A5052426730- Nuclear reactor physics and engineering
- Plant Reproductive Biology
- Forest ecology and management
- Nuclear and radioactivity studies
- Plant Physiology and Cultivation Studies
- Plant tissue culture and regeneration
- Nuclear Materials and Properties
- Seedling growth and survival studies
- Plant Molecular Biology Research
- Plant Water Relations and Carbon Dynamics
- Graphite, nuclear technology, radiation studies
- Forest Insect Ecology and Management
- Plant Pathogens and Fungal Diseases
- Tree Root and Stability Studies
- Nuclear Engineering Thermal-Hydraulics
- Plant and animal studies
- Plant responses to elevated CO2
- Advanced Data Processing Techniques
- Ecology and Vegetation Dynamics Studies
- Seed Germination and Physiology
- Metallurgical Processes and Thermodynamics
- Simulation Techniques and Applications
- Modeling and Simulation Systems
- Forest Management and Policy
- Fusion materials and technologies
Oak Ridge National Laboratory
2015-2024
University of Maine
2005-2022
National Technical Information Service
2021
University of Wisconsin–Madison
1992-2017
Idaho National Laboratory
2016
Northern Arizona University
2008
Eastern Maine Healthcare Systems
2008
Weyerhaeuser (United States)
1974-1981
Middlebury College
1970-1975
Yale University
1968-1973
Maturation in conifers includes several distinct and persistent changes the growth habits of apical meristems. Despite many studies on maturation conifers, there are still aspects process that have not been elucidated. For example, it is known why cotyledon-derived tissue culture plantlets rapid, whereas natural gradual. Also, whether rejuvenation occurs as a result mature cells reverting to juvenile state, or results from selective multiplication never matured. In this paper, I review...
The contribution of changes in meristem behavior to age-related decline forest productivity is poorly understood. We studied trends needle morphology and gas exchange a population red spruce (Picea rubens Sarg.) growing multi-cohort stand where trees ranged from first-year germinants over 150 years old, as well grafted scions these trees. In the field study, foliar were determined six cohorts ranging age 2 120 years, differences characteristics compared between 60- 120-year classes....
Woody plants exhibit significant and predictable patterns of change in morphology physiology as they become older larger. Four models potential pathways controlling these changes are presented: a stimulus-response model which fully developed organs respond to environment (defined here everything external the organ); an extrinsic attributes developing determined by environmental factors; intrinsic result programmed gene expression; extrinsic-intrinsic expression induced factors. We review...
The effect of maturation on the morphological and photosynthetic characteristics, as well expression two genes involved in photosynthesis developing, current year foliage Eastern larch (Larix laricina [Du Roi]) is described. These effects were observed during third growing season after grafting scions from trees different ages onto 2 old rootstock. Specific leaf weight (gram dry per square meter), cross-sectional area (per millimeter), chlorophyll content (milligram gram weight) all increase...
Differential display reverse transcription-polymerase chain reaction was used to detect the induction of gene expression during adventitious root formation in loblolly pine (Pinus taeda) after treatment with exogenous auxin indole-3-butyric acid. A BLAST search GenBank database using one clones obtained revealed very strong similarity alpha-expansin family angiosperms. near-full-length sequence 5'- and 3'-rapid amplification cDNA end cloning, deduced amino acid highly conserved relative...
A comparison of rooting ability stem cuttings made from hypocotyls and epicotyls 50‐day‐old seedlings loblolly pine ( Pinus taeda L. ) reveals a dramatic decline by epicotyl cuttings, which do not root at all in 20–30 days the presence or absence auxin. In contrast, almost during this time, but only exogenously applied The failure to does appear be due differences [ 14 C]‐labeled auxin uptake, transport, metabolism, tissue distribution two types cuttings. At cellular level, initial responses...
The time course of maturation in eastern larch (Larix laricina [Du Roi] K. Koch) was examined by grafting scions from trees different ages onto 2-year-old root stock and following scion development for several years. Height, diameter, foliar chlorophyll content, rooting ability scion-derived cuttings all varied linearly as a function log(10) age. Chlorophyll content (milligrams per gram dry weight) increased while height, to decreased with age (P < 0.01). tendency toward orthotropic growth...
The characteristic decline in height growth that occurs over a tree's lifespan is often called "age-related decline." But the reduction aging trees function of age or size? We grafted shoot tips across different ages and sizes Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) to determine whether mediated by tree size apical meristem. also evaluated reduced carbon assimilation plays an important role decline. In one experiment we cut from old-growth, young-mature seedling them onto...
The growth behavior of grafted scions from 1‐, 4‐, 8‐ and 12‐year‐old ortets representing five half‐sib loblolly pine families was observed over a two‐year period (three for strobilus production) following grafting. Significant, persistent decreases in total number cycles produced, height diameter increment, branches foliar surface area scion biomass were with increasing age. Needle length, diameter, ability to form male female strobili increased persistence these differences is not function...
Phenotypic plasticity in needle morphology with increasing tree size and age was investigated by comparing four classes of red spruce (Picea rubens Sarg.) ranging from juvenile (3–12 years old) to mature (over 100 old). With increase there were significant increases leaf mass per unit area (LMA), mesophyll vascular bundle as a percentage total cross-sectional area, stomatal density. Within the bundle, both xylem tracheid lumen increased significantly, whereas air space decreased. These...
Hypocotyl cuttings (from 20- and 50-day-old Pinus taeda L. seedlings) rooted readily within 30 days in response to exogenous auxin, while epicotyl rarely formed roots 60 days. Responses auxin during adventitious rooting included the induction of cell reorganization division, followed by organization root meristem. Explants from bases both hypocotyl callus tissue a variety auxins, but did not organize meristems. Auxin-induced division was observed cambial region 4 days, later spread outer...
After about 20 days, hypocotyl cuttings from 20-day-old loblolly pine (Pinus taeda L.) seedlings rooted easily in the presence of auxin indole-3-butyric acid (IBA), with roots forming directly xylem parenchyma. In contrast, woody 1-2-year-old hedged formed indirectly callus tissue 60-90 but IBA had little effect on rooting. Variation rooting among hypocotyls both half- and full-sib families was highly significant response to IBA, did not occur within days unless applied. Hypocotyls poor...