-D1>Glu-B1> Glu-D3>Glu-A1> Glu-B3。利用重组自交系材料(完全排除了1BL/1RS易位干扰)所得到的结果与Gupta and MacRitchie (1994)所得结论一致。进一步证实了1BL/1RS易位对小麦品质的重要影响。对蛋白含量而言,普通小麦品种(系)中,Glu-D1>Glu-B3>Glu-A1=Glu-B1> Glu-A3=Glu-D3,RILs中,Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3,和对SDS沉降值的效应一样,推断在非1BL/1RS易位的情况下,各位点对其效应应为Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3。 对同一位点的等位基因而言,普通小麦和重组自交系中Glu-A1和Glu-D1上的等位基因对品质性状的贡献是一致的,但Glu-B1上的等位基因对SDS沉降值的贡献发生了变化,普通小麦中17+18>7+9,RILs中7+9>17+18,这可能也是1BL/1RS造成的。 Baking quality improved is one of the main object of wheat bread in China. The overall objective of the present studies was to increase the understanding about protein quality in wheat, i.e. to make it possible to improve the production of wheat with desired quality for different end-uses. With the analysis of gluten protein in RILs, 99G45/Jing 771 and Pm97034/Jing, and 228 wheat cultivars or lines in China, the correlations between glutenin compositions and protein content, glutenin macropolymer(GMP), wet gluten content, Zeleny sedimentation value and SDS sedimentation value contentand breadmaking quality were studied. Also a rapid and efficient detection method of geneticpolymorphism at Glu-B3 loci in wheat was established using polymerase chain reaction(PCR).The results obtained were as follows: 1. Cultivated Chinese wheat germplasm has been a valuable genetic resource in international plant breeding. Patterns of gliadin among cultivated Chinese accessions are unknown, despite the proven value and potential novelty. The objective of this work was to analyse the diversity within improved Chinese wheat germplasm. The electrophoretic banding patterns of gliadin in common wheat cultivars and advanced lines were determined by acid-polyacrylamide gel electrophoresis. For 148 leading commercial cultivars and promising advanced lines used in our study, 48 patterns were identified, 29 corresponding to ω-gliadin, 9 to γ-gliadin, 5 to β-gliadin and 5 to α-gliadin. The most frequent patterns were A6 in ω; B in γ; B in β and A in the region of α. 116 band types appeared in the148 samples: 94 accessions had unique gliadin types, and 22 gliadin types while not unique were found in 54 accessions. The gliadin patterns of Chinese wheat cultivars and lines greatly differed from the patterns of wheat lines from other countries. Three patterns, E, J, H, M, N and O in the ω-zone had not previously been reported. Three wheat zones,the Northern Winter Wheat Region, the Yellow and Huai Valley River valleys Winter Wheat Region and the Southwestern Winter Wheat Region,in China showed different frequencies in their gliadin patterns. This information can be used to monitor genetic diversity with Chinese wheat germplasm. 2. To analyse the relationship between the loci and characteristics quality, we utilized the 228 cultivars/lines. The results showed that : For protein content, Glu-D1 >Glu-B3>Glu-A1=Glu-B1>Glu-A3=Glu-D3. For GMP content, Glu-A3>Glu-B3 >Glu-D1>Glu-B1>Glu-A1>Glu-D3. For wet gluten content, Glu-B1>Glu-B3= Glu-D3>Glu-A3>Glu-A1>Glu-D1. For Zeleny sedimentation value, Glu-A1>Glu-B3> Glu-D3>Glu-D1>Glu-B1>Glu-A3, For SDS sedimentation value, Glu-B3>Glu-A1= Glu-D1= lu-A3>Glu-D3>Glu-B1。For protein content, the best combination of 6 loci is (1,17+18,5+10,Glu-A3e, Glu-B3g,Glu-D3b). For wet gluten content, the best combination of 6 loci is (1,6+8,5+10,Glu-A3d,Glu-B3c,Glu-D3b). For Zeleny sedimentation value, the best combination of 6 loci is (N,17+18,5+10,Glu-A3d, Glu-B3d, Glu-D3b). For SDS sedimentation value, the best combination of 6 loci is(7+8,2.2+12,Glu-A3b, Glu-B3g,Glu-D3b)。