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1.
One of the major problems faced by conservation biologists is the allocation of scarce resources to an overwhelmingly large number of species in need of preservation efforts. Both demographic and genetic information have been brought to bear on this problem; however, the role of information obtained from genetic markers has largely been limited to the characterization of gene frequencies and patterns of diversity. While the genetic consequences of rarity may be a contributing factor to endangerment, it is widely recognized that demographic factors often may be more important. Because patterns of genetic marker variation are influenced by the same demographic factors of interest to the conservation biologist, it is possible to extract useful demographic information from genetic marker data. Such an approach may be productive for determining plant mating systems, inbreeding depression, effective population size, and metapopulation structure. In many cases, however, data consisting only of marker frequencies are inadequate for these purposes. Development of genealogical based analytical methods coupled with studies of DNA sequence variation within and among populations is likely to yield the most information on demographic processes from genetic marker data. Indeed, in some cases it may be the only means of obtaining information on the long-term demographic properties that may be most useful for determining the future prospects of a species of interest. 相似文献
2.
Genetic variability and association of ISSR markers with some biochemical traits in mulberry (Morus spp.) genetic resources available in India 总被引:2,自引:0,他引:2
Prasanta K. Kar Prem P. Srivastava Arvind K. Awasthi S. Raje Urs 《Tree Genetics & Genomes》2008,4(1):75-83
Utilizing intersimple sequence repeat (ISSR) markers, 18 mulberry (Morus spp.) germplasm collections were studied for genetic variability, phylogenetic relationship, and association with protein
and sugar content. The genetic polymorphism exhibited by ISSR primers was 100%, and the genetic diversity recorded among the
mulberry accessions had an average of 0.263 ± 0.094. Dendrogram (unweighted pair group method analysis) clustered the mulberry
accessions into two major groups, one comprised the accessions collected from north or northeast regions of India, and the
other comprised three subclusters and one isolate, i.e., Assamjati, a collection from Assam. Another subcluster contained
accessions collected from Kerala, which belong to Morus indica. These accessions of M. indica from Kerala were found to be genetically diverse from north and northeast India. Multidimensional scaling of the ISSR data
clearly separated the mulberry accessions according to their genetic diversity and protein content. Mulberry accessions were
arbitrarily grouped into three classes viz. very low, moderate, and high in terms of protein and sugar content using standard
statistical programs. Stepwise multiple regression analysis identified four ISSR markers (8351,600, 8355,600, 8222,500, and 8072,500) associated with protein content with highly positive correlation (p < 0.001) with linear curves with high F values (18.055 to 48.674; p < 0.001). In case of sugar content, four ISSR markers viz. 812900, 8171,500, 8261,500, and 8108,000 showed negative correlation. Hence, DNA markers for proteins seem promising and may be used in marker-assisted breeding program. 相似文献
3.
Euryodendron excelsum is a critically endangered tertiary relict plant endemic to China. It has only one population remaining in Ba Jia Zhen of Yangchun, Guangdong. In this study, we discovered 25 microsatellite markers from E. excelsumusing a Fast Isolation by Amplified Fragment Length Polymorphism of Sequences COntaining Repeats (FIASCO) protocol. Thirteen loci demonstrated polymorphisms, with the number of alleles per locus ranging from 2 to 13. Values for observed and expected heterozygosity ranged from 0.176 to 1.000 and from 0.261 to 0.889, respectively. Three loci (ZXM-17, ZXM-54, and ZXM-92) were found to significantly deviate from Hardy-Weinberg equilibrium. In addition, five of 13 loci could be successfully cross-amplified in Ternstroemia gymnanthera. These microsatellite loci may help to further survey the adaptive evolution and genetic variation of E. excelsum for guiding its conservation. 相似文献
4.
5.
M. S. ISLAM J. M. TAO Q. F. GENG C. L. LIAN T. HOGETSU 《Molecular ecology resources》2006,6(4):1111-1113
Kandelia candel is an important mangrove tree species of family Rhizophoraceae. Here we isolated eight codominant compound microsatellite simple sequence repeat (SSR) loci from K. candel. Our isolated loci provided compound SSR markers with polymorphism of three to 11 alleles per locus. The expected and observed heterozygosities ranged from 0.230 to 0.887 and from 0.083 to 1.00, respectively. These markers would be the useful tools for analysing questions concerning population genetic structure and mating system of K. candel. 相似文献
6.
G. S. C. BUSO Z. P. S. AMARAL R. P. V. BRONDANI M. E. FERREIRA 《Molecular ecology resources》2006,6(1):252-254
Efforts to develop molecular tools for genetic analysis and breeding of common bean in the tropics are still limited. The number of microsatellite markers available for the crop is small compared to other crops of similar social and economic importance. As part of a project to broaden the use of molecular tools in bean breeding, a genomic library enriched for AG/TC repeat sequences was constructed for Phaseolus vulgaris. Twenty microsatellite markers were initially developed and 10 were characterized using a panel of 85 representative accessions of the bean gene bank. The number of alleles per marker ranged from three to 10. The polymorphism information content (PIC) varied from 0.23 to 0.80. The results indicate that the new markers can be readily used in genetically analysis of common bean. 相似文献
7.
Inter simple sequence repeat (ISSR) marker assay was employed to validate the genetic fidelity of Swertia chirayita plantlets multiplied in vitro by axillary multiplication upto forty-two passages. Sixteen ISSR primers generated a total of 102 amplicons among the tissue-cultured
plants. Forty-eight amplicons were amplified in the outlier (a Swertia species). The outlier (negative control) was employed to rule out the possibility that the invariant fingerprint was due
to chance alone and that the ISSR technique employed was not discriminatory enough to detect the off-types. A homogenous amplification
profile was observed for all the micropropagated plants. The results confirmed the clonal fidelity of the tissue culture-raised
S. chirayita plantlets and corroborated the fact that axillary multiplication is the safest mode for multiplication of true to type plants. 相似文献
8.
LI MINGFANG ZHENG XUEQING ZHU YONGQIANG WANG XIANGSHE LIANG SUYU LI LEI WU XINGRONG 《Molecular ecology resources》2006,6(4):1205-1207
Sixteen microsatellite loci were isolated from lychee (Litchi chinensis), all of which exhibited polymorphism (two or three alleles per locus), with levels of heterozygosity ranging from 0.021 to 0.900. These loci can help assess the genetic structure of lychee. 相似文献
9.
We developed eight polymorphic microsatellite markers from the Sachalin fir (Abies sachalinensis Masters). The number of alleles per locus ranged from eight to 31, with an average of 21.4. The observed and expected heterozygosities ranged from 0.656 to 0.937 and from 0.710 to 0.945, respectively. These markers will be available for population genetic studies and parentage analysis. 相似文献
10.
Alternaria alternata is of major significance as a food and feed contaminant and is able to produce a range of mycotoxins that may elicit adverse effects in both animals and humans. We describe the isolation and characterization of five microsatellite markers for studying A. alternata. Marker polymorphism was screened in 64 isolates of A. alternata. The number of alleles per locus ranged from eight to 24, and allelic diversity ranged from 0.425 to 0.882. These markers will be useful in the study of relationships and population genetics amongst isolates of A. alternata. 相似文献