scholarly journals Mapping of QTLs related with wood quality and developmental characteristics in hybrids (Eucalyptus grandis x Eucalyptus urophylla)

2007 ◽  
Vol 31 (1) ◽  
pp. 13-24 ◽  
Author(s):  
Rodrigo Barros Rocha ◽  
Everaldo Gonçalves Barros ◽  
Cosme Damião Cruz ◽  
Antônio Marcos Rosado ◽  
Elza Fernandes de Araújo
Keyword(s):  
Molecular Markers ◽  
Composite Interval Mapping ◽  
Growth Traits ◽  
Wood Quality ◽  
Eucalyptus Grandis ◽  
Phenotypic Selection ◽  
Interval Mapping ◽  
Molecular Data ◽  
Early Selection ◽  
Pulp Yield

The present work aimed to characterize and identify QTLs for wood quality and growth traits in E. grandis x E. urophylla hybrids. For this purpose a RAPD linkage map was developed for the hybrids (LOD=3 and r=0.40) containing 52 markers and 12 linkage groups. Traits related to wood quality and growth were evaluated in the QTL analyses. QTL analyses were performed using chi-square tests, single-marker, interval mapping and composite interval mapping analyses. All approaches led to the identification of similar QTLs associated with wood density, cellulose pulp yield and percentage of extractives, which were detected and confirmed by both the interval mapping and composite interval mapping methodologies. Some QTLs regions were confirmed only by the composite interval mapping methodology: percentage of soluble lignin, percentage of insoluble lignin, CBH and total height. Overlapping QTLs regions were detected, and these, can be the result of major genes involved in the regulation and control of the growth traits by epistatic interactions. In order to evaluate the effect of early selection using RAPD molecular data, molecular markers adjacent to QTLs were used genotype selection. The analysis of selection differential values suggests that for all the traits the phenotypic selection at seven years should generate larger genetic gains than early selection assisted by molecular markers and the combination of the strategies should elevate the selection efficiency.

Defoliation by insects reduces the wood quality and cellulosic pulp production

Holzforschung ◽  
2020 ◽  
Vol 74 (5) ◽  
pp. 489-495
Author(s):  
Antonio José Vinha Zanuncio ◽  
Amélia Guimarães Carvalho ◽  
Mariane Bueno de Camargo ◽  
Flaviana Reis Milagres ◽  
Vinícius Resende de Castro ◽  
...  
Keyword(s):  
Wood Quality ◽  
Eucalyptus Grandis ◽  
Basic Density ◽  
Pulp Yield ◽  
Extractive Content ◽  
Eucalyptus Saligna ◽  
Wood Volume ◽  
Cellulosic Pulp ◽  
G Ratio ◽  
Pulp Production

AbstractDefoliating insects damage forest plantations, but the estimation of their losses does not take into account wood quality changes. The objective was to evaluate the wood quality and pulp production of two clones of Eucalyptus grandis × Eucalyptus urophylla (clone A) and Eucalyptus saligna (clone B) damaged or not by defoliating insects. Five healthy trees and five attacked by Gonipterus platensis Marelli (Coleoptera: Curculionidae) were selected per clone. The wood volume per hectare in the affected settlements was at least 9% lower and damaged trees showed lower wood basic density, with at least 4.6%. The lignin and extractive content in the wood increased by at least 5.6 and 45%, respectively, while the syringyl/guaiacyl (S/G) ratio remained constant for clone A and increased 10% for clone B. For pulps, an increased effective alkali and decreased pulp yield were experienced for both clones while bleaching or pulp quality was not affected. In the stands affected by defoliating insects, productivity was 9 and 19% lower considering the wood volume per hectare and 15 and 24% considering the cellulose pulp production per hectare, respectively.

scholarly journals Time-Related Mapping of Quantitative Trait Loci Underlying Tiller Number in Rice