Additional, we analysed the relationship between the subunits 5+12 and 2.2+12, think that 5+12 was negative for quality, 2.2+12 is postive for quality. It should be effective utilized. 3. It’s the first time to utilize RILs to study the relationship between subunits expression quantity and characteristics quality. The results showed that: For single subunit, the expression quantity of 7 is the highest. Then the 2, 5, 12 and 10. The expression of subunit 9 and 1 is the lowest. Subunit N is not expressed. For subunits, the expression quantity of x type and y type are 2+12>5+10>7+9>17+18. The significant relation of 5% only showed between the expression quantity of subunit 10 and protein content. The relationship between expression quantity of others and characteristic quality was not significant. For x type/ytype, 2/12 and 5/10 is negative relation insignificant level. For the subunit(s) in a loci, Only 2+12 effect SDS sedimentation value negative in significant level. 4. With RILs 99G45/Jing 771 and Pm97034/Jing 771, we found that: The effective of Glu-A1, Glu-D3 and Glu-D1 * Glu-D3 for protein content is significant at 5% level. The effect of other loci for protein wre not significant. For SDS sedimentation value, the effect of Glu-D1is the highest, which contribution is 4.2 % .Then the Glu-B1, contribution is 3.3%. The effect of other loci for SDS sedimentationvalue were not significant. In total, for protein content: Glu-D3 > Glu-A1 > Glu-D1>Glu-B1>Glu-B3; for SDS sedimentationvalue: Glu-D1>Glu-B1> Glu-D3>Glu-A1>Glu-B3. The effect of alleles in Glu-D1 and Glu-D3 loci are significant at 1% or 5%. In Glu-A1, 1>N; Glu-B1, 7+9>17+18>14+15; Glu-D, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. For SDS sedimentation, Glu-A1, 1>N; Glu-B1, 7+9=17+18>14+15; Glu-D1, 5+10>2+12; Glu-B3, GB>JB>PB; Glu-D3, GB>JB>PB. The best combinations for SDS sedimentation value is 1,7+9,5+10,GB,GD. 5. Because of the difference of GB and PB for SDS sedimentation value, we selected the specific primer for LMW-GS loci to amplified the Glu-B3 of Jing771, 99G45and Pm97034. We got 3 amplify fragment (Gene Bank accession number are DQ539657-DQ539659). We found that the fragment of Pm97034 were deleted a repetitive 7 amino acid domain, which is perhaps the reason effect the gluten strength. Furthermore, in the position 124 of sequence 99G45, L has been replaced with P. Position 158, T replaced M, which may be the reason why the Glu-B3 locus of 99G45 is prefer to Pm97034 when refer to SDS sedimentation value. 6. Comparing the results of RILs and common wheat, we found that perhaps just the1BL/1RS made the difference of loci in different accession.
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14MeV中子可以引起重核奇异的(n,2p)反应。中能较轻的重离子轰击重核,可以产生多核子转移反应,并以此为基础形成了我们合成和研究重丰中子新核素的一条物理思想和生成、分离鉴别技术路线。介绍了化学分离和X-γ符合方法(元素分离方法);先后合成了一些如185Hf、186Hf、237Th、238Th、239Pa、175Er和197Os等重丰中子新核素,并测定它们的半衰期分别为3.5min、2.6min、5.0min、9.4min、106min、2.8min和1.2min;还观测了它们其他的衰变性质,如新γ射线和衰变纲图等。
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利用能量为170MeV的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研究了188Tl的高自旋态能级结构.依据实验结果建立了188Tl基于πh9/2(?)vi13/2组态的转动带.根据双奇Tl核能级结构的相似性,指定了188Tlπh9/2(?)vi13/2扁椭球转动带的自旋值.结果表明在188Tl中,πh9/2(?)vi13/2扁椭球转动带在低自旋区具有旋称反转性质.利用包含了质子-中子剩余相互作用的准粒子-转子模型,定性地解释了πh9/2(?)vi13/2扁椭球转动带的低自旋区旋称反转现象.
