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Genetic Variation in Picea mariana × P. rubens Hybrid Populations Assessed with ISSR and RAPD Markers  [PDF]
Ramya Narendrula, Kabwe Nkongolo
American Journal of Plant Sciences (AJPS) , 2012, DOI: 10.4236/ajps.2012.36088
Abstract: Interspecific hybridization can result in significant shifts in allele frequencies. The objective of the present study was to assess the level of genetic variation in populations of P. mariana × P. rubens hybrids derived from artificial crosses. Progenies from backcross populations created through a series of controlled pollinations among P. mariana and P. rubens trees across the hybridization index were analyzed. Several Inter Simple Sequence Repeat (ISSR) and Random Amplified Polymorphic DNA (RAPD) primers were used to amplify genomic DNA samples from each population. ISSR primers produced from 30% to 52% polymorphic loci. The level of polymorphism was higher with RAPD markers, ranging from 57% to 76%. Overall, the two marker systems generated similar levels of polymorphic loci for P. mariana and P. rubens populations. No significant differences were found among the P. mariana × P. rubens populations analyzed and between the hybrids and the parental populations regardless of the molecular marker used. This confirms the genetic closeness of P. mariana and P. rubens species.
DEVELOPING OF THE METHODOLOGY FOR THE IDENTIFICATION OF PICEA ABIES L. CLONES BY USING ISSR MARKERS Разработка методики идентификации клонов плюсовых деревьев Ели обыкновенной (Picea abies l.) с использованием ISSR маркеров
Sheikina O. V.,Prohkorova A. A.,Novikov P. S.,Krivorotova T. N.
Polythematic Online Scientific Journal of Kuban State Agrarian University , 2012,
Abstract: The technology for the identification of Picea abies L. clones by using ISSR markers was developed. 9 ISSR primers ((GA)9T; (AC)8C; (CA)6RY; (CA)6RG; (CA)6(GT); (CA)6(AC); (AG)8T; (GA)8С и (AG)8YT) were recommended to use for genotypes detection. The selected primers have shown the high level of polymorphism. A total of 172 amplified fragments were found by the selected primers and 149 (86.6%) of them were polymorphic
Genetic similarity among strawberry cultivars assessed by RAPD and ISSR markers
Morales, Rafael Gustavo Ferreira;Resende, Juliano Tadeu Vilela;Faria, Marcos Ventura;Andrade, Marcela Carvalho;Resende, Luciane Vilela;Delatorre, Carla Andrea;Silva, Paulo Roberto da;
Scientia Agricola , 2011, DOI: 10.1590/S0103-90162011000600010
Abstract: most strawberry (fragaria × ananassa duchesne) cultivars used in brazil are developed in other countries, it became clear the need to start the strawberry breeding program in the country. to start a breeding program is necessary the genetic characterization of the germplasm available. molecular markers are important tools that can be used for this purpose. the objectives of the present study were to assess the genetic similarity among 11 strawberry cultivars using rapd and issr molecular markers and to indicate the possible promising crosses. the dna of the eleven strawberry cultivars was extracted and amplified by pcr with rapd and issr primers. the dna fragments were separated in agarose gel for the rapd markers and in polyacrylamide gel for the issr markers. the genetic similarity matrix was estimated by the jaccard coefficient. based on this matrix, the cultivars were grouped using the upgma method. the dendogram generated by the rapd markers distributed the cultivars in three groups while the issr markers generated two groups. there was no direct relationship between the marker groups when the two types of markers were compared. the grouping proposed by the issr markers was more coherent with the origin and the genealogy of the cultivars than that proposed by the rapd markers, and it can be considered the most efficient method for the study of genetic divergence in strawberry. the most promising crosses, based on the genetic divergence estimated from the rapd and issr molecular data were between the tudla and ventana and the oso grande and ventana cultivars, respectively.
