Download or read book Switchgrass Panicum Virgatum L Intraspecific Variation and Temperature Tolerance Classification Using in Vitro Seed Germination Assay written by Ramdeo Seepaul and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An experiment was conducted to determine temperature effects on switchgrass seed germination, a native species with feedstock potential for the biofuel industry. Stratified seeds were germinated at constant temperatures, 15 to 45°C with 5°C interval. Maximum seed germination (MSG) and germination rate (GR), estimated by fitting sigmoid function to germination-time series data, varied among genotypes. Quadratic and bilinear models best described the MSG and GR responses to temperature, respectively. The mean cardinal temperatures, minimum, optimum and maximum, were 8.1, 26.6 and 45.1°C for MSG and 11.1, 33.1 and 46.0°C for GR, respectively, varied among genotypes. Genotypes were classified for temperature tolerance based on cumulative temperature response index: 'Summer' and 'Expresso' were identified as the most heat- and cold-tolerant genotypes, respectively. The functional algorithms and identified tolerant genotypes may be used to improve switchgrass models for field applications and breeding programs to develop new genotypes with enhanced tolerance for niche environments.
Download or read book Switchgrass Panicum Virgatum L Intraspecific Variation and Thermotolerance Classification Using in Vitro Seed Germination Assay written by and published by . This book was released on 2011 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cardinal temperatures for plant processes have been used for thermotolerance screening of genotypes, geoclimatic adaptability determination and phenological prediction. Current simulation models for switchgrass (Panicum virgatum L.) utilize single cardinal temperatures across genotypes for both vegetative and reproductive processes although in-tra-specific variation exists among genotypes. An experiment was conducted to estimate the cardinal temperatures for seed germination of 14 diverse switchgrass genotypes and to classify genotypes for temperature tolerance. Stratified seeds of each genotype were germinated at eight constant temperatures from 10 °C to 45 °C under a constant light intensity of 35 [mu]mol m-2s-1 for 12 hd-1. Germination was recorded at 6-h intervals in all treatments. Maximum seed germination (MSG) and germination rate (GR), estimated by fitting Sigmoidal function to germination-time series data, varied among genotypes. Quadratic and bilinear models best described the MSG and GR responses to temperature, respectively. The mean cardinal temperatures, Tmin, Topt, and Tmax, were 8.1, 26.6, and 45.1 °C for MSG and 11.1, 33.1, and 46.0 °C for GR, respectively. Cardinal temperatures for MSG and GR; however, varied significantly among genotypes. Genotypes were classified as sensitive (Cave-in-Rock, Dacotah, Expresso, Forestburg, Kanlow, Sunburst, Trailblazer, and Tusca), intermediate (Alamo, Blackwell, Carthage, Shawnee, and Shelter) and tolerant (Summer) to high temperature based on cumulative temperature response index (CTRI) estimated by summing individual response indices estimated from the MSG and GR cardinal temperatures. Similarly, genotypes were also classified as sensitive (Alamo, Blackwell, Carthage, Dacotah, Shawnee, Shelter and Summer), moderately sensitive (Cave-in-rock, Forestburg, Kanlow, Sunburst, and Tusca), moderately tolerant (Trailblazer), and tolerant (Expresso) to low temperatures. The cardinal temperature estimates would be useful to improve switchgrass models for field applications. Additionally, the identified cold- and heat-tolerant genotypes can be selected for niche environments and in switchgrass breeding programs to develop new genotypes for low and high temperature environments.