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The multi-configuration Dirac Fock (MCDF) method is implemented to study doubly excited 2s2p P-1,3(1) resonances of the helium atom and the interference between photoionization and photo excitation autoionization processes. In order to reproduce the total photoionization sprectra, the excited energies from the ground 1s(2) S-1(0) state to the doubly excited 2s2p P-1,3(1) states and the relevant Auger decay rates and widths are calculated in detail. Further more, the interference profile determined by the so-called Fano parameters q and rho(2) is also reproduced. Good agreement is found between the present results and other available theoretical and experimental results. This indeed shows a promising way to investigate the Fano resonances in photoionization of atoms within the MCDF scheme, although there are some discrepancies in the present calculations of the 2s2p P-3(1) state.
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The ovaries of Kun-Ming strain mice (3 weeks) were irradiated with different doses of C-12(6+) ion or Co-60 gamma-ray. Chromosomal aberrations were analyzed in metaphase II oocytes at 7 weeks after irradiation. The relative biological effectiveness (RBE) of C C-12(6+) ion was calculated with respect to Co-60 gamma-ray for the induction of chromosornal aberrations. The C-12(6+) ion and Co-60 gamma-ray dose-response relationships for chromosomal aberrations were plotted by linear quadratic models. The data showed that there was a dose-related increase in frequency of chromosomal aberrations in all the treated groups compared to controls. The RBE values for C-12(6+) ions relative to (CO)-C-60 gamma-rays were 2.49, 2.29, 1.57, 1.42 or 1.32 for the doses of 0.5, 1.0, 2.07 4.0 or 6.0 Gy, respectively. Moreover, a different distribution of the various types of aberrations has been found for C-12(6+) ion and Co-60 gamma-ray irradiations. The dose-response relationships for C-12(6+) ion and (CO)-C-60 gamma-ray exhibited positive correlations. The results from the present study may be helpful for assessing genetic damage following exposure of immature oocytes to ionizing radiation.
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On the basis of previous work, the hyperfine-induced 3s3p P-3(2) -> 3s(2) S-1(0) E1 transition probabilities of Mg-like ions were further calculated using the GRASP2K package based on the multiconfiguration Dirac-Hartree-Fock method. The contribution to the lifetime of the P-3(2) level from the 3s3p P-3(2) -> 3s(2) S-1(0) hyperfine-induced E1, 3s3p P-3(2) -> 3s3p P-3(1) M1, 3s3p P-3(2) -> 3s(2) S-1(0) M2 and 3s3p P-3(2) -> 3s3p P-3(0,1) E2 transition was discussed in detail. It was found that hyperfine interaction has an obvious effect on the lifetime at the beginning of the Mg-like isoelectronic sequence.
