bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors Influencing Male Reproductive Success in a Cryptomeria japonica Seed Orchard Revealed by Microsatellite Marker Analysis
Authors: Moriguchi Y. , Tsuchiya S. , Iwata H. , Itoo S. , Tani N. , Taira H. , Tsumura Y. 
Published: October 2017

Abstract
We investigated the influence of male flower production, floral synchrony and inter-tree distances on male reproductive success in a miniature seed orchard of Cryptomeria japonica. We used six microsatellite markers to determine the paternity of each seed. In the seed orchard, the average pollen contamination and clonal self-fertilization rates were 38.7% and 1.7%, respectively. The level of male reproductive success of constituent clones varied from 0.0 to 15.7%. Five clones showing the highest male reproductive success contributed ca. 30% of all analyzed seeds as a pollen donor after excluding contamination by external sources of pollen. The statistical analyses showed that male reproductive success was strongly influenced by male flower production of each clone and, possibly, by their distance to the mother trees. The linear regression which included male flower production and floral synchrony as independent variables, however, accounted for only 14.7% of variation of male reproductive success, suggesting that other factors such as pollen competition might also influence male reproductive success. Since we found no significant correlation between male reproductive and female reproductive successes, it may be better to equalize male and female reproductive successes independently
Age-related Trends in Genetic Parameters for Jack Pine and Their Implications for Early Selection
Authors: Weng Y. H. , Tosh K. J. , Park Y. S. , Fullarton M. S. 
Published: October 2017

AbstractTrends in genetic parameters for height growth of jack pine (Pinus banksiana Lamb.) were examined over three series of family tests throughout New Brunswick. Data were analyzed for each site and across sites within each series. Although individual narrow sense heritability estimates from single-site analyses varied substantially from site to site and showed no consistent age-related pattern, the estimates from across-site analyses showed an increasing trend to age 20. Similar as individual narrow sense heritability, the coefficient of additive genetic variance estimated from single site showed more variation than those estimated from across site analyses. Age-age (type-a) genetic correlations for height were high and could be well predicted by a LAR2model, where LAR is the natural logarithm of the ratio between two ages at assessment. Type-b genetic correlations were high and of similar magnitude at different ages. Genetic correlations between height at different ages and volume at one-half rotation age were generally high. Taking the volume at one-half rotation age as the target trait, the selection for target trait from early selection at ages 5~7 could be more efficient per year than direct selection.
Deterministic Simulation of Gains for Seedling and Cloned Main and Elite Breeding Populations of Pinus radiata and Implications for Strategy
Authors: Shelbourne C. J. A. , Kumar S. , Burdon R. D. , Gea L. D. , Dungey H. S. 
Published: October 2017

Abstract
Genetic gains in breast-height diameter were estimated using deterministic simulation. Simulations of gain from one generation of selection were undertaken in large Main and small Elite breeding populations for a range of heritabilities, with varying numbers of parents, families, seedlings/family, clones/family and ramets/ clone to aid revision of the New Zealand Pinus radiata breeding strategy. Cloned versus seedling populations of equal numbers of plants were simulated, derived from open pollination, polycrossing, and pair crossing. Balanced within-family selection was used for 200, 400 and 800-parent Main breeding populations and among- and within-family selection for 25-parent Elite populations of 25 up to 100 full-sib families. Predicted gains from within-family selection in the Main population were highest from cloned polycross families at all heritabilities and lowest for seedling fullsib families. Gains from cloned populations were higher than seedling equivalents at heritabilities ≤0.5, and their advantage in gain was greatest at lower heritabilities. Elite populations of 25 parents showed similar trends but intensive among- and within-family selection resulted in much higher gains than from the Main, highest from the cloned options. The increase in gain with increased number of families diminished with more than 2-3 times as many families as parents. A new strategy was proposed for P. radiata, based on the simulation results, involving an expanded Main breeding population of open-pollinated (OP) seedling families, together with pair-cross family seedlots already available, supported by parentage reconstruction using DNA markers. Forwards selection in small cloned Elite populations was proposed as the main source of seed orchard clones.
Genetic Parameter Estimates for Growth Traits from Diallel Tests of Loblolly Pine Throughout the Southeastern United States
Authors: Mckeand S. E. , Li B. , Grissom J. E. , Isik F. , Jayawickrama K. J. S. 
Published: October 2017

