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41.
Abstract. This paper describes the successional status of the vegetation in a clear‐felled dry oak woodland at the edge of the Hungarian forest‐steppe zone on the basis of a vegetation map. Due to a varied geomorphology of the colline landscape several so‐called landscape units can be distinguished. The patchwork on the vegetation map is evaluated using several, morphology‐based attributes (static morphological indices) traditionally applied in landscape ecology. In the ca. 100 years that elapsed since forest clear‐cut, xeric grassland species and steppe elements became more abundant and the former xeromesophilous vegetation – containing even some woodland components – is slowly turning into xeric grassland communities. The vegetation units mapped can be arranged into a hypothetical succession scheme in which successional distances (the number of steps between two stages) are determined. Based on the distances thus obtained, a new dynamic morphological index is introduced. This is applied to each landscape unit for the dynamic evaluation of successional vegetation, its results being compared with those obtained by static morphological indices. 相似文献
42.
M. Yaneshita S. Kaneko T. Sasakuma 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(5):751-756
A RFLP linkage map of Zoysia spp. (2n=40), a warm-season turfgrass, was constructed by using the self-pollinated progenies obtained from an interspecific
hybrid. Out of 115 DNA clones tested, 100 (87.0%), including 55 genomic clones, 38 cDNA clones, and seven gene clones encoding
photosynthetic enzymes showed allelic-RFLP banding patterns among the parental accessions. We found that 26 probes detected
two or more loci segregating in the self-pollinated progenies independently. The RFLP linkage map of Zoysia spp. consists of 115 loci in 22 linkage groups ranging in size from 12.5 cM to 141.3 cM with a total map distance of 1506 cM.
Six RFLP loci (5.4%) showed significant segregation distortion (P<0.01). Two loci out of six were mapped to linkage group II, and another two loci were mapped to group VII. In the RFLP linkage
map of zoysiagrass, five pairs of linkage groups sharing a series of duplicated loci with approximately the same order were
identified. Therefore, we conclude that Zoysia spp. with 2n=40 should be considered as allotetraploids, which might have evolved from progenitors with a basic chromosome
number of ten (x=10).
Received: 20 March 1998 / Accepted: 17 September 1998 相似文献
43.
44.
Nedim Mutlu Phillip N. Miklas Dermot P. Coyne 《Molecular breeding : new strategies in plant improvement》2006,17(2):127-135
Resistance (R) genes containing nucleotide-binding site (NBS)-leucine rich repeats (LRR) are the most prevalent types of R
gene in plants. The objective of this study was to develop PCR-based R-gene analog polymorphism (RGAP) markers for common
bean (Phaseolus vulgaris L). Twenty degenerate primers were designed from the conserved kinase-1a (GVGKTT) and hydrophobic domains (GLPLAL) of known
NBS-LRR type R-genes and from EST databases. Sixty-six of the 100 primer combinations tested yielded polymorphism. Thirty-two
RGAP markers were mapped in the BAT 93/Jalo EEP558 core mapping population for common bean. The markers mapped to 10 of 11
linkage groups with a strong tendency for clustering. In addition, the RGAP markers co-located, on six linkage groups, with
15 resistance gene analogs (RGAs) that were previously mapped in other populations of common bean. The distance between the
priming sites in NBS-LRR type R-genes is around 500 bp. Of the 32 RGAP markers, 19 had sizes larger and 13 less than 500 bp.
RGAP markers mapped close to known R-genes on B11, and to QTLs for resistance on B1, B2, B6, B7, B8, B10, and B11. RGAP appears
to provide a useful marker technique for tagging and mapping R-genes in segregating common bean populations, discovery of
candidate genes underlying resistance QTL, and future cloning of R-genes in common bean. 相似文献
45.
Molecular Tagging and Mapping of Quantitative Trait Loci for Lint Percentage and Morphological Marker Genes in Upland Cotton 总被引:6,自引:0,他引:6
Wang-Zhen Guo Guo-Jia Ma Yi-Chao Zhu Chen-Xin Yi Tian-Zhen Zhang 《植物学报(英文版)》2006,48(3):320-326
Using 219 F2 Individuals developed by crossing the genetic standard line TM-1 and the multiple dominant marker line T586 In Gossyplum hirsutum L., a genetic linkage map with 19 linkage groups was constructed based on simple sequence repeat (SSR) markers. Compared with our tetraploid backboned molecular genetic map from a (TM-1xHal 7124)xTM-1 BC1 population, 17 of the 19 I|nkage groups were combined and anchored to 12 chromosomes (sub-genomes). Of these groups, four morphological marker genes In T586 had been mapped Into the molecular linkage map. Meanwhile, three quantitative trait loci for lint percentage were tagged and mapped separately on the A03 linkage group and chromosome 6. 相似文献
46.
Complete maps of IS1, IS2, IS3, IS4, IS5, IS30 and IS150 locations in Escherichia coli K12 总被引:8,自引:0,他引:8
Summary In this paper complete distribution maps are presented of the seven IS elements 1, 2, 3, 4, 5, 30 and 150. These maps were obtained during the construction of an almost complete restriction map of the Escherichia coli genome of K12 strain BHB2600. The positions of IS elements were correlated to this map. The distribution of integration sites of all IS types is nonrandom. Besides a large gap from 79 min to 96 min, there is a pronounced IS cluster at 6 min and another at 97 min, map locations that have low gene incidences on the classical map. One cluster coincides with a region of IS induced rearrangements. The IS distribution pattern was compared to patterns of strains W3110 and HB101. 相似文献
47.
48.
Xiaojing Zhou Youlin Xia Xiaoping Ren Yulin Chen Li Huang Shunmou Huang Boshou Liao Yong Lei Liyin Yan Huifang Jiang 《BMC genomics》2014,15(1)
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49.
50.
Dan E. Wells Laura Gutierrez Zhenkang Xu Vladimir Krylov Jaroslav Macha Kerstin P. Blankenburg Matthew Hitchens Larry J. Bellot Mary Spivey Derek L. Stemple Andria Kowis Yuan Ye Shiran Pasternak Jenetta Owen Thu Tran Renata Slavikova Lucie Tumova Tereza Tlapakova Eva Seifertova Steven E. Scherer Amy K. Sater 《Developmental biology》2011,(1):507
We present a genetic map for Xenopus tropicalis, consisting of 2886 Simple Sequence Length Polymorphism (SSLP) markers. Using a bioinformatics-based strategy, we identified unique SSLPs within the X. tropicalis genome. Scaffolds from X. tropicalis genome assembly 2.0 (JGI) were scanned for Simple Sequence Repeats (SSRs); unique SSRs were then tested for amplification and polymorphisms using DNA from inbred Nigerian and Ivory Coast individuals. Thus identified, the SSLPs were genotyped against a mapping cross panel of DNA samples from 190 F2 individuals. Nearly 4000 SSLPs were genotyped, yielding a 2886-marker genetic map consisting of 10 major linkage groups between 73 and 132 cM in length, and 4 smaller linkage groups between 7 and 40 cM. The total effective size of the map is 1658 cM, and the average intermarker distance for each linkage group ranged from 0.27 to 0.75 cM. Fluorescence In Situ Hybridization (FISH) was carried out using probes for genes located on mapped scaffolds to assign linkage groups to chromosomes. Comparisons of this map with the X. tropicalis genome Assembly 4.1 (JGI) indicate that the map provides representation of a minimum of 66% of the X. tropicalis genome, incorporating 758 of the approximately 1300 scaffolds over 100,000 bp. The genetic map and SSLP marker database constitute an essential resource for genetic and genomic analyses in X. tropicalis. 相似文献