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1.
正交设计优化果梅ISSR反应体系   总被引:16,自引:0,他引:16  
以果梅(PrunusmumeSieb.etZucc.)品种鸳鸯梅为试材,采用改良的CTAB法提取果梅嫩叶DNA,利用正交设计L16(45)探讨Mg2+、dNTPs、引物、TaqDNA聚合酶及模板DNA用量对果梅ISSR-PCR反应的影响,正交试验的结果采用直观分析和方差分析相结合。建立了果梅的ISSR-PCR优化反应体系,在20μL反应体系中含2μL10×Buffer,2.5mmol·L-1Mg2+,0.2mmol·L-1dNTPs,0.32μmol·L-1引物,20~80ng模板DNA,0.75UTaqDNA聚合酶。在此基础上探讨了引物UBC840的最适退火温度、最佳循环次数及延伸时间,引物UBC840的最适退火温度为50.6℃。应用该优化反应体系,用2个不同引物对19份果梅资源DNA进行ISSR-PCR扩增,结果显示优化的反应体系具有较高的稳定性。  相似文献
2.
Human settlement is a formidable agent of change affecting fundamental ecological processes. Decisions governing these land-use changes occur almost exclusively at the local level and, as a result, they are made at many different locations and times. Consequently, it is difficult for ecologists to provide needed scientific support for these choices. We built an information system designed to support conservation decisions at local scales by offering data over the Internet. We collaborated with local stakeholders (e.g., developers, planners, politicians, land owners, environmental activists) to design the system. This collaboration produced several generalizations about effective design of information systems to support conservation. The most important of these is the idea that ecological data and analysis must be understood by those who will be affected by the decisions. Also, planning for conservation is a process that uses scientific data, but that ultimately depends on the expression of human values. A major challenge landscape ecologists face is to extend general landscape principles to provide specific scientific information needed for local land-use planning.  相似文献
3.
正交设计在黄金鱼花组织培养中的应用   总被引:10,自引:0,他引:10       下载免费PDF全文
李艳  王青  李英慧  王火旭 《园艺学报》2001,28(6):570-571
 用正交设计法研究了4 种激素对黄金鱼花叶片诱导愈伤组织的影响。结果显示,诱导黄金鱼花愈伤组织产生的最佳激素配比为: MS + 2 ,4-D 1 mg/L + 6-BA 1 mg/L + NAA 1 mg/L , 有2 ,4-D 的培养基中愈伤组织诱导率明显高于没有2 ,4-D 的培养基, IBA 对愈伤组织的诱导有抑制作用。  相似文献
4.
葡萄目标起始密码子多态性反应体系的优化   总被引:7,自引:1,他引:6  
SCoT标记是一种新型目的基因分子标记方法,采用L16(45)正交试验和单因素试验2种方法优化了葡萄SCoT-PCR反应体系,结果表明正交试验中关键影响因子为dNTPs浓度,单因素试验中为dNTPs和Mg2+浓度。综合2种方法,优化的葡萄SCoT-PCR反应体系为:Mg2+2.0 mmol.L-1、dNTPs 0.3 mmol.L-1、Taq酶1.0 U、引物0.3μmol.L-1、DNA模板30 ng,总体积20μL。扩增程序为:94℃预变性5 min;94℃变性1 min,54℃退火1 min,72℃复性2 min,34个循环;最后72℃延伸8 min。该反应体系在20个葡萄品种的验证中表现出良好的稳定性和可重复性,该反应体系的建立为葡萄种质遗传多样性评价、基因组分析、指纹图谱构建、分子标记辅助选择育种等研究提供了新的技术手段。  相似文献
5.
基于光照的日光温室总体尺寸确定方法研究   总被引:6,自引:0,他引:6  
从日光温室内部光环境变化入手,以满足作物获得充足光照为目标,提出以保证冬至日正午前后4 h内,太阳光对温室前屋面透过后的辐射照度衰减率不超过2%,以及保证栽培区最后一排作物的冠层全天受到太阳照射为条件,建立了一套日光温室总体尺寸的取值方法.并与典型区域的日光温室建造规范进行比对.结果表明:该方法具有较高的可信度,能够为科学指导我国日光温室规范化建设提供理论参考.  相似文献
6.
