ISSN 2736-1756
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Full Length Research Paper
Analysis of genetic diversity in bambara groundnut [Vigna subterranea (L.) Verdc] landraces using amplified fragment length polymorphism (AFLP) markers
Wazael H. Ntundu1, 2*, Inga C. Bach1, Jørgen L. Christiansen1 and Sven B. Andersen1
1Department of Agricultural Sciences, The Royal Veterinary and Agricultural University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
2Tropical Pesticides Research Institute, National Plant Genetic Resources Centre, P O Box 3024, Arusha, Tanzania.
Accepted 28 December 2003
Abstract
Amplified fragment length polymorphism (AFLP) was used to assess genetic diversity among 100 selected bambara groundnut [Vigna subterranea (L.) Verdc] landraces from a diverse geographic area of Tanzania. Eleven informative AFLP primer combinations generated a total of 49 scorable polymorphic amplification fragments across the bambara groundnut accessions. Genetic distances between all accessions based on Jaccard’s variability index ranged from 0.1 to 0.68, with a total average of 0.3. The results showed that bambara groundnut landraces from Tanzania form a genetically diverse population, and AFLP markers can be effectively employed to assess genetic diversity and to measure genetic relationship among accessions. Cluster analysis revealed that bambara groundnut from Tanzania constitute two major groups in line with their putative geographic origins, one genetically distinct group from the Southern agro-ecological zone and a mixed group with accessions from Central, Lake Victoria and Western agro-ecological zones. The clustering of accessions compared relatively well to clustering based on phenotypic characters. However, correlation of the AFLP marker distances with phenotypic distances showed r-values of 0.4 only.
Key words: AFLP markers, genetic diversity, landraces, Tanzania, Vigna subterranean.
Inga C. Bach, Jørgen L. Christiansen and Sven B. Andersen, Wazael H. Ntundu*
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Full Length Research Paper
Analysis of Tunisian date palm germplasm using simple sequence repeat primers
Zehdi S.1*, Sakka H.1, Rhouma A,2 Ould Mohamed Salem A.1 Marrakchi M.1 and Trifi M.1
1Laboratoire de Génétique, Immunologie and Biotechnologie, Faculté des Sciences de Tunis, Tunisia.
2Centre de Recherches Phoénicicoles, INRAT, Degache, Tunisia.
Accepted 11 February 2004
Abstract
Inter Simple Sequence Repeat (ISSR) markers involve polymerase chain reaction (PCR) amplification of DNA using a single primer composed of a microsatellite sequence. ISSR technology rapidly reveals high polymorphic fingerprints and determines genetic diversity. We used genetic markers generated from selected ISSR primers to assess genetic diversity among a set of Tunisian date palm varieties. Seven primers were used to cluster 12 date palm varieties and 77 polymorphic markers were sufficient to identify all of the varieties. These discrete molecular markers were used to estimate genetic distances among the 12 accessions and to examine their genetic relationships. Data analysis identified phenetic groups that were in agreement with those obtained according to agronomic traits and random amplified polymorphic DNA (RAPD) markers. Among the 12 simple sequence repeat (SSR) motifs tested, the most abundant were AG.
Key words: Genetic diversity, ISSR polymorphisms, date palm, Pheonix dactylifera.
Ould Mohamed Salem A Marrakchi M and Trifi M, Sakka H., Zehdi S.*, Rhouma A
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Full Length Research Paper
Comparative analysis and relationships of six important crop species chloroplast genomes using whole genome web-based informatics tools
Beatrice Kilel
School of Computational Sciences and Informatics, George Mason University, Fairfax, VA. 20110. USA. Email: [email protected].
Accepted 25 March 2004
Abstract
Using informatics tools to compare important species is now feasible as structural genomics continue in importance and establishment of structure-function relationships become a common way of comparative analysis. Currently, many of the technical issues involved in sequencing complete genomes have been solved. The smallness in size of chloroplast genomes facilitates being used for the discovery of disease resistance genes, introgression of important traits in transgenic plants, quantitative trait analysis and phylogenetic studies. Knowledge from this can be extrapolated to important crops like sorghum, millet, taro, and cassava that have not been fully sequenced. This study compared six important crop species using GeneOrder3.0 and CoreGenes2.0 web-based informatics tools using complete chloroplast genomes. Results obtained depict cases of major genome rearrangements, translocation, duplication, inversion and deletion of genes. Members of the poaceae family indicate a close relationship in the nature of conserved sequences while Oryza sativa and Chlorella vulgaris, which are not members of poaceae indicate no synteny. Gene content indicates that there are common sets of putative orthologs across the different species. Zea mays, O. sativa, Nicotiana tabacum, Spinacea oleracea, Triticum aestivum had 71 rows of putative orthologs (355 total) with one hypothetical protein (GI:11465969) in N. tabacum, which is homologous to cemA and ORF230 protein in O. sativa and Z. mays, respectively. There was a clear indication from these sets of putative orthologs that maturase-encoding genes were found only in the terrestrial plants and not in the unicellular organisms.