AbstractVariation in heritability and in genetic correlation estimates were evaluated for juvenile tree height and volume for six testing areas of loblolly pine (Pinus taeda L.) in the southeastern United States. Variance components and their functions (heritability and type B genetic correlations) were estimated from 265 six-parent disconnected diallel series, tested in almost 1000 trials (4 tests per diallel series). Original data were collected at age 6 years from about one million trees (265 diallel series x 30 crosses x 36 trees per cross/site x 4 sites) planted in field tests. Genetic tests were from the second cycle of breeding in the North Carolina State University - Industry Cooperative Tree Improvement Program. The overall unbiased individual-tree narrow-sense heritability for height was 0.19 and for volume was 0.16. The broad-sense heritabilities for height (0.24) and for volume (0.22) were higher than narrow-sense heritabilities due to the presence of non-additive genetic variance. There were moderate regional differences in these estimates, with tests in the Lower Gulf Coastal Plain tending to have the highest heritabilities for growth traits. There was very little association between site index and heritability, but heritabilities were higher on sites with the highest survival and highest test precision. Genotype x environment interactions were generally low both for half-sib and full-sib families, indicating that families can be operationally deployed to different sites with little concern about unpredictable performance.
Genetic Variation in Reproductive Traits in a Clonal Seed Orchard of Prunus avium in Northern Spain
Authors: Díaz R. , Merlo E. 
Published: October 2017

AbstractIn the present study we investigated the reproductive phenology of Prunus avium in a seed orchard located in northwestern Spain. The study was carried out with 103 clones from 7 provenance regions in northern Spain. The most advanced flowering stage on different dates and the number of flowers and cherries were monitored over two consecutive years. Significant differences among clones were found for all of the studied traits, with high broad-sense heritability estimates for all, except duration of flowering and synchronization index, both of which showed moderate heritability. In general, there was good overall reproductive synchronization in the seed orchard, although two groups of clones were differentiated. Clones from two out of the seven populations studied flowered later and were less well synchronized. The clonal differentiation was correlated with geoclimatic variables, suggesting that clones from lower altitudes and higher temperatures tend to an earlier flowering.
Strategies for Optimal Deployment of Related Clones into Seed Orchards
Authors: Danusevičius D. , Lindgren D. 
Published: October 2017

Abstract
This study deals with how the deployed proportion of each candidate clone can be decided at the establishment of a seed orchard when the breeding values are available for each candidate in a population of unrelated half-sib families. The following deployment strategies were compared: (a) truncation selection by selecting the clones with the breeding values exceeding certain threshold and deploying equal number of ramets (Truncation strategy); (b) truncation selection by selecting only one best individual within each family (Truncation unrelated); (c) maximizing gain at a given effective clone number (Linear deployment); (d) linear deployment by selecting one best individual within each family (Linear deployment unrelated) and (e) maximizing net gain at a given gene diversity (Optimal proportions). The study focused on the latest alternative and described its superiority and characteristics for a number of possible typical cases. The genetic gain adjusted for predicted inbreeding depression (Net gain), gene diversity and effective clone number were considered as the main ranking criteria. The strategies optimizing the number of related individuals and the linear deployment strategy with restriction on relatedness returned the highest Net gain. If there is a large diversity to select from (the status number of the candidates is more than 8 times greater than the status number desired in the seed orchard), a relatively simple advice is to select the best individual within the best families and deploy the clones linearly according to their breeding values (the number of families selected depends on the desired status number). If the diversity available to select from is small, it seems recommendable to allow half-sibs among the selections and use the Optimal proportions deployment strategy. As the breeding cycles proceed, the status number of the candidate population will decrease and the Optimal proportions strategy is likely to become more favorable.
Mixed Mating With Preferential Outcrossing in Acacia saligna (Labill.) H. Wendl. (Leguminosae: Mimosoideae)
Authors: George N. , Byrne M. , Yan G. 
Published: October 2017

