Cooperative Second-Generation Breeding and Testing of Coastal Douglas-fir in the US Pacific Northwest

Forest tree improvement got underway in the Pacific Northwest of the USA in the 1950s. Graft incompatibility became evident by the early 1960s and dampened enthusiasm for grafted clonal orchards for this species A different approach, the IFA-PNW �Progressive Tree Improvement System� was launched in 1966. The emphasis here was on forming local cooperatives to share costs, and on progeny testing large numbers of trees using wind-pollinated seed in small testing zones. This phase ran from 1967 till 1993, during which over 26,000 first-generation parents were tested in 109 breeding units (between local cooperatives, the USDI Bureau of Land Management, the USDA Forest Service and WA Department of Natural Resources), with over 3 million progeny test trees planted. A second-generation breeding and testing strategy was developed between 1996 and 1997: Adjacent first-generation testing programs could merge to share genetic material for breeding and testing. Breeding population size for any merged programs should be at least 300 selections. Within a breeding population, breeding groups of 20-30 selections each would be used to manage inbreeding and create multiple populations. The top 10-20 percent of selections within a breeding population could also be assigned an elite population. A minimum of nine breeding groups would be needed within a given testing zone. Each new testing zone was to use all of the families from "local" breeding groups and only the most elite selections from breeding groups originating further away from the testing zone. Each selection would be used in at least two crosses. The committee proposed using three types of tests, each with a specific purpose and design: family-ranking/selection tests; longterm stability tests; and adaptability-screening tests. Breeding and testing is in various stages of completion for seven different programs, which would lead to nine or 10 testing zones. The rule of thumb in choosing selections (first-generation parents, forward selections from open-pollinated progeny tests and from full-sib orchards) crossed to form the second-generation populations has been a 1 in 10 between-family selection intensity. Most selections were based on age-15 height. Where available information on stem sinuosity, forking, ramicorn branches and wood specific gravity were also considered. Between five and six tests have been established per testing zone, with 20 trees planted per family per site in single-tree plots. Trials established to date have contained from 143 to 283 full-sib crosses. All tests are fenced to protect the seedlings from browse. Tests will probably be measured twice, around seven and 12 years from seed (or when the trees are 15 and 30 feet tall respectively).Papers and abstracts from the 27th Southern Forest Tree Improvement Conference held at Oklahoma State University in Stillwater, Oklahoma on June 24-27, 2003

Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs

Measurements on growth traits up to 41 years of age from 68 progeny sites in eight first-generation breeding zones of coastal Douglas-fir (Pseudotsuga menziesii [MIRB.] FRANCO var. menziesii) in the US Pacific Northwest were used to investigate age trends of genetic parameters and to determine optimum age of selection. Heritabilities and age-age genetic correlations were estimated using univariate or bivariate mixed model analyses. Heritability estimates tended to increase with age for both total growth and growth increment traits. The estimates showed different age trends among breeding zones, but the differences were generally small. Age-age genetic correlations for total growth traits fitted Lambeth’s model surprisingly well, despite the data being collected from multiple breeding zones. Using rotation-age (i.e., 50yr) volume as the selection criterion, the greatest correlated gains per year were achieved by making family selection at juvenile ages (i.e., 9 for height, 13 for diameter, and 11 for volume). Similar results were obtained for within-family selection except that the optimum ages of selection were 2~4 years later than that from family selection, i.e., 11 for height, 15 for diameter and volume. Early selection on total height was always more efficient and had earlier optimum ages than on other growth traits. The optimum ages of early family selection on total growth were 4~11 years earlier than on the corresponding growth increment traits. It was also evident that the optimum ages of selection occurred later for slow-growth trials than for fast-growing trials.This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18.Keywords: Age-age genetic correlation, Heritability, Selection efficiency, Growth, Early selection, Douglas-fir, Growth increment, Optimum ag

GPs' decision-making when prescribing medicines for breastfeeding women: Content analysis of a survey

<p>Abstract</p> <p>Background</p> <p>Many breastfeeding women seek medical care from general practitioners (GPs) for various health problems and GPs may consider prescribing medicines in these consultations. Prescribing medicines to a breastfeeding mother may lead to untimely cessation of breastfeeding or a breastfeeding mother may be denied medicines due to the possible risk to her infant, both of which may lead to unwanted consequences. Information on factors governing GPs' decision-making and their views in such situations is limited.</p> <p>Methods</p> <p>GPs providing shared maternity care at the Royal Women's Hospital, Melbourne were surveyed using an anonymous postal survey to determine their knowledge, attitudes and practices on medicines and breastfeeding, in 2007/2008 (n = 640). Content analysis of their response to a question concerning decision-making about the use of medicine for a breastfeeding woman was conducted. A thematic network was constructed with basic, organising and global themes.</p> <p>Results</p> <p>335 (52%) GPs responded to the survey, and 253 (76%) provided information on the last time they had to decide about the use of medicine for a breastfeeding woman. Conditions reported were mastitis (24%), other infections (24%) and depressive disorders (21%). The global theme that emerged was "<it>complexity of managing risk in prescribing for breastfeeding women"</it>. The organising themes were: <it>certainty around decision-making; uncertainty around decision-making; need for drug information to be available, consistent and reliable; joint decision-making; the vulnerable "third party" </it>and <it>infant feeding decision</it>. Decision-making is a spectrum from a straight forward decision, such as treatment of mastitis, to a complicated one requiring multiple inputs and consideration. GPs use more information seeking and collaboration in decision-making when they perceive the problem to be more complex, for example, in postnatal depression.</p> <p>Conclusion</p> <p>GPs feel that prescribing medicines for breastfeeding women is a contentious issue. They manage the risk of prescribing by gathering information and assessing the possible effects on the breastfed infant. Without evidence-based information, they sometimes recommend cessation of breastfeeding unnecessarily.</p