Detection of structured spatial variation and identification of spatial scales are important aspects of ecological studies. Spatial structures can correspond to physical features of the environment or to intrinsic characteristics of ecological processes and phenomena. Spatial variability has been approached through several techniques such as classical analysis of variance, or the calculation of fractal dimensions, correlograms or variograms. Under certain assumptions, these techniques are all closely related to one another and represent equivalent tools to characterize spatial structures.Our perception of ecological variables and processes depends on the scale at which variables are measured. We propose simple nested sampling designs enabling the detection of a wide range of spatial structures that show the relationships among nested spatial scales. When it is known that the phenomenon under study is structured as a nested series of spatial scales, this provides useful information to estimate suitable sampling intervals, which are essential to establish the relationships between spatial patterns and ecological phenomena. The use of nested sampling designs helps in choosing the most suitable solutions to reduce the amount of random variation resulting from a survey. These designs are obtained by increasing the sampling intensity to detect a wider spectrum of frequencies, or by revisiting the sampling technique to select more representative sampling units.  相似文献
7.
榆黄蘑菌丝体多糖提取工艺的研究   总被引:4,自引:0,他引:4  
以榆黄蘑新鲜菌丝体为材料,对多糖提取的最优化工艺进行了研究。应用均匀正交设计试验方法,得到榆黄蘑多糖提取的最优化工艺为:超声波破壁时间12min,提取时间4h,提取温度70℃,菌丝密度250mg/mL(鲜重)。  相似文献
8.
Human-mediated vegetation switches as processes in landscape ecology   总被引:4,自引:1,他引:3  
Switches are processes in which there is positive feedback between vegetation and environment. Landscape features can be created and modified by switches. The concept has previously been used with physical factors and non-human animals as the switch mediator, i.e. the factor which the vegetation modifies and which in turn affects the vegetation. Here, the switch concept is extended to include some types of human behaviour as possible switch mediators. With this extension, the switch concept can explain the impact on the landscape of some types of human behaviour. Examples are given of the behaviour of mower drivers, mowing up to a boundary which they create and/or maintain, and of walkers trampling tracks which they create and/or maintain. Other possibilities are discussed briefly. It is concluded that the concept of a human-mediated switch can unify the study of human behaviour, vegetation processes and landscape ecology.  相似文献
9.
菊花品种花色表型数量分类研究   总被引:4,自引:0,他引:4       下载免费PDF全文
洪艳  白新祥  孙卫  贾锋炜  戴思兰 《园艺学报》2012,39(7):1330-1334
 为了精确定义菊花不同品种的花色,以811 个菊花品种为试验材料,利用色差仪测色的方法对其花色表型值进行测定并进行数量分类研究。结果发现:聚类分析方法得到的分类结果不能完全表征菊花花色的分类特点;ISCC-NBS 色名表示法对花色的定义更为准确,使用该方法将菊花品种花色分为9类色系,整理出了不同色系表型参数分布范围。在此基础上,对菊花品种的花色表型分布特点进行了分析。  相似文献
10.
山葵试管苗快繁体系优化初探   总被引:3,自引:0,他引:3       下载免费PDF全文
 通过最优回归设计, 利用6-BA、NAA和维生素C不同浓度配比对山葵试管苗增殖系数进行调查, 结果表明: 当6-BA、NAA、维生素C的浓度分别为1.2504、0和1.9668 mg/L时, 增殖系数可达到6.8380。壮苗比较适宜的生根培养基为1/2MS +NAA 0.01 mg/L或者1/2MS, 生根率达90%以上。未生根的壮苗试管苗可直接移栽驯化, 且生根率可达80%以上, 能进一步降低种苗的生产成本。  相似文献
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