Abstract
Acacia saligna is being developed as an agroforestry crop for the southern agricultural regions of Australia. This study investigated the breeding system of A. saligna to generate basic knowledge for breeding and utilization of the species. Allozyme markers were used to investigate the mating system of four populations of the species. All the populations had high outcrossing rates, with a mean multilocus outcrossing rate of 0.91. The implications of a highly outcrossed mating system to the utilization of A. saligna are discussed.
Genetics of Shrinkage in Juvenile Trees of Pinus radiata D. Don From Two Test Sites in Australia
Authors: Gapare W. J. , Ivković M. , Powell M. B. , McRae T. A. , Wu H. X. 
Published: October 2017

Abstract
To examine the genetic control of wood shrinkage (radial, tangential and longitudinal) in juvenile wood of radiata pine (Pinus radiata D. Don), we assessed samples collected at breast height in two related progeny tests of age 8 and 9 years, established at two different sites in Australia. Green to oven-dry tangential and radial shrinkage for the outer-rings was similar at both sites. Similarly, mean longitudinal shrinkage for the outer-rings was similar at both sites (0.3%, ranging from 0.1 to 1.9 at Flynn and 0.4%, ranging from 0.02 to 1.6, at Kromelite). Mean longitudinal shrinkage for the inner-rings was 4 times greater than that of the outerrings at both sites. The magnitude of the gradient of longitudinal shrinkage from pith to bark (0.001 to 2.9%) is large enough to cause distortion problems including twist and warp, during drying of sawn boards. These values also suggest that shrinkage in the juvenile core of radiata pine is of major economic importance and therefore should be improved either through genetics or silviculture. Individual-tree narrow-sense individual heritability for tangential and radial shrinkage in the outer-rings (4-6) was moderate at Flynn (0.24 ± 0.09 and 0.26±0.07, respectively). There was a lack of significant genetic variation for longitudinal shrinkage in the outer-rings but significant genetic control for the inner-rings (1-2) (h2 = 0.26 ± 0.07). More samples per family are required to detect significant genetic variation for shrinkage traits than other traits due to higher background variation in sampling and measuring shrinkage traits relative to other wood quality traits such as density, microfibril angle (MfA), spiral grain and modulus of elasticity (MoE).
Genetic Variation in Frost Damage and Seed Zone Delineation within an Altitudinal Transect of Pinus devoniana (P. michoacana) in Mexico
Authors: Sáenz-Romero C. , Tapia-Olivares B. L. 
Published: October 2017

Abstract
We explored the patterning of genetic variation among Pinus devoniana Lindl. (also known as P. michoacana Martínez) populations to develop guidelines for seed and seedling movements, intended for improving the matching between genotypes and environments regarding frost tolerance, in reforestation programs. Open-pollinated seed from 16 populations along an altitudinal transect (1600 to 2450 m) were collected near Morelia, State of Michoacán, México. A common-garden provenance test, established with 2.5-year-old seedlings, was assessed for frost resistance conducting a laboratory frost damage test (-9°C). Results indicate that there were significant differences among provenances (P = 0.0261) for frost damage. Variation among provenances was structured as an altitudinal cline, with populations from lower altitudes being the least tolerant to frost. Linear regression statistics suggest that for each increment of 100 m of provenance altitude, there will be a 5.2% decrease in frost damage. We suggest the use of two provisional altitudinal seed zones of 400 m breadth each (lower and upper limits for zone 1: 1600 m and 2000 m of altitude; for zone 2: 2000 and 2400 m, respectively), and for reforestation of a given site, the use of seedlings originated from seed of the same seed zone or within ±200 m of altitude from the elevation of the reforestation site.
Evaluation of Provenances of Eucalyptus camaldulensis and Clones of E. camaldulensis and E. tereticornis at Contrasting Sites in Southern India
Authors: Varghese M. , Harwood C. E. , Hegde R. , Ravi N. 
Published: October 2017