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目的:建立重离子束辐照结合植物组织培养技术进行植物诱变的新方法,使用该方法率先开展植物组织细胞的传能线密度(LET)生物学效应的研究,尝试重离子束辐照结合农杆菌转染及质粒微注射法转基因操作。 材料与方法:采用兰州重离子研究装置(HIRFL)加速的碳离子束辐照非洲紫罗兰、丽格海棠、新几内亚凤仙以及紫花苜蓿的外植体,测定形态学指标,计算不同外植体的相对生物学效应(RBE)。以非洲紫罗兰叶片外植体为对象研究RBE随LET的变化关系。使用氖离子束辐照烟草叶片外植体结合农杆菌转染方法进行赤霉素4(GA4)基因转染实验;使用碳离子束辐照苜蓿愈伤组织结合质粒微注射方法进行β-葡萄糖苷酸酶(GUS)基因转染实验。 结果: 1. 不同剂量的936MeV的碳离子束和8MV的X射线辐照三种花卉及一种牧草的外植体后,基于存活率的RBE值分别为2.3、1.6、2.1和4.0; 2. LET值在31~151keV/μm区间的碳离子束辐照非洲紫罗兰叶片外植体。基于鲜重增殖(FWI)的RBE值随LET的增加而增加,151keV/μm时达到最高值6.7; 3. 烟草离体叶片外植体经过5Gy的1600MeV氖离子束辐照后进行农杆菌转基因操作,最终获得转染率为3.9%,单纯农杆菌转基因的转染效率为3.2%; 4. 20Gy的936MeV的碳离子束辐照苜蓿愈伤组织后结合组织表面pBI121质粒溶液微量注射处理后,获得GUS基因瞬间表达效率高达84.6%。 结论: 1. 不同花卉植物组织培养用外植体的辐照敏感性不同,本研究发现丽格海棠的辐射敏感性最高,其次是新几内亚凤仙,非洲紫罗兰的最不敏感; 2. 不同花卉植物外植体经离子束辐照诱变处理后,得到的再生植株突变类型不尽相同,主要包括叶的突变和茎的突变; 3. RBE的随LET的增大而增加可以归因于离子在生物体中能量沉积的增加,研究发现各生物学终止点受到损伤或者抑制的程度基本上是随着LET的增大而增大; 4. 通过离子束辐照结合植物组织培养方法最终获得了非洲紫罗兰叶绿素缺失突变体,该突变体通过植物组织培养技术能够稳定遗传; 5. 中能氖离子束辐照能够略微提高烟草农杆菌转基因的转化效率,辐照能够使再生植株花期提前; 6. 中能碳离子束辐照结合苜蓿愈伤组织表面微量注射质粒溶液法进行转基因操作能获得更高的基因转染效率
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基于28个20mx90m样地的调查数据,利用Lotka-Volterra模型,本文分析了长白山北坡阔叶红松(Pinuskoraiensis)林和云冷杉林(也叫暗针叶林)群落交错区优势树种之间的竞争及动态。结果显示:在自然条件下,群落将向两个方向分化,一是以云杉(PiceajezoensisandP.koraiensis)和冷杉(Abiesnephrolepis)为优势的群落,并在达到平衡时冷杉占绝对优势(相对优势度的77.1%):另一种是以红松或云冷杉和阔叶树占绝对优势的针阔混交林,并在达到平衡时,阔叶树在阔叶红松林中占相对优势度的50%,在云冷杉一阔叶林类型中占66%。同时,本研究说明:(1)阔叶红松林和云冷杉林都是长白山气候顶极群落:(2)交错区具有过渡性质:(3)森林群落的分化结果说明演替的方向受局部生境的影响。图1表3参24。
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利用LI-6400CO2分析系统测定了长白山红松针阔叶混交林生态系统土壤呼吸、乔木和灌木树干和枝条的呼吸、植物叶片光合与呼吸.同步监测森林小气候气象因子,建立土壤、树干、叶片与气象因子间的模型.根据红松针阔叶混交林植被群落特性,估算红松针阔叶混交林森林生态系统不同组分CO2通量.利用涡度相关技术监测红松针阔叶混交林净生态系统交换量.探讨温度、光合有效辐射对森林生态系统CO2通量的影响.通过分析发现,在当年的气候条件下,该森林净生态系统交换量主要受土壤呼吸和叶片光合的影响.红松针阔叶混交林净生态系统交换量全年变化范围在-4.67~13.80μmol·m-2·s-1.该森林生态系统CO2通量在冬季和夏季里平均分别为-2.0和3.9μmol·m-2·s-1(24 h平均值).乔木、灌木和草本的初级生产力分别占阔叶红松林总初级生产力的89.7%,3.5%,6.8%.土壤呼吸是森林生态系统中最主要的CO2排放源,约占红松针阔叶混交林生态系统CO2排放的69.7%,植物叶片和枝干分别占15.2%和15.1%.在生长季和非生长季中红松针阔叶混交林净生态系统交换量分别占全年CO2通量的56.8%和43.2%.自养呼吸占总初级生产力的比值(Ra:GPP)为0.52(NPP:GPP=0.48).森林生态系统地下当年碳积累量占总初级生产力的52%.土壤呼吸占总初级生产力的60%.红松针阔叶混交林NPP为769.3 gC·m-2·a-1.该森林净生态系统交换量(NEE)为229.51 gC·m-2·a-1.涡度相关技术获得的该森林生态系统NEE低于箱式法获得的19.8%.