Download or read book Switchgrass written by Andrea Monti and published by Springer Science & Business Media. This book was released on 2012-03-14 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for renewable energies from biomass is growing steadily as policies are enacted to encourage such development and as industry increasingly sees an opportunity to develop bio-energy enterprises. Recent policy changes in the EU, USA and other countries are spurring interest in the cultivation of energy crops such as switchgrass. Switchgrass has gained and early lead in the race to find a biomass feedstock for energy production (and for the almost requisite need for bio-based products from such feedstocks). Switchgrass: A Valuable Biomass Crop for Energy provides a comprehensive guide to the biology, physiology, breeding, culture and conversion of switchgrass as well as highlighting various environmental, economic and social benefits. Considering this potential energy source, Switchgrass: A Valuable Biomass Crop for Energy brings together chapters from a range of experts in the field, including a foreword from Kenneth P. Vogel, to collect and present the environmental benefits and characteristics of this a crop with the potential to mitigate the risks of global warming by replacing fossil fuels. Including clear figures and tables to support discussions, Switchgrass: A Valuable Biomass Crop for Energy provides a solid reference for anyone with interest or investment in the development of bioenergy; researchers, policy makers and stakeholders will find this a key resource.
Download or read book Switchgrass Panicum Virgatum written by Clinton H. Wasser and published by . This book was released on 1986 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A plant materials report on witchgrass (Panicum virgatum) is provided as Section 7.1.2 of the US Army Corps of Engineers Wildlilfe Resources Management Manual. The report was prepared as guide to assist the Corps District or project biologist with the selection, cultivation, and management of suitable plant materials for wildlife and habitat development programs. Topics covered include description, distribution, habitat requirements, wildlife value, establishment, maintenance, and cautions and limitations. Switchgrass is a native, perennial, warm-season bunchgrass and is a major component of the Midwestern tallgrass prairie. The seeds, foliage, and stiff upright stems provide food and cover for a variety of wildlife species. Distinguishing characteristics of switchgrass are describedl and the species distribution and region of maximum abundance are given. Soil, moisture, and shade requirements are specified, and common plant associates in tallgrass prairies are listed. Food and cover value for several species of wildlife is discussed. The section on establishment provides guidelines for site selection, site preparation, propagule selection, and planting methods. Recommended planting mixtures are given for several regions. Maintenance requirements and cautions and limitations are discussed.
Download or read book Germination Studies with Plant Selections of Switchgrass Panicum Virgatum L written by Ming-Yu Li and published by . This book was released on 1951 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dacotah Switchgrass written by and published by . This book was released on 1990 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Responses of Switchgrass Panicum Virgatum L to Precipitation Amount and Temperature written by Jeffrey C. Hartman and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Anthropogenic climate change is likely to alter the function and composition of ecosystems worldwide through increased precipitation variability and temperatures. To predict ecosystem responses, a greater understanding of the physiological and growth responses of plants is required. Dominant species drive ecosystem responses, and it is essential to understand how they respond to understand potential ecosystem changes. Dominant species, such as switchgrass (Panicum virgatum L.), posses large genotypic and phenotypic variability, which will impact the degree of responses to projected climate changes. I studied the physiological and growth responses of switchgrass, a common perennial warm-season C4 grass that is native to the tallgrass prairie, to alterations in precipitation amount and temperature. The first experiment I conducted focused on the responses of three ecotypes of P. virgatum to three precipitation regimes (average, 25% below, 25% above). I concluded that the physiological responses of photosynthesis, stomatal conductance, transpiration, dark-adapted fluorescence, and mid-day water potential in P. virgatum were explained by ecotypic differences. Robust responses to altered precipitation were seen in the water use efficiency, mid-day water potential, and aboveground biomass. Ecotypic differences were also seen in several aboveground biomass variables, and most strikingly in flowering times and rates. There were few interactions between ecotype and precipitation, suggesting precipitation is a strong driver of biomass production, whereas adaption of ecotypes to their local environment affects physiological processes. A second experiment studied the response of local populations of P. virgatum to nocturnal warming. Results showed significant differences in daytime E, daytime gs, and flowering phenology between treatments. Differences in aboveground biomass were between topographic positions. I concluded that water availability, based on topographic position, is a strong driver of P. virgatum aboveground biomass production, but nocturnal warming has the potential to impact flowering phenology, physiological responses, and exacerbate plant water stress. I also reviewed the literature on the ecological effects of implementing switchgrass cultivation for biofuel. From the literature review, I concluded that large-scale switchgrass cultivation will have widespread ecological impacts. If landscape heterogeneity is maintained through harvest rotations, no till farming, and mixed species composition, ecosystem services can be maintained while providing economic value.
