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排序方式: 共有114条查询结果,搜索用时 15 毫秒
1.
以利用DNA ISSR分子标记逐级区分品种为主要研究目标,通过ISSR引物的设计与实验筛选,取得了进展。该方法类似于经典的植物形态检索表式的分类策略,不同之处在于利用基因组DNA分子性状作为品种分类的依据,即"ISSR引物结合位点"与"DNA ISSR片段长度差异"的组合信息。该方法不仅可以有效鉴定品种,而且可以很容易地生成富含遗传变异信息的0、1矩阵,通过运算揭示品种间的遗传关系与演化规律。该方法成本低廉、操作便捷,对于建立客观、科学的牡丹及芍药品种分类体系,对于芍药属品种种质资源的保存、评价与合理利用具有重要价值。应该加大支持力度推进其实际应用。  相似文献   
2.
贵州赫章县野生韭菜资源调查与营养成分分析   总被引:1,自引:0,他引:1  
贵州省是野生葱类资源的重要分布地区,特别是赫章县野生韭菜的分布面积较广。为了详细了解和研究野生韭菜的分布,对赫章县野生韭菜地理分布、生境及气候进行了专题调查,并对其主要营养成分进行了分析。结果发现,赫章县主要分布有3种野生韭菜,它们分别为多星韭(Allium wallichii Kunth.)、卵叶韭(Allium ovalifolium Hand.-Mazz.暂定名)和近宽叶韭(Allium hookeri Thwaites暂定名);对17种水解氨基酸检测表明,除脯氨酸外,野生韭菜的各种氨基酸含量均较栽培韭(Allaum tuberosum Rottler ex Spreng.)的含量高;而野生韭的含糖量却明显低于普通的栽培韭;在9种微量元素中,卵叶韭的锰、锌、铁的含量明显高于栽培韭和其他野生韭菜;对4种重金属检测表明,镉的含量在3种野生韭中均超标,特别是卵叶韭中的镉含量明显高于栽培韭和其他2种野生韭,卵叶韭的砷、汞、铅的含量也较高,超出了国家限量标准;原生境的多星韭的叶片和薹维生素C含量均高于栽培韭菜。本次调查中的野生韭菜资源生物学特征有明显特异性,营养成分存在很大差异,对这些资源的收集与保存将对丰富我国韭菜资源保存的多样性具有重要意义,对韭菜营养品质改良具有很大的开发和利用价值。  相似文献   
3.
The conflict between cultivated land protection and economic development has become increasingly acute in recent years. Despite, intensive researches made on this conflict, little attention has been paid to the spatial correlation of variables. In view of this, the paper introduces the spatial panel regression model to estimate, and test whether the relationship between economic growth and cultivated land conversion conforms to Kuznets curve. Research results show that the area of converted cultivated land in China exhibits strong spatial auto-correlation; the spatial panel model with time effect and fixed effect is more stable and significant than conventional panel mode, and that the relationship between economic growth and cultivated land conversion agrees with the inverted U-shape of Kuznets curve, with inflection point occurring when average per capita GDP reaches ¥31330.93 (calculated at comparable price of 1999). On the basis of analysis, it is suggested that the government, with a view to developing economy alongside protecting cultivated land, should attach more importance to land use and planning in the future, pay more attention to the spatial correlation of cultivated land planning in adjacent areas and make greater efforts to increase the input–output ratio of land.  相似文献   
4.
In this work, I tested the premise that the distribution of a group of few common bird species can be used to predict bird species hotspots in Central Italy. The data on bird observations were collected on 530 sampled sites (150 in cultivated, 150 in forest, 150 in grassland and 80 in urban and peri-urban environments). In each environment, sampled sites with values of bird species richness in the upper than third quartile were classified as high species richness spots (HSRS), while sites with lower bird species richness were classified as non-HSRS (binary classification system).Generalized Linear Models (GLM) were applied using HSRS or non-HSRS as binomial response variable and bird species occurrence was used as the predictor variable. All selected models showed “fair” or “good” capacities to predict the avian hotspots, using only few common birds (4–6) species. However, bird species selected as predictors were different on each environment. In more natural environments (grassland, forest), specialist species were selected, while in most disturbed environments (cultivated and urban) both generalist and specialist species were selected. The results are in agreement with other studies which show how homogenization of bird communities is strongly correlated to landscape disturbance. The findings supports the hypothesis that indicators have to incorporate both specialists and generalist’s species simultaneously. Furthermore, the groups of birds selected as surrogates are easy to detect and this makes it possible to involve citizen-science programmes in obtain data. This approach can be a cheap and efficient and can help to significantly speed up the process of assessing ecosystems that might be under threat.  相似文献   
5.
本研究选取黄麻属(Corchorus)2个栽培品种及其4个野生类型和3个野生近缘种为材料,采用常规根尖压片法对黄麻属供试材料的染色体数目和核型进行研究。结果表明:染色体数目均为2n=14。核型公式分别为:宽叶长果(长果黄麻栽培种)2n=2x=14=14m(4SAT);南阳野生长果(长果黄麻野生类型)2n=2x=14=14m(2SAT);坦桑尼亚野生长果(长果黄麻野生类型)2n=2x=14=2M+12m;闽麻5号(圆果黄麻栽培种)2n=2x=14=12m+2sm;爱店野生圆果(圆果黄麻野生类型)2n=2x=14=14m ;廉江野生圆果(圆果黄麻野生类型) 2n=2x=14=4M+10m;假黄麻(黄麻属野生近缘种)2n=2x=14=2M+12m;假长果(黄麻属野生近缘种)2n=2x=14=2M+12m;甜麻(黄麻属野生近缘种)2n=2x=14=14m。其中除了宽叶长果核型分类为1B外,其他的都为1A型。本文还讨论了黄麻野生近缘种甜麻的分类学地位。  相似文献   
6.
The Hazard analysis and critical control points (HACCP) is a preventive system which seeks to ensure food safety and security. It allows product protection and correction of errors, improves the costs derived from quality defects and reduces the final overcontrol. In this paper, the system is applied to the line of cultivation of mushrooms and other edible cultivated fungi. From all stages of the process, only the reception of covering materials (stage 1) and compost (stage 3), the pre-fruiting and induction (step 6) and the harvest (stage 7) have been considered as critical control point (CCP). The main hazards found were the presence of unauthorized phytosanitary products or above the permitted dose (stages 6 and 7), and the presence of pathogenic bacteria (stages 1 and 3) and/or heavy metals (stage 3). The implementation of this knowledge will allow the self-control of their productions based on the system HACCP to any plant dedicated to mushroom or other edible fungi cultivation.  相似文献   
