248 research outputs found

    Cryopreservation of Dormant Buds from Diverse Fraxinus Species

    Get PDF
    Ash (Fraxinus) is an economically important tree genus in the landscape industry, as well as a key component of North American forests, especially in the North Central United States and adjacent regions in Canada. In recent years, the Emerald Ash Borer beetle (Agrilus planipennis) has significantly threatened the survival of native North American Fraxinus species. A dormant-bud cryopreservation technique has been developed as a method to conserve specific clones of ash. Dormant buds of three ash species were successfully cryopreserved when desiccated on their stem sections to 30% moisture content (w/v) and then cooled at rates of either −1°C/h or −5°C/day to either −30 or −35°C before immersion in liquid nitrogen vapor (LNV). Stem sections were removed from LNV, warmed, and rehydrated, and their buds grafted onto rootstocks to evaluate survival. Recovery percentages ranged from 34 to 100% after LNV exposure and were dependent upon accession and cooling rate. The cryopreservation methods proposed herein can complement seed-collection efforts aimed at conserving diversity, supplementing ex situ genebank and botanic-garden collections

    Cryopreservation of Populus Trichocarpa and Salix Dormant Buds with Recovery by Grafting or Direct Rooting

    Get PDF
    BACKGROUND: Methods are needed for the conservation of clonally maintained trees of Populus and Salix. In this work, Populus trichocarpa and Salix genetic resources were cryopreserved using dormant scions as the source explant. OBJECTIVE: We quantified the recovery of cryopreserved materials that originated from diverse field environments by using either direct sprouting or grafting. MATERIALS AND METHODS: Scions (either at their original moisture content of 48 to 60% or dried to 30%) were slowly cooled to -35°C, transferred to the vapor phase of liquid nitrogen (LNV, -160°C), and warmed before determining survival. RESULTS: Dormant buds from P. trichocarpa clones from Westport and Boardman, OR had regrowth levels between 42 and 100%. Direct rooting of cryopreserved P. trichocarpa was also possible. Ten of 11 cryopreserved Salix accessions, representing 10 different species, exhibited at least 40% bud growth and rooting after 6 weeks when a bottom-heated rooting system was implemented. CONCLUSION: We demonstrate that dormant buds of P. trichocarpa and Salixaccessions can be cryopreserved and successfully regenerated without the use of tissue culture

    Advances in shrub-willow crops for bioenergy, renewable products, and environmental benefits

    Get PDF
    Short-rotation coppice systems like shrub willow are projected to be an important source of biomass in the United States for the production of bioenergy, biofuels, and renewable bio-based products, with the potential for auxiliary environmental benefits and multifunctional systems. Almost three decades of research has focused on the development of shrub willow crops for biomass and ecosystem services. The current expansion of willow in New York State (about 500 ha) for the production of renewable power and heat has been possible because of incentive programs offered by the federal government, commitments by end users, the development of reliable harvesting systems, and extension services offered to growers. Improvements in the economics of the system are expected as willow production expands further, which should help lower establishment costs, enhance crop management options and increase efficiencies in harvesting and logistics. Deploying willow in multifunctional value-added systems provides opportunities for both potential producers and end users to learn about the system and the quality of the biomass feedstock, which in turn will help overcome barriers to expansion

    Evaluation of a Single-Pass, Cut and Chip Harvest System on Commercial-Scale, Short-Rotation Shrub Willow Biomass Crops

    Get PDF
    Harvesting is the single largest cost in the production of short rotation woody crops (SRWC) like shrub 8 willow and previous systems tested in North America have not been effective for the size of material grown. The 9 objective of this study was to evaluate the performance of a single-pass, cut and chip harvester in conjunction with 10 two locally-sourced chip collection systems on 54 ha of coppiced willow harvests in New York State. Harvesting 11 and collection equipment was tracked for 153 loads over 10 days of harvesting using GPS dataloggers. Effective 12 material capacities (Cm) increased linearly with standing biomass up to 40 to 45 Mgwet ha-1 because ground speed 13 was limited by ground conditions. This relationship changed dramatically with standing biomass in the 40 – 90 14 Mgwet ha-1 range, where Cm plateaued between 70 and 90 Mgwet hr-1 and was limited by crop conditions and 15 harvester capacity. The relationship between standing biomass and the harvester’s Cm will probably change under 16 different crop and ground conditions. The size of the harvester and the experience of the operator are other factors. 17 This nonlinear relationship will impact cost and optimization modeling SRWC systems. Improperly sized headland 18 and long haul distances impeded the performance of locally sourced collection systems resulting in a 33% decrease 19 in Cm from the field to the headlands, and 66% from the field to short-term storage as biomass moves through the 20 system

    ADVANCED CUTTINGS TRANSPORT STUDY

    Get PDF
    This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members

    Facial nerve electrodiagnostics for patients with facial palsy : a clinical practice guideline

    Get PDF
    Purpose Facial nerve electrodiagnostics is a well-established and important tool for decision making in patients with facial nerve diseases. Nevertheless, many otorhinolaryngologist-head and neck surgeons do not routinely use facial nerve electrodiagnostics. This may be due to a current lack of agreement on methodology, interpretation, validity, and clinical application. Electrophysiological analyses of the facial nerve and the mimic muscles can assist in diagnosis, assess the lesion severity, and aid in decision making. With acute facial palsy, it is a valuable tool for predicting recovery. Methods This paper presents a guideline prepared by members of the International Head and Neck Scientific Group and of the Multidisciplinary Salivary Gland Society for use in cases of peripheral facial nerve disorders based on a systematic literature search. Results Required equipment, practical implementation, and interpretation of the results of facial nerve electrodiagnostics are presented. Conclusion The aim of this guideline is to inform all involved parties (i.e. otorhinolaryngologist-head and neck surgeons and other medical specialists, therapeutic professionals and the affected persons) and to provide practical recommendations for the diagnostic use of facial nerve electrodiagnostics.Peer reviewe
    corecore