Near-saturated and complete genetic linkage map of black spruce (Picea mariana)
Bum-Yong Kang, Ishminder K Mann, John E Major, Om P Rajora
BMC Genomics , 2010, DOI: 10.1186/1471-2164-11-515
Abstract: We have developed a near-saturated and complete genetic linkage map of black spruce using a three-generation outbred pedigree and amplified fragment length polymorphism (AFLP), selectively amplified microsatellite polymorphic loci (SAMPL), expressed sequence tag polymorphism (ESTP), and microsatellite (mostly cDNA based) markers. Maternal, paternal, and consensus genetic linkage maps were constructed. The maternal, paternal, and consensus maps in our study consistently coalesced into 12 linkage groups, corresponding to the haploid chromosome number (1n = 1x = 12) of 12 in the genus Picea. The maternal map had 816 and the paternal map 743 markers distributed over 12 linkage groups each. The consensus map consisted of 1,111 markers distributed over 12 linkage groups, and covered almost the entire (> 97%) black spruce genome. The mapped markers included 809 AFLPs, 255 SAMPL, 42 microsatellites, and 5 ESTPs. Total estimated length of the genetic map was 1,770 cM, with an average of one marker every 1.6 cM. The maternal, paternal and consensus genetic maps aligned almost perfectly.We have constructed the first high density to near-saturated genetic linkage map of black spruce, with greater than 97% genome coverage. Also, this is the first genetic map based on a three-generation outbred pedigree in the genus Picea. The genome length in P. mariana is likely to be about 1,800 cM. The genetic maps developed in our study can serve as a reference map for various genomics studies and applications in Picea and Pinaceae.Genetic maps provide an important genomic resource for understanding genome organization and evolution, comparative genomics, mapping genes and quantitative trait loci, and associating genes and genomic segments with phenotypic traits, especially in those species whose genomes are not yet completely sequenced. For understanding the genetic architecture of species, genetic maps with high levels of genome coverage and confidence in the marker order are required. Hig
Leaf Area and Structural Changes after Thinning in Even-Aged Picea rubens and Abies balsamea Stands in Maine, USA  [PDF]
R. Justin DeRose,Robert S. Seymour
International Journal of Forestry Research , 2012, DOI: 10.1155/2012/181057
Abstract: We tested the hypothesis that changes in leaf area index (LAI?m2?m?2) and mean stand diameter following thinning are due to thinning type and residual density. The ratios of pre- to postthinning diameter and LAI were used to assess structural changes between replicated crown, dominant, and low thinning treatments to 33% and 50% residual density in even-aged Picea rubens and Abies balsamea stands with and without a precommercial thinning history in Maine, USA. Diameter ratios varied predictably by thinning type: low thinnings were <0.7, crown thinnings were >0.7 but <1.0, and dominant thinnings were >1.0 . LAI change was affected by type and intensity of thinning. On average, 33% density reduction removed <50% of LAI, whereas 50% density reduction removed >50% of LAI. Overall reduction of LAI was generally greatest in dominant thinnings (54%), intermediate in crown thinnings (46%), and lowest in low thinnings (35%). Upon closer examination by crown classes, the postthinning distribution of LAI between upper and lower crown classes varied by thinning history, thinning method, and amount of density reduction. 1. Introduction Leaf area index (LAI m2?m?2) is an important factor determining both tree and stand level production [1]. While LAI is biologically important due to the fact that foliage is where photosynthesis occurs [2], it is also arguably the most appropriate descriptor of growing space occupancy whether one is characterizing simple-structured, single-species forests [3, 4] or complex-structured, multispecies forests [5–7]. This importance is due to the strong well-established relationship between LAI and volume increment for both individual trees [8–11] and stands [12–14]. Accordingly, leaf area-based stocking models that incorporate these relationships have been developed as tools [6, 7, 15] giving managers the ability to base silvicultural retention on individual tree growth capability as opposed to simply diameter (DBH), although implementation is aided by taking advantage of the observed relationships between individual tree DBH and leaf area [9]. Given that LAI describes growing space occupancy and productivity, quantification of its relationship to silvicultural activities, for example, intermediate thinning, should be of primary importance. Thinning as a means to increase stand-level production, or more specifically the growth of some predetermined individuals, is an important part of silviculture [16]. Though we understand thinning does not increase overall growth per se , it can redirect the efficient use of growing space (i.e., LAI) to