7.
The ongoing destruction of tropical rainforests has increased the interest in the potential value of tropical agroforests for the conservation of biodiversity. Traditional, shaded agroforests may support high levels of biodiversity, for some groups even approaching that of undisturbed tropical forests. However, it is unclear to what extent forest fauna is represented in this diversity and how management affects forest fauna in agroforests. We studied lower canopy ant and beetle fauna in cacao agroforests and forests in Central Sulawesi, Indonesia, a region dominated by cacao agroforestry. We compared ant and beetle species richness and composition in forests and cacao agroforests and studied the impact of two aspects of management intensification (the decrease in shade tree diversity and in shade canopy cover) on ant and beetle diversity. The agroforests had three types of shade that represented a decrease in tree diversity (high, intermediate and low diversity). Species richness of ants and beetles in the canopies of the cacao trees was similar to that found in lower canopy forest trees. However, the composition of ant and beetle communities differed greatly between the agroforest and forest sites. Forest beetles suffered profoundly from the conversion to agroforests: only 12.5% of the beetle species recorded in the forest sites were also found in the agroforests and those species made up only 5% of all beetles collected from cacao. In contrast, forest ants were well represented in agroforests, with 75% of all species encountered in the forest sites also occurring on cacao. The reduction of shade tree diversity had no negative effect on ants and beetles on cacao trees. Beetle abundances and non-forest ant species richness even increased with decreasing shade tree diversity. Thinning of the shade canopy was related to a decrease in richness of forest ant species on cacao trees but not of beetles. The contrasting responses of ants and beetles to shade tree management emphasize that conservation plans that focus on one taxonomic group may not work for others. Overall ant and beetle diversity can remain high in shaded agroforests but the conservation of forest ants and beetles in particular depends primarily on the protection of natural forests, which for forest ants can be complemented by the conservation of adjacent shaded cacao agroforests.  相似文献   
8.
Botanical pesticides play increasingly important roles in the control of agricultural pests. In this study, the insecticidal effects, specifically the repellent action and contact toxicity, of the essential oil extracted from Chinese chive (EOC) against Plutella xylostella larvae were confirmed. The mechanisms of repellent’s action were studied using electroantennograms (EAGs), and the effects on glutathione S‐transferase (GST), carboxylesterase (CarE), and acetyl cholinesterase were investigated after EOC treatments. The EOC affected the EAG results and inhibited the activities of GST and CarE in treated P. xylostella larvae, which could explain its insecticidal effects. And, four pyrazines showed greater repellent activities than that of the EOC, which was confirmed as the main active compounds of EOC.  相似文献   
9.
Until now, very little was known about the agriculture of the Late Iron Age in Hungary. This paper describes the first results of an archaeobotanical examination of a late Iron Age, Celtic settlement in Budapest. It is the first systematically sampled and representatively investigated site of this time period in Hungary. Most of the samples come from different types of pits, which were subjectively sampled. The macrofossils were carbonised and, apart from many seeds and fruit stones, consisted mostly of charcoal. Among the seed remains both cultivated and wild species were present. The spectrum of cultivated plants was marked by a large number of cereals. The dominant cereals were Triticum spelta L. (spelt wheat) and Panicum millaceum L. (broomcorn millet), but also common were Avena sativa L., Avena sp. (oats), Triticum monococcum L. (einkorn), Hordeum vulgare L. (barley); Triticum aestivum/durum/turgidum L./Desf./L., incl. T. compactum Host. (bread wheat, including club wheat). Secale cereale L. (rye) and Triticum dicoccum (Schrank) Schübl. (emmer) were rare and seemed to be less important. The weeds and synanthropic vegetation, including ruderals, were represented by many taxa, and some of them also occurred in large amounts. The main cereals were sown as winter crops, judging from the rarely occurring of plants accompanying the cereals. Wild fruits contributed to the daily diet, too – as seen from the stones of Cornus mas (cornelian cherry), Crataegus sp. (hawthorn) and Prunus spinos (sloe, blackthorn). There were no finds of cultivated fruits. Received October 19, 2001 / Accepted January 30, 2002  相似文献   
10.