AbstractA total of 188 open-pollinated families of Eucalyptus camaldulensis Dehnh. from 18 Australian natural provenances and 15 selected Indian families of the “Mysore Gum” land race were evaluated in three provenance- family trials at contrasting sites in southern India. At two years of age, the fastest growth was recorded at the driest site in Tamil Nadu, where E. camaldulensis provenances from Queensland were superior to those from Northern Territory and Western Australia, and the Indian land race. Provenance differences were less pronounced at the two higher-rainfall sites in Andhra Pradesh and Kerala. Interaction of provenance performance with site was significant. Within- provenance individual-tree heritabilities for height and diameter at breast height (dbh) were low at the three individual sites, ranging from 0.08 ± 0.05 to 0.19 ± 0.05 for height and 0.10 ± 0.05 to 0.19 ± 0.04 for dbh. Across-site heritabilities, 0.07 ± 0.02 for both height and dbh, were lower than those at individual sites. Phenotypically superior trees were selected from these trials and seven other plantings of E. camaldulensis and Eucalyptus tereticornis Smith in southern India and cloned from basal coppice. A total of 78 E. camaldulensis and 27 E. tereticornis selections, together with thirteen commercially planted Eucalyptus clones and five superior natural provenance seedlots, were tested in clonal trials at three sites in southern India, the different individual treatments being tested at from one to three sites. Three years after planting, most clones selected from E. camaldulensis trials and the commercial Eucalyptus clones were superior in volume production to E. tereticornis clones and seedling controls at a dry site in Tamil Nadu. A smaller number of clones, particularly those of E. camaldulensis, were also superior to seedling controls at an intermediate-rainfall site in Andhra Pradesh. At a third high-rainfall site in Kerala, seedling controls were superior to all but four of 46 clones tested. Significant clone-by-site interaction was observed for growth traits. At the dry site in Tamil Nadu, clones varied widely in their wood basic density from 450 to 700 kg m-3, and there was no significant correlation of clonal values for growth and wood density. The results confirm that clones are best selected and tested in environments similar to those where they will be deployed.
Short Note: The Genetic Correlation Between Air-dried Density and Basic Density in Eucalyptus Nitens Wood Cores
Authors: Hamilton M. G. , Raymond C. A. , Potts B. M. 
Published: October 2017

Abstract
Cores extracted from trees to assess wood chemistry are generally not used to assess basic density in eucalypt pulpwood breeding programmes, as the measurement of basic density requires high temperature drying. However, both wood chemistry and air-dried density can be assessed on the same core. This study found that the inter-trait genetic correlation between core air-dried and basic density to be effectively equal to one in two Tasmanian Eucalyptus nitens progeny trials. This implies that selection for basic density could be undertaken using air-dried density with little or no reduction in genetic gain, thus negating the need to extract a separate core to assess basic density and wood chemistry. The adoption of this practice could considerably reduce the cost of assessing these traits in eucalypt breeding programmes.
Heterogeneity and Spatial Autocorrelation for Chloroplast Haplotypes in Three Old Growth Populations of Northern Red Oak
Authors: Feng Y. , Sun W. , Romero-Severson J. 
Published: October 2017