Structural Elucidation of Condensed Tannin from Picea mariana Bark  [PDF]
Papa Niokhor Diouf, Carmen Mihaela Tibirna, Martha-Estrella García-Pérez, Mariana Royer, Pascal Dubé, Tatjana Stevanovic
Journal of Biomaterials and Nanobiotechnology (JBNB) , 2013, DOI: 10.4236/jbnb.2013.43A001
Abstract:

The aim of this work was to determine the structural characteristics of the condensed tannins isolated from the aqueous extract of black spruce (Picea mariana Mill) bark. This is the first report on the structural characterization of condensed tannins from black spruce bark. The condensed tannins from the hot water extract prepared from Picea mariana bark were isolated by column chromatography on Sephadex LH-20 media. In this study, UV-visible and 13C-NMR spectroscopic techniques, along with pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) and liquid chromatogramphy analyses were applied to determine the structural characteristics of black spruce bark tannins. We have confirmed for the first time the presence of methoxylated B-rings in the flavanol units of condensed tannins from black spruce bark, which could be regarded as further contribution to the chemotaxonomy of the genus Picea. The methoxylation of Norway spruce bark condensed tannins have been demonstrated previously.

Root endophyte and mycorrhizosphere fungi of black spruce, Picea mariana, in a boreal forest habitat: influence of site factors on fungal distributions
Richard C. Summerbell
Studies in Mycology , 2005,
Abstract: In a study of fungi growing in various root-associated habitats in and around Picea mariana, black spruce, in northern Ontario, Canada, an examination was made of the degree to which differences in growth sites within an area of a few square kilometers might influence the structure of root-associated filamentous microfungal populations. Picea mariana roots were collected at four strongly differing boreal forest sites: an undisturbed forest site with deep litter and humus layers; a recently regenerated forest; a clearcut, former portable sawmill site with a few small, naturally regenerated trees; and an open peat bog penetrated by roots from trees growing along the margin. Comparisons were done on isolate assemblages primarily from serially washed mycorrhizae, supplemented with comparison samples from washed root bark and adherent rhizosphere soil. The Bray & Curtis similarity index and nodal components analysis were utilised to identify trends within the data. Root endophyte fungi, mainly Phialocephala fortinii and Meliniomyces variabilis, were among the most common isolates from serially washed mycorrhizae and showed strong trends among the site types, with the former most common from sites low in humus and also low in known humus-associated microfungi, and the latter most common from the peat bog site. The overall composition of the isolate assemblages from washed mycorrhizae mainly reflected site factors, with assemblages from the undisturbed and regenerated forest sites similar to one another and those from the clearcut and peat bog sites strongly distinct. A major difference was also seen between two seasonal samples at the exposed clearcut site, but few seasonal differences were seen at the other sites. The regenerated and undisturbed forest sites were high in Umbelopsis isabellina, Mortierella verticillata and Penicillium spinulosum, fungi typical of humic horizons in boreal podzols; the clearcut yielded the greatest numbers of Fusarium proliferatum, Umbelopsis nana and Penicillium montanense isolates, an assemblage tending to indicate exposed mineral soil; while the peat bog was typified by the presence of characteristic northern peat inhabitants Mortierella pulchella and P. spinulosum, as well as temperate peat inhabitant Penicillium lividum. A synthesis of these results with other data suggests that as a microhabitat, the mycorrhizosphere, as originally defined by Foster & Marks, is of little significance in determining the structure of filamentous fungal populations in soil influenced by the presence of ectomycorrhizal forest tree roots. Edap