Background

Cultivated peanut, or groundnut (Arachis hypogaea L.), is an important oilseed crop with an allotetraploid genome (AABB, 2n = 4x = 40). In recent years, many efforts have been made to construct linkage maps in cultivated peanut, but almost all of these maps were constructed using low-throughput molecular markers, and most show a low density, directly influencing the value of their applications. With advances in next-generation sequencing (NGS) technology, the construction of high-density genetic maps has become more achievable in a cost-effective and rapid manner. The objective of this study was to establish a high-density single nucleotide polymorphism (SNP)-based genetic map for cultivated peanut by analyzing next-generation double-digest restriction-site-associated DNA sequencing (ddRADseq) reads.

Results

We constructed reduced representation libraries (RRLs) for two A. hypogaea lines and 166 of their recombinant inbred line (RIL) progenies using the ddRADseq technique. Approximately 175 gigabases of data containing 952,679,665 paired-end reads were obtained following Solexa sequencing. Mining this dataset, 53,257 SNPs were detected between the parents, of which 14,663 SNPs were also detected in the population, and 1,765 of the obtained polymorphic markers met the requirements for use in the construction of a genetic map. Among 50 randomly selected in silico SNPs, 47 were able to be successfully validated. One linkage map was constructed, which was comprised of 1,685 marker loci, including 1,621 SNPs and 64 simple sequence repeat (SSR) markers. The map displayed a distribution of the markers into 20 linkage groups (LGs A01–A10 and B01–B10), spanning a distance of 1,446.7 cM. The alignment of the LGs from this map was shown in comparison with a previously integrated consensus map from peanut.

Conclusions

This study showed that the ddRAD library combined with NGS allowed the rapid discovery of a large number of SNPs in the cultivated peanut. The first high density SNP-based linkage map for A. hypogaea was generated that can serve as a reference map for cultivated Arachis species and will be useful in genetic mapping. Our results contribute to the available molecular marker resources and to the assembly of a reference genome sequence for the peanut.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-351) contains supplementary material, which is available to authorized users.  相似文献   
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