AbstractIn eastern North America, evidence for cryptic northern refugia could contribute to resolving Reid’s Paradox, the disparity between the rate of oak recolonization indicated by pollen deposition and the rate indicated by contemporary seed dispersal studies. Severe anthropogenic disturbance of oak-dominated forests throughout eastern North America followed by regeneration from isolated patches and deliberate planting in some regions could obscure the signal of discontinuity expected from small, cryptic refugia. In this study of northern red oak, Quercus rubra L., the dominant representative of Quercus section Lobatae in the eastern United States, we address the question of appropriate sample size for accurate detection of the biogeographical distribution of chloroplast haplotype diversity in Q. rubra. We examined chloroplast DNA (cpDNA) variation in all Q. rubra over 17 cm in diameter (310 trees) in three forest fragments with documented histories of minimal disturbance for the last 100-190 years. cpDNA polymorphisms in three intergenic regions revealed different haplotype frequencies between the two local fragments located within 1 km of each other and complete discontinuity for the predominant haplotype between these two sites and a site 207 km distant. Haplotypes displayed positive spatial autocorrelation over 10-40 meter distances. Sample sizes of 10 or fewer taken at 50 meter intervals along a linear transect yielded poor estimates of haplotype frequencies and did not accurately detect haplotype richness.
The Needle Volatile Composition of Pinus nigra J. F. Arnold, P. sylvestris L., P. densiflora Siebold et Zucc. and P. thunbergiana Franco Trispecies Hybrids
Authors: Pfeifhofer H. W. , Idžojtižć M. , Zebec M. 
Published: October 2017

AbstractThe needle volatile composition of two trispecies hard pine hybrids produced by the controlled hybridization and their parents was researched with gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) in order to confirm their hybridity. The analysed trispecies hybrids were: (Pinus nigra x P. sylvestris) x P. densiflora (= nisyde) and (P. nigra x P. sylvestris) x P. thunbergiana (= nisyth). A total of 59 compounds was identified. All identified compounds were terpenes, except one. The trispecies hybrids showed the same qualitative pattern of the needle volatile composition as their parental species. However, there were quantitative differences in several major terpenes. According to the needle volatile composition the hybrids nisyde were more similar to the female parent, whereas the hybrids nisyth were more similar to the male parent. The hybrids nisyth had a considerably higher content of β-pinene (specific component of P. thunbergiana) than the other analyzed groups. The content of thunbergol (specific component of P. densiflora) in the hybrids nisyde was not considerably different in relation to the other groups. The intermediary quality of the hybrids nisyde and nisyth for most components in relation to their parents, as well as the previous morphometric analysis, confirms their hybrid character.
Genetic Variation Within Two Sympatric Spotted Gum Eucalypts Exceeds Between Taxa Variation
Authors: Ochieng J. W. , Shepherd M. , Baverstock P. R. , Nikles G. , Lee D. J. , Henry R. J. 
Published: October 2017

AbstractPopulation substructure and hybridization, among other factors, have the potential to cause erroneous associations in linkage disequilibrium (LD) mapping. Two closely related spotted gum eucalypts, Corymbia variegata and C. henryi (Myrtaceae) occur in sympatry in the east coast of Australia and potentially interbreed. They are morphologically similar but are distinguished as separate species based on capsule and foliage size. To determine whether they hybridize in nature and its implications for LD mapping, we investigated the level of molecular divergence between the two species at two sympatric locations separated by 300 kilometres. Very few individuals of intermediate morphology were identified, despite the two species occurring only metres apart. Analysis of genetic structure using 12 microsatellite loci showed that genetic differentiation between populations of the same species at different locations (FST= 0.07 for both species; p = 0.0001) was significantly higher than that observed between species at each location (mean FST= 0.02 and 0.04 for Cherry tree and Bunyaville respectively; p = 0.0001; all Mann-Whitney U-test p ≤ 0.01). No species-specific alleles or significant allele frequency differences were detected within a site, suggesting recurr#ent local gene flow between the two species. The lack of significant allele frequency differences implies no population stratification along taxonomic lines. This suggested that there is little concern for cryptic hybridization when sampling from sites of sympatry for LD mapping.