Genetics ◽  
1999 ◽  
Vol 151 (1) ◽  
pp. 297-303 ◽  
Author(s):  
Wei-Ren Wu ◽  
Wei-Ming Li ◽  
Ding-Zhong Tang ◽  
Hao-Ran Lu ◽  
A J Worland
Keyword(s):  
Quantitative Trait Loci ◽  
Quantitative Trait ◽  
Composite Interval Mapping ◽  
Interval Mapping ◽  
Tiller Number ◽  
Multiple Trait ◽  
Phenotypic Data ◽  
Recombinant Inbred Population ◽  
Trait Loci ◽  
Final Observation

Abstract Using time-related phenotypic data, methods of composite interval mapping and multiple-trait composite interval mapping based on least squares were applied to map quantitative trait loci (QTL) underlying the development of tiller number in rice. A recombinant inbred population and a corresponding saturated molecular marker linkage map were constructed for the study. Tiller number was recorded every 4 or 5 days for a total of seven times starting at 20 days after sowing. Five QTL were detected on chromosomes 1, 3, and 5. These QTL explained more than half of the genetic variance at the final observation. All the QTL displayed an S-shaped expression curve. Three QTL reached their highest expression rates during active tillering stage, while the other two QTL achieved this either before or after the active tillering stage.

Bayesian Mapping of Multiple Quantitative Trait Loci From Incomplete Inbred Line Cross Data

Genetics ◽  
1998 ◽  
Vol 148 (3) ◽  
pp. 1373-1388
Author(s):  
Mikko J Sillanpää ◽  
Elja Arjas
Keyword(s):  
Quantitative Trait Loci ◽  
Quantitative Trait ◽  
Composite Interval Mapping ◽  
Backcross Progeny ◽  
Random Variable ◽  
Interval Mapping ◽  
Mapping Method ◽  
Structure Mapping ◽  
Standard Interval ◽  
Trait Loci

Abstract A novel fine structure mapping method for quantitative traits is presented. It is based on Bayesian modeling and inference, treating the number of quantitative trait loci (QTLs) as an unobserved random variable and using ideas similar to composite interval mapping to account for the effects of QTLs in other chromosomes. The method is introduced for inbred lines and it can be applied also in situations involving frequent missing genotypes. We propose that two new probabilistic measures be used to summarize the results from the statistical analysis: (1) the (posterior) QTL-intensity, for estimating the number of QTLs in a chromosome and for localizing them into some particular chromosomal regions, and (2) the location wise (posterior) distributions of the phenotypic effects of the QTLs. Both these measures will be viewed as functions of the putative QTL locus, over the marker range in the linkage group. The method is tested and compared with standard interval and composite interval mapping techniques by using simulated backcross progeny data. It is implemented as a software package. Its initial version is freely available for research purposes under the name Multimapper at URL http://www.rni.helsinki.fi/~mjs.

scholarly journals Non-Destructive Assessment of Wood Stiffness in Scots Pine (Pinus sylvestris L.) and its Use in Forest Tree Improvement

Forests ◽  
2019 ◽  
Vol 10 (6) ◽  
pp. 491 ◽  
Author(s):  
Irena Fundova ◽  
Tomas Funda ◽  
Harry X. Wu
Keyword(s):  
Scots Pine ◽  
Growth Traits ◽  
Wood Quality ◽  
Genetic Correlations ◽  
Forest Tree ◽  
Wood Stiffness ◽  
Standing Trees ◽  
Genetic And Phenotypic Correlations ◽  
Sib Families ◽  
Using Data