Genetic diversity as assessed by ISSR markers in Blackgram (Vigna mungo (L.) Hepper)
Kanimozhi M,Jayamani P,Nadarajan N
Electronic Journal of Plant Breeding , 2009,
Abstract: An investigation was carried out on a collection of 23 blackgram genotypes involving 16 releasedvarieties, six pre release cultures and one wild species Vigna mungo var. silvestris to study the genetic diversityusing twelve ISSR primers. The number of alleles produced by different ISSR primers ranged from eight to 17with an average of 11.5 per primer and the level of polymorphism was found to be 82.05 percent. Similaritymeasures and clustering analyses were made using ISSR data. The resulting dendrogram distributed the 23blackgram genotypes into five main clusters. The highest genetic similarity coefficient was measured betweengenotypes CBG 671 and CBG 632. The results of PCoA were comparable to that of grouping based on UPGMAand 23 genotypes were grouped into four groups. Genotype Vigna mungo var. silvestris was placed separatelyfrom rest of the genotypes in both the analyses. Grouping of varieties using ISSR markers did not show anyrelevance to their pedigree. All the pre release cultures in one group revealed that only a portion of geneticvariation has been exploited. The results revealed that, genetic diversity is low among the varieties releasedfrom the respective institute and hence genotypes were grouped according to the research institutes from whichthey released. It suggests that the research institutes have to enlarge the genetic base for variety development.
The Relative Importance of Nitrogen vs. Moisture Stress May Drive Intraspecific Variations in the SLA-RGR Relationship: The Case of Picea mariana Seedlings  [PDF]
Philippe LeBel, Robert L. Bradley, Nelson Thiffault
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.46158
Abstract:

Plants acclimate to nitrogen (N) or moisture stress by respectively increasing photosynthetic N use efficiency (PNUE) or water use efficiency (WUE), in order to maximize their relative growth rate (RGR). These two phenotypic adaptations have opposite effects on specific leaf area (SLA). Thus, intraspecific variations in the SLA-RGR relationship should reflect the relative importance of N vs. moisture stress in plants. In this study, we measured needle gas exchanges and N concentrations in order to derive PNUE and WUE, as well as SLA and RGR of black spruce (Picea mariana) seedlings growing on a rapidly drained site in the presence or absence of Kalmia angustifolia. The eradication of Kalmia had resulted in a ~140% increase in seedling growth over a 6 year period. We found a negative SLA-RGR relationship where Kalmia had been eradicated, and a positive one where Kalmia had been maintained. Kalmia eradication resulted in higher WUE when measurements were made directly on the seedlings, and in lower PNUE when twigs were rehydrated prior to gas exchange measurements. Our data suggest that the bigger seedlings on Kalmia-eradicated plots increase RGR by decreasing SLA, as a means of coping with moisture stress. By contrast, increasing SLA on noneradicated plots may be a means of coping with nutrient stress exerted by Kalmia. The SLA-RGR

Genetic Diversity in Spring Wheat Landraces from Northwest of Iran Assessed by ISSR Markers  [cached]
Omid SOFALIAN,Nader CHAPARZADEH,Meysam DOLATI
Notulae Botanicae Horti Agrobotanici Cluj-Napoca , 2009,
Abstract: Inter Simple Sequence Repeat (ISSR) markers were used to study the genetic diversity of 18 spring growth type landraces from Iran and selected 9 cultivars grown in Iran out of 15 ISSR primers .11 primers were found to have enough polymorphism and they were used for assessment. These primers are composed of di, tetra and penta-nucleotide sequences. From a total of 108 DNA fragments produced, 78 (72.22%) fragments were polymorphic. The UPGMA clustering algorithm classified the varieties into three major groups .Majority of landraces located in each group were originated from common locations. The results revealed that ISSR markers could be efficiently used to evaluate genetic variation in the wheat germplasm. Genetic similarity and dissimilarities among genotypes will be useful for genetic differentiation of wheat accessions, selection strategies and genetic development of crop plants.
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