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Induction of Quercus ilex L. haploid and doubled-haploid embryos from anther cultures by temperature-stress

embryos detected by enzyme and RAPD gene markers. Int J Plant Sci 161: 363-367. DOI: 10.1086/314265 BUENO, M. A., A. GÓMEZ, F. SEPULVEDA, J. M. SEGUÍ, P. S. TESTILLANO, J. A. MANZANERA and M. C. RISUEÑO (2003): Microspore-derived from Quercus suber anthers mimic zygotic embryos and maintain haploidy in long-term anther culture. J Plant Physiol 160: 953-960. BUENO, M. A., B. PIONTOS, M. J. PRADO, A. GÓMEZ and J. A. MANZANERA (2004): Androgenesis: A tool for woody plant breeding, pp. 365-383 Vol 1. Part II in Recent Research Developments

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Heritabilities, Intertrait Genetic Correlations, G x E Interaction and Predicted Genetic Gains for Acoustic Velocity in Mid-rotation Coastal Douglas fir

–64. S ilen , R. and J. W heat (1979): Progressive tree improvement program in coastal Douglas-fir. J. Forestry 44 : 78–83. T oulmin , M. J. and C. A. R aymond (2007): Developing a sampling strategy for measuring acoustic velocity in standing Pinus radiata using the TreeTap time of flight tool. New Zealand Journal of Forestry Science 37 : 96–111. V an W yk , G. V. (1990): Genetic improvement of timber yield and wood quality in Eucalyptus grandis (Hill) Maiden. Part 1. Genetic parameters of growth characteristics. South African Forestry Journal 153

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Occurrence and cytological mechanism of numerically unreduced pollen in diploid Populus euphratica

. BARCACCIA, E. ALBERTINI and F. VERONESI (2000): Mapping the jp (jumbo pollen) gene and QTLs involved in multinucleate microspore formation in diploid alfalfa. Theor Appl Genet 101: 372-378. VAN TUYL, J. and K. LIM (2003): Interspecific hybridization and polyploidisation as tools in ornamental plant breeding. Acta Hortic 612: 13-22. VEILLEUX, R. (1985): Diploid and polyploid gametes in crop plants: Mechanisms of formation and utilization in plant breeding. Plant Breed Rev 3: 253-288. VEILLEUX, R., N. MCHALE and F. LAUER (1982

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Comparing Morphological With Genetic Distances Between Populations: A New Method and its Application to the Prosopis chilensis – P. flexuosa complex

Abstract

The biological units that are the object of management, preservation and improvement for the development of sustainable productive systems in natural areas, need to be differentiated and analyzed. Attending to this need, a new morphological distance is presented in this work. This distance is based on qualitative criteria and is applied to numerical taxonomy studies. The characteristics of this trait allow its comparison with the genetic distance of GREGORIUS (1974). Both parameters are essential tools in basic studies of native species populations. The morphological distance is applied to reveal genetically differentiated units in a swarm of hybrids between closely related species, and this result is compared with the results obtained from the application of traditional methods of numerical taxonomy.

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A Comparison of Isozyme and Morphological Markers to Assess the Within Population Variation in Small Populations of European aspen (Populus tremula L.) in Spain

Summary

European aspen (Populus tremula L.) has been traditionally thought to establish new stands by vegetative propagation through root suckers produced by very few individuals (often only one). Morphological traits and isozyme patterns were studied in five small stands in northern Spain. Both isozyme and morphological approaches showed variation within and between stands. Estimated intrapopulational variation was higher than the expected, and clusters of individuals with the same isozyme multilocus patterns within each population have been identified. In order to check to what extent morphological markers are affected by the genotypes or clones, comparisons between leaf parameters and isozyme patterns were performed by hierarchical ANOVA and tests of hypothesis were constructed from the components of variance. Leaf shape parameters show a good correlation with the isozyme multilocus patterns. On the other hand, leaf size parameters, were more influenced by environmental factors. These traits may be useful as tools for the definition of in situ conservation units in endangered European aspen stands.

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Characterization of a Suite of 40 EST-derived Microsatellite Markers For Use in Sitka Spruce (Picea sitchensis (Bong.) Carr)

Abstract

This paper describes 40 novel, data-mined, polymorphic microsatellite loci for use in a QTL association study in Sitka spruce. Publicly available EST sequences of Picea in Genbank were searched in silico for simple sequence repeat (SSR) motifs, principally dinucleotide microsatellites, and PCR primers were designed to flank these regions. PCR amplification was carried out in the progeny of a full-sib family to test simple Mendelian inheritance. For further characterization, the amplification products of Sitka spruce material from unrelated trees were assessed to determine the potential of these loci for population genetic studies. These polymorphic markers therefore represent a valuable tool-kit both for establishing a molecular map of this species and for Picea genetic population studies.

