Concepción, Chile
Concepción, Chile

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Density variation, being the timber longitudinally measured, and the precision of spectroscopy of near infrared (NIR) were evaluated to predict density and pulp yield in two Eucalyptus globulus clones. Furthermore, variability in volume and in NIR predictions was evaluated in four E. globulus clones represented in two growth sites. Clones were selected by means of two trials: 10 and 11 year old clones in two sites from Araucanía Region, Chile. From each selected ramet, shavings samples at breast height diameter (BHD) were obtained to NIR predictions. Additionally, of a subgroup of ramets, chips samples from all the timber and six disks BHD, 20%, 40%, 60%, 80% and 100% of commercial height were obtained. NIR predictions were contrasted with values obtained for chips and disks by means of standard error of prediction (SEP) and bias. Variance analyses of two factors (clones and sites) and correlation analyses were used. Density showed an increase from the base to the apex in both clones, though with a different variation profile; consequently, clones presented a different mean density, nonetheless their BHD was similar. NIR predictions showed an error inside the rank given for E. globulus, being those from pulp yield especially exact. Concerning volume, density and pulp yield showed low variability, both among clones and response to the site as well.

Pinus radiata is a conifer of recognized economic value. Studies at genetic and molecular level to support breeding programs of radiata pine have been conducted with difficulty due to its large and complex genome. The development of molecular markers has allowed performing studies on genetic variation, identification of clones and construction of linkage maps. In order to increase the genetic molecular markers in P. radiata, two inter simple sequence repeat (ISSR) markers and twelve selective amplifications of microsatellite polymorphic loci (SAMPL) primer combinations were tested, using a first-generation full-sib family of 86 individuals. Polymerase chain reaction (PCR) products were visualized by capillary electrophoresis and polymorphism was detected by presence or absence of a particular fragment in one P. radiata parental. A total of 18 polymorphic fragments were found for two ISSR primers tested, with an average segregation distortion of 33%. SAMPL markers yielded 85 polymorphic fragments with eight primer combinations, with an average of 22.3% segregation distortion. Both methodologies showed a good reproducibility, with easy implementation and useful for genetic analysis on P. radiata.

Ananias R.A.,University of Bío Bío | Lastra J.,University of Bío Bío | Salvo L.,University of Bío Bío | Contreras H.,University of Bío Bío | And 2 more authors.
Maderas: Ciencia y Tecnologia | Year: 2010

Radial and apical variation in resin canals of radiata pine were studied. The frequency and size of resin canals were examined, using microscopic techniques from a commercial software. Wood samples from standing trees were taken, showing three different levels of external resin-bleeding intensity: moderate, light and intense. The variability of the resin canals were examined according to the radial position at three different heights; bottom, breast height diameter and at the beginning of the tree top. The results show that the apical and radial variation of the size and frequency of resin canals appeared weakly correlated with the intensity level of the tree resin-bleeding of the standing radiata pine trees.

Moraga-Suazo P.,University of Concepción | Orellana L.,University of Concepción | Quiroga P.,University of Concepción | Balocchi C.,BIOFOREST | And 4 more authors.
Trees - Structure and Function | Year: 2014

Key message: The heritability of genetic resistance of radiata pine against Fusarium circinatum was not clear. We demonstrated that there are at least 3 QTLs that could be involved in this resistance/susceptibility.Abstract: A genetic linkage map was developed for Pinus radiata, using Amplified Fragment Length Polymorphism (AFLP), Inter-Simple Sequence Repeat (ISSR), Selective Amplification of Microsatellite Polymorphic Loci (SAMPL), and Simple Sequence Repeat (SSR) molecular markers, based on a two-way pseudo-testcross strategy, using 86 individuals of a F1 full-sib family and 787 molecular markers for genotyping. Linkage analysis generated a map of medium to high density for each parent, with 1,060 and 1,258 cM for parents XO and XP, respectively. A total of 458 markers were mapped on 12 linkage groups (LG) in XO and XP, which equals the number of haploid chromosomes present in P. radiata. Analysis of quantitative trait loci (QTL) for resistance against pitch canker disease caused by Fusarium circinatum was made using Bayesian Information Criterion (BIC). In the XO parental map, two groups (LG-1 and LG-9) showed high probabilities for one or more QTLs. Only one group (LG-9) in the XP parental map showed probability for one or more QTLs. The results indicate that resistance to pitch canker is inherited from both parents. These results provide the basis for further studies focused on structure, evolution, and function of the P. radiata genome. © 2014, Springer-Verlag Berlin Heidelberg.

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