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利用Li-6400便携式CO2分析系统测定长白山原始阔叶红松林生态系统土壤呼吸、乔灌木的枝干呼吸和叶呼吸;同步监测森林小气候气象因子;建立土壤、树干、叶与环境因子间的模型.根据阔叶红松林植被群落的特性,估算阔叶红松林生态系统不同组分呼吸速率.结果表明,阔叶红松林生态系统呼吸具有明显的成熟林特征,生态系统总呼吸量为1602.8gC.m-2.整个生态系统年平均呼吸速率为(4.37±2.98)μmol.m-2.s-1(24h平均数).其中,土壤呼吸、枝干和叶呼吸分别占整个森林生态系统呼吸的63%、16%和21%.乔木、灌木和草本叶呼吸速率分别占阔叶红松林生态系统植物呼吸的89.82%、5.57%和4.61%.阔叶红松林生态系统呼吸速率与大气和土壤温度之间呈显著的指数关系.大气和土壤温度能分别反映阔叶红松林生态系统呼吸的87%和95%.
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目的研究过量Mg2+对土壤中脲酶、磷酸酶和过氧化氢酶活性的影响.方法通过在清洁土壤中投加不同质量浓度的MgC l2试剂,经过28 d的培养,期间在第1、3、7、14、28 d取样,测定土壤中的脲酶、磷酸酶和过氧化氢酶的活性.结果数据分析表明Mg2+对脲酶有激活作用,当Mg2+的质量分数为0.6%时,土壤脲酶活性提高最多,为91.6%,脲酶活性增加的程度为:0.6%>0.8%>0.4%>0.2%>1.0%>0,并且第1 d是观测脲酶变化的最佳时间.Mg2+对磷酸酶活性有先激活再抑制的作用,其活性在第3 d有大幅度增加,而从第14 d开始到第28 d,5个含不同质量分数Mg2+的土样,其磷酸酶活性全都低于空白试验。过氧化氢酶活性在试验的所有土样中均受到长效抑制.结论脲酶、磷酸酶和过氧化氢酶对Mg2+反映敏感,在Mg2+质量分数为0.6%时可以短期提高土壤肥力,但是长期大量的Mg2+介入土壤会严重影响土壤肥力,因此,可以考虑以Mg2+作为镁污染土壤的生态毒理指标.
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对青藏高原黄河源区不同退化程度高寒草地的土壤种子库土样用土壤分析筛进行浓缩,并以萌发法分析土壤种子库萌发种子数量和动态.结果表明,孔径0.25~2 mm的土壤分析筛分离土样中萌发种子可达萌发种子总量的85%~97%,而小于0.25 mm的土样中未发现种子.因此,用0.25 mm孔径大小的土壤筛对高寒草地土壤种子库土样进行大规模浓缩是一种方便、可靠的方法.4种不同退化程度高寒草地(A:未退化草甸;B:轻度退化草甸;C:中度退化草甸;D:重度退化草甸)的土壤种子库在实验室条件下萌发的种子数量分别为:A 1 194~3 744粒/m2,平均2 421.3粒/m2;B 5 376~1 0912粒/m2,平均7 786.7粒/m2;C 2 304~1 3216粒/m2,平均8 695.5粒/m2;D 4 768~12 352粒/m2,平均8 125.9粒/m2.除样地A外,其它3个样地的可萌发种子数量差异不大.单子叶植物种子在培养到d 10左右开始萌发,双子叶植物在5~7 d内开始萌发,前者3 wk后基本不再萌发,后者5 wk左右停止萌发.4个样地土壤种子库种子萌发主要集中在第2~3周,并表现出近似单峰型格局.图1表3参39