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Sampling Tissue for DNA Analysis of Trees: Trunk Cambium as an Alternative to Canopy Leaves

Abstract

The number of studies of tropical tree species that use molecular tools is increasing, most of which collect leaf tissue for genomic DNA extraction. In tropical trees the canopy is not only frequently inaccessible, but also, once reached, the leaf tissue is often heavily defended against herbivory by high concentrations of anti-predation compounds, which may inhibit downstream applications, particularly PCR. Cambium tissue, accessed directly from the tree trunk at ground level, offers a readily accessible resource that is less hampered by the presence of defensive chemicals than leaf tissue. Here we describe a simple method for obtaining tissue from the cambial zone for DNA extraction and test the applicability of the method in a range of tropical tree species. The method was used successfully to extract DNA from 11 species in nine families. A subset of the DNA extracts was tested in more detail and proved to be highly suitable for AFLP analysis.

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Early Assessment of First Year Height Data from Five Acacia mearnsii (black wattle) Sub-populations in South Africa using REML/BLUP

Abstract

Recent research has shown, Acacia mearnsii (black wattle) to be a source of high quality pulp. This led to a change in the emphasis in the breeding programme at the Institute for Commercial Forestry Research, from improving bark yield and quality, to improving timber yield and quality while maintaining an acceptable bark quality. A Multiple Population Breeding Strategy was implemented to cater for these changes. Five sub-populations were established across different sites in KwaZulu- Natal and were determined by origin of seed. Each sub-population was established as a progeny trial with a seedling seed orchard adjacent to it. The management of the seed orchards will be determined according to the performance of the families within the progeny trials. This paper reports on the first year height measurements taken from the five sub-populations. The intention of this paper is not to base any selections from this data but rather to establish a set of analyses using REML/BLUP which will be used for future data analysis. This will also allow for future assessment of age-age correlations for the various traits being assessed and provide an appropriate decision-making tool, for selecting individuals for future generations.

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Genetic parameters for early growth and biomass traits of Pinus radiata D. Don under different water regimes

Abstract

In Chile, genetic improvement of Radiata pine has been directed towards characters such as volume, form and wood density. Estimation of genetic parameters for growth and biomass traits in young seedlings, as a tool for early indirect selection in the P. radiata breeding program, has not been explored yet. We aimed to estimate genetic parameters for growth and biomass traits. Five-month-old P. radiata seedlings grown under wellwatered (WW) and water stress (WS) regimes were evaluated. Root collar diameter, height, shoot dry weight, root dry weight, total dry weight, height/diameter ratio and root/shoot ratio were analyzed in both treatments. Trait with the highest heritability was root/shoot ratio in WW and WS regime (h2 = 0.80 and 0.63 respectively). The highest genetic correlation was between height and shoot dry weight (rg = 0.90), under WW regime. In contrast, there were negative genetic correlations between root collar diameter and height/diameter ratio under WS regime. To breed for drought tolerance, traits such as height and root collar diameter would be effective targets for indirect selection since estimated heritabilities are high, there is sizable genetic variation, they are easily assessed, they can be measured non-destructively and they have a high genetic correlation with root/shoot ratio, a trait related to drought tolerance. The measurement of dry weights for early selection purposes is not recommended.

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Chromosome Microdissection, Cloning and Painting of the Chromosome 1 in Poplar (Populus tremula)

Abstract

The chromosome microdissection, cloning and painting technology has evolved into an efficient tool for genomic research. Application of these techniques has rarely been applied for forest plants, largely due to the difficulty of chromosome preparation. The present study was performed to establish a method for single chromosome microdissection, cloning and painting in forest plants using poplar (Populus tremula) as a model. An individual chromosome 1 was microdissected from the metaphase spreads of poplar root-tip cells with fine glass needle controlled by a micromanipulator. The dissected chromosome was amplified in vitro by the Sau3A linker adaptor mediated PCR (LA-PCR) technique, by which 200bp to 3,000bp smear DNA fragments were obtained. Then, the second round PCR products from the single chromosome 1 were cloned into T-easy vectors to generate a DNA library of the chromosome 1. Approximately 3 x 105 recombinant clones were obtained. The second round PCR products were used as a complex probe mixture for fluorescent in situ hybridization (FISH) on the metaphase spreads of poplar. Hybridization signals were observed, mainly, along the entire chromosome 1, at the same time, signals were also present on telomeric and centromeric regions of other chromosomes. Therefore, this research suggests that chromosome microdissection, cloning and painting of the single small chromosome in forest plants are feasible.

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