Key words: Chloroplast genomes, comparative analysis, informatics tools, whole genome, synteny.
Beatrice Kilel
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Full Length Research paper
Dockovdia cookarum infection and the prosobranch gastropod Lanistes libycus host in Omi Stream, Ago-Iwoye, south-western, Nigeria
O. M. Agbolade1*, A. B. Odaibo2
1Department of Biological Sciences, Olabisi Onabanjo University, P.M.B. 2002, Ago-Iwoye, Nigeria.
2Department of Zoology, University of Ibadan, Ibadan, Nigeria.
Accepted 31 December 2003
Abstract
Dockovdia cookarum infection was studied in relation to the abundance and size classes of Lanistes libycus from Omi Stream, Ago-Iwoye, Nigeria, between September 1997 and June 1998. 57.6% of the 262 L. libycus recorded were collected during periods of heavy rainfall. 17.2% (45) of the L. libycus examined had D. cookarum infection. The water mite prevalences were higher in rainy season than in dry season, and ranged between 3.0% and 44.4% monthly. L. libycus in 21-30 mm size class had the highest prevalence (73.3%). Intensity of infection was higher in rainy season than in dry season, and ranged between 1 and 6 mite(s)/snail. 2.6% of the L. libycus specimens in the 21-30 mm size class had concurrent D. cookarum and Chaetogaster limnaei infections.
Key words: Dockovdia cookarum, water mites, Lanistes libycus, freshwater molluscs, Nigeria
A. B. Odaibo, O. M. Agbolade*
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Short Communication
Isolation of a kernel oleoyl-ACP thioesterase gene from the oil palm Elaeis guineensis Jacq.
Omorefe Asemota*, Cha Tye San, Farida H. Shah
Department of Genetics, Faculty of Life Sciences, Universiti Kebangsaan Malaysia, 43600 Bangi, Malaysia.
Accepted 22 December 2003
Abstract
Thioesterases play a central role in determining chain lengths of fatty acids in oil storage tissues and have been isolated from a number of plant sources. While in some species enzymes that are specialized for the predominant fatty acids in the tissues examined have been found, in others, enzymes that are active over a broad range were observed. We have isolated a cDNA clone from the developing kernel of the oil palm Elaeis guineensis which encodes a thioesterase enzyme. Its highest homology was to the Brassica napus oleoyl-ACP thioesterase with which it had 72% homology at the nucleotide level, over the coding region examined, and 83% identity (90% positives) at the amino acid level.
Key words: Elaeis guineensis, kernel, oleoyl-ACP thioesterase, cDNA.
Farida H. Shah, Omorefe Asemota*, Cha Tye San
Page: 1 - 10
Research Article
Advanced Journal of Microbiology Research Vol. 2004
Available online at http://internationalscholarsjournals.org/journal/ajmr
© 2004 International Scholars Journals
Full Length Research paper
Colletotrichum circinans and Colletotrichum coccodes can be distinguished by DGGE analysis of PCR-amplified 18S rDNA fragments
Olajire Fagbola1+ and Mathew M. Abang2*
1Federal Biological Research Centre for Agriculture (BBA), Messeweg 11/12, D-38104 Braunschweig, Germany.
2German Collection of Microorganisms and Cell Cultures (DSMZ), Messeweg 11/12, D-38104 Braunschweig, Germany.
Accepted 29 December 2003
Abstract
The rDNA 18S region of Colletotrichum circinans and C. coccodes was amplified by PCR to evaluate this DNA region as a tool for species delineation. PCR amplification of the 18S of both species produced 1.65 Kb long fragments that covered most of the entire 18S rDNA molecule. DGGE analysis of the amplified fragments distinguished C. circinans from C. coccodes isolates. This result provides molecular evidence that supports the current treatment of C. circinans as a species distinct from C. coccodes, in spite of the failure of previous attempts at genetic differentiation of the two species based on RFLP analysis of the rDNA ITS region.
Key words: DGGE, Colletotrichum circinans, Colletotrichum coccodes, molecular differentiation, species delineation.
Mathew M. Abang, Olajire Fagbola
Page: 1 - 10