Download or read book Switchgrass written by Andrea Monti and published by Springer Science & Business Media. This book was released on 2012-03-09 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for renewable energies from biomass is growing steadily as policies are enacted to encourage such development and as industry increasingly sees an opportunity to develop bio-energy enterprises. Recent policy changes in the EU, USA and other countries are spurring interest in the cultivation of energy crops such as switchgrass. Switchgrass has gained and early lead in the race to find a biomass feedstock for energy production (and for the almost requisite need for bio-based products from such feedstocks). Switchgrass: A Valuable Biomass Crop for Energy provides a comprehensive guide to the biology, physiology, breeding, culture and conversion of switchgrass as well as highlighting various environmental, economic and social benefits. Considering this potential energy source, Switchgrass: A Valuable Biomass Crop for Energy brings together chapters from a range of experts in the field, including a foreword from Kenneth P. Vogel, to collect and present the environmental benefits and characteristics of this a crop with the potential to mitigate the risks of global warming by replacing fossil fuels. Including clear figures and tables to support discussions, Switchgrass: A Valuable Biomass Crop for Energy provides a solid reference for anyone with interest or investment in the development of bioenergy; researchers, policy makers and stakeholders will find this a key resource.
Download or read book Forestburg Switchgrass written by and published by . This book was released on 1988 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transcriptome Changes in Switchgrass Panicum Virgatum L Seeds when Hydrogen Peroxide is Applied to Alleviate Dormancy written by Martha Isabel Montanez Diaz and published by . This book was released on 2011 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Evaluation of Plant Variation in Selected Populations of Switchgrass Panicum Virgatum L written by Steve A. Eberhart and published by . This book was released on 1958 with total page 174 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Compendium of Bioenergy Plants written by Hong Luo and published by CRC Press. This book was released on 2014-03-14 with total page 463 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the most comprehensive reviews on the latest development of switchgrass research including the agronomy of the plant, the use of endophytes and mycorrhizae for biomass production, genetics and breeding of bioenergy related traits, molecular genetics and molecular breeding, genomics, transgenics, processing, bioconversion, biosyst
Download or read book Switchgrass Panicum Virgatum L Distribution Genetic Diversity and Pollen mediated Gene Flow written by and published by . This book was released on 2014 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reproduction and Bioconfinement of MiR156 Transgenic Switchgrass Panicum Virgatum L written by Chelsea Renai Johnson and published by . This book was released on 2017 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Genetic engineering of switchgrass (Panicum virgatum L.), an emerging cellulosic bioenergy feedstock, has been performed to alter cell walls for improved biofuel conversion. However, gene flow from transgenic switchgrass presents regulatory issues that may prevent commercialization of the genetically engineered crop in the eastern United States. Depending on its expression level, microRNA156 (miR156) can reduce, delay or eliminate flowering, which may be useful to mitigate transgene flow. However, flowering transition is dependent upon both environmental and genetic cues. In this study of transgenic switchgrass, two low (T14 and T35) and two medium (T27 and T37) miR156 overexpressing 'Alamo' lines and nontransgenic control plants were used. A two-year field experiment was performed to compare flowering, reproduction, and biomass yield in eastern Tennessee, U.S.A. Growth chamber studies assessed temperature and photoperiod effects on flowering and reproduction across a simulated latitudinal cline. In the field, medium miR156 overexpression line T37 resulted in the best overall combination of bioconfinement and biomass production. Though line T37 did flower, not all plants produced panicles, and panicle production was delayed in both years. Line T37 also produced fewer panicles, with a 65.9% reduction in year one and 23.8% reduction in year two over controls. T37 panicles produced 70.6% less flowers than control panicles during the second