Wood stiffness is an important wood mechanical property that predetermines the suitability of sawn timber for construction purposes. Negative genetic correlations between wood stiffness and growth traits have, however, been reported for many conifer species including Scots pine. It is, therefore, important that breeding programs consider wood stiffness and growth traits simultaneously. The study aims to (1) evaluate different approaches of calculating the dynamic modulus of elasticity (MOE, non-destructively assessed stiffness) using data from X-ray analysis (SilviScan) as a benchmark, (2) estimate genetic parameters, and (3) apply index selection. In total, we non-destructively measured 622 standing trees from 175 full-sib families for acoustic velocity (VEL) using Hitman and for wood density (DEN) using Resistograph and Pilodyn. We combined VEL with different wood densities, raw (DENRES) and adjusted (DENRES.TB) Resistograph density, Pilodyn density measured with (DENPIL) and without bark (DENPIL.B), constant of 1000 kg·m−3 (DENCONST), and SilviScan density (DENSILV), to calculate MOEs and compare them with the benchmark SilviScan MOE (MOESILV). We also derived Smith–Hazel indices for simultaneous improvement of stem diameter (DBH) and wood stiffness. The highest additive genetic and phenotypic correlations of the benchmark MOESILV with the alternative MOE measures (tested) were attained by MOEDENSILV (0.95 and 0.75, respectively) and were closely followed by MOEDENRES.TB (0.91 and 0.70, respectively) and MOEDENCONST and VEL (0.91 and 0.65, respectively for both). Correlations with MOEDENPIL, MOEDENPIL.B, and MOEDENRES were lower. Narrow-sense heritabilities were moderate, ranging from 0.39 (MOESILV) to 0.46 (MOEDENSILV). All indices revealed an opportunity for joint improvement of DBH and MOE. Conclusions: MOEDENRES.TB appears to be the most efficient approach for indirect selection for wood stiffness in Scots pine, although VEL alone and MOEDENCONST have provided very good results too. An index combining DBH and MOEDENRES.TB seems to offer the best compromise for simultaneous improvement of growth, fiber, and wood quality traits.

scholarly journals Development of EST-Molecular Markers from RNA Sequencing for Genetic Management and Identification of Growth Traits in Potato Grouper (Epinephelus tukula)

Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 36
Author(s):  
Te-Hua Hsu ◽  
Yu-Ting Chiu ◽  
Hung-Tai Lee ◽  
Hong-Yi Gong ◽  
Chang-Wen Huang
Keyword(s):  
Molecular Markers ◽  
Expressed Sequence Tag ◽  
De Novo ◽  
Growth Traits ◽  
Gene Diversity ◽  
Snp Markers ◽  
Cdna Libraries ◽  
Functional Markers ◽  
Genetic Management ◽  
Ssr And Snp Markers

The accuracy and efficiency of marker-assisted selection (MAS) has been proven for economically critical aquaculture species. The potato grouper (Epinephelus tukula), a novel cultured grouper species in Taiwan, shows large potential in aquaculture because of its fast growth rate among other groupers. Because of the lack of genetic information for the potato grouper, the first transcriptome and expressed sequence tag (EST)-derived simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers were developed. Initially, the transcriptome was obtained from seven cDNA libraries by using the Illumina platform. De novo transcriptome of the potato grouper yielded 51.34 Gb and 111,490 unigenes. The EST-derived SSR and SNP markers were applied in genetic management, in parentage analysis, and to discover the functional markers of economic traits. The F1 juveniles were identified as siblings from one pair of parents (80 broodstocks). Fast- and slow-growth individuals were analyzed using functional molecular markers and through their association with growth performance. The results revealed that two SNPs were correlated with growth traits. The transcriptome database obtained in this study and its derived SSR and SNP markers may be applied not only for MAS but also to maintain functional gene diversity in the novel cultured grouper.