NMR methods to monitor the enzymatic depolymerization of heparin

Heparin and the related glycosaminoglycan, heparan sulfate, are polydisperse linear polysaccharides that mediate numerous biological processes due to their interaction with proteins. Because of the structural complexity and heterogeneity of heparin and heparan sulfate, digestion to produce smaller oligosaccharides is commonly performed prior to separation and analysis. Current techniques used to monitor the extent of heparin depolymerization include UV absorption to follow product formation and size exclusion or strong anion exchange chromatography to monitor the size distribution of the components in the digest solution. In this study, we used 1H nuclear magnetic resonance (NMR) survey spectra and NMR diffusion experiments in conjunction with UV absorption measurements to monitor heparin depolymerization using the enzyme heparinase I. Diffusion NMR does not require the physical separation of the components in the reaction mixture and instead can be used to monitor the reaction solution directly in the NMR tube. Using diffusion NMR, the enzymatic reaction can be stopped at the desired time point, maximizing the abundance of larger oligosaccharides for protein-binding studies or completion of the reaction if the goal of the study is exhaustive digestion for characterization of the disaccharide composition. In this study, porcine intestinal mucosa heparin was depolymerized using the enzyme heparinase I. The unsaturated bond formed by enzymatic cleavage serves as a UV chromophore that can be used to monitor the progress of the depolymerization and for the detection and quantification of oligosaccharides in subsequent separations. The double bond also introduces a unique multiplet with peaks at 5.973, 5.981, 5.990, and 5.998 ppm in the 1H-NMR spectrum downfield of the anomeric region. This multiplet is produced by the proton of the C-4 double bond of the non-reducing end uronic acid at the cleavage site. Changes in this resonance were used to monitor the progression of the enzymatic digestion and compared to the profile obtained from UV absorbance measurements. In addition, in situ NMR diffusion measurements were explored for their ability to profile the different-sized components generated over the course of the digestion

Analysis and characterization of heparin impurities

This review discusses recent developments in analytical methods available for the sensitive separation, detection and structural characterization of heparin contaminants. The adulteration of raw heparin with oversulfated chondroitin sulfate (OSCS) in 2007–2008 spawned a global crisis resulting in extensive revisions to the pharmacopeia monographs on heparin and prompting the FDA to recommend the development of additional physicochemical methods for the analysis of heparin purity. The analytical chemistry community quickly responded to this challenge, developing a wide variety of innovative approaches, several of which are reported in this special issue. This review provides an overview of methods of heparin isolation and digestion, discusses known heparin contaminants, including OSCS, and summarizes recent publications on heparin impurity analysis using sensors, near-IR, Raman, and NMR spectroscopy, as well as electrophoretic and chromatographic separations

Rootstock effects on scion growth and reproduction in 8-year-old grafted loblolly pine

Contributions of sites, rootstocks, and scion clones (and the nteractions between these factors) to scion growth and reproduction were studied in loblolly pine (Pinus taeda L.). Twenty-five full-sib families were used as rootstocks. Six scion clones were grafted on them in all combinations. Study sites were three seed orchards in the southeastern United States; trees were measured 8 years after grafting. Scion elongation, diameter at breast height (DBH) of the main leader, crown diameter, cone counts, and number of male and female strobili were measured at all sites. Crown diameter and tree height were combined into a crown volume index. Highly significant differences existed among scion clones for all traits. When analyzed over all three sites, the only trait with significant rootstock effects was DBH. There were significant rootstock × scion interactions for total scion elongation, crown volume index, and DBH and significant site × scion interactions for strobili counts and cone count. In analyses by clone, rootstock effects were expressed differently in the different clones. There were significant rootstock effects for three traits in each of three clones and no effects at all in two clones. For all traits the largest variance component was for either site or scion clone. Components for rootstocks were small or zero. These results show that the scion clone and site have more control on scion growth and reproduction of grafted loblolly pine than the rootstock. The study did not identify full-sib families that (as rootstocks) would significantly reduce scion elongation or significantly increase cone production, for all six scion clones at all three sites

Date of earlywood-latewood transition in provenances and families of loblolly pine, and its relationship to growth phenology and juvenile wood specific gravity

When grown together in plantations, fast-growing southern and coastal sources of loblolly pine (Pinus taeda L.)often have lower wood specific gravity than northern and inland sources. This study investigated whether this phenomenon could be explained by a later transition to latewood, associated with a longer period of height growth, of the fast-growing sources. Seven to nine open-pollinated families, from each of four provenances, were grown at two locations in southwest Georgia. Tree cambia were wounded with a needle during summer and fall of the fifth and sixth growing seasons (1993 and 1994). The wounding was done to leave a mark in the xylem used later to determine whether earlywood or latewood was being produced at the time of wounding. Provenances were significantly different for the date of transition in 1994, with 22 days between the earliest and the latest. For most families, latewood transition followed height growth cessation in 1993, but preceded it in 1994. The date of latewood transition had a strong positive correlation (family mean basis across provenances) with the date of height growth cessation and a moderate negative correlation with specific gravity. Juvenile wood specific gravity had a weak (nonsignificant) negative correlation with annual height increment and a stronger negative correlation, significant in 1993, with diameter increment. Correlations within provenances were weak or close to zero. This study provided evidence for an association (especially at the provenance level) between a later cessation of height growth, a later transition to latewood, and lower specific gravity in 5- and 6-year-old trees