PHENOTYPIC SELECTION ASSISTED BY MOLECULAR MARKERS FOR SCAB RESISTANCE IN APPLE

2009 ◽  
pp. 771-776
Author(s):  
C. Botez ◽  
R. Sestras ◽  
M. Ardelean ◽  
D. Pamfil ◽  
B. Patrascu ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Phenotypic Selection ◽  
Scab Resistance

scholarly journals Efficiency of early selection for rotation-aged wood quality traits in radiata pine

2007 ◽  
Vol 64 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Harry X. Wu ◽  
Mike B. Powell ◽  
Junli L. Yang ◽  
Milo Ivković ◽  
Tony A. McRae
Keyword(s):  
Wood Quality ◽  
Radiata Pine ◽  
Early Selection ◽  
Quality Traits ◽  
Selection For

scholarly journals Molecular characterization and distribution of Plasmodium matutinum, a common avian malaria parasite

Parasitology ◽  
2017 ◽  
Vol 144 (13) ◽  
pp. 1726-1735 ◽  
Author(s):  
GEDIMINAS VALKIŪNAS ◽  
MIKAS ILGŪNAS ◽  
DOVILĖ BUKAUSKAITĖ ◽  
VAIDAS PALINAUSKAS ◽  
RASA BERNOTIENĖ ◽  
...  
Keyword(s):  
Molecular Markers ◽  
Molecular Characterization ◽  
Malaria Parasite ◽  
Avian Malaria ◽  
Clinical Signs ◽  
Molecular Data ◽  
Infected Blood ◽  
Avian Malaria Parasite ◽  
Thrush Nightingale

SUMMARYSpecies of Plasmodium (Plasmodiidae, Haemosporida) are widespread and cause malaria, which can be severe in avian hosts. Molecular markers are essential to detect and identify parasites, but still absent for many avian malaria and related haemosporidian species. Here, we provide first molecular characterization of Plasmodium matutinum, a common agent of avian malaria. This parasite was isolated from a naturally infected thrush nightingale Luscinia luscinia (Muscicapidae). Fragments of mitochondrial, apicoplast and nuclear genomes were obtained. Domestic canaries Serinus canaria were susceptible after inoculation of infected blood, and the long-lasting light parasitemia developed in two exposed birds. Clinical signs of illness were not reported. Illustrations of blood stages of P. matutinum (pLINN1) are given, and phylogenetic analysis identified the closely related avian Plasmodium species. The phylogeny based on partial cytochrome b (cyt b) sequences suggests that this parasite is most closely related to Plasmodium tejerai (cyt b lineage pSPMAG01), a common malaria parasite of American birds. Both these parasites belong to subgenus Haemamoeba, and their blood stages are similar morphologically, particularly due to marked vacuolization of the cytoplasm in growing erythrocytic meronts. Molecular data show that transmission of P. matutinum (pLINN1) occurs broadly in the Holarctic, and the parasite likely is of cosmopolitan distribution. Passeriform birds and Culex mosquitoes are common hosts. This study provides first molecular markers for detection of P. matutinum.

Variable expression of molecular markers in juvenile nasopharyngeal angiofibroma

2017 ◽  
Vol 131 (9) ◽  
pp. 752-759 ◽  
Author(s):  
A Mishra ◽  
A Pandey ◽  
S C Mishra
Keyword(s):  
Molecular Markers ◽  
Clinical Characteristics ◽  
Indian Population ◽  
Molecular Data ◽  
Juvenile Nasopharyngeal Angiofibroma ◽  
Molecular Characteristics ◽  
Nasopharyngeal Angiofibroma ◽  
Variable Expression ◽  
Geographical Bias ◽  
Research Questions

AbstractBackground:Molecular categorisation may explain the wide variation in the clinical characteristics of juvenile nasopharyngeal angiofibroma.Methods:Variations in molecular markers in juvenile nasopharyngeal angiofibroma in an Indian population were investigated and compared with global reports.Results:Variable molecular marker expression was demonstrated at the regional and global levels. A wide variation in molecular characteristics is evident. Molecular data have been reported for only 11 countries, indicating a clear geographical bias. Only 58 markers have been studied, and most are yet to be validated.Conclusion:Research into the molecular epidemiology of juvenile nasopharyngeal angiofibroma is still in its infancy. Although the molecular variation is not well understood, data obtained so far have prompted important research questions. Hence, multicentre collaborative molecular studies are needed to establish the aetiopathogenesis and establish molecular surrogates for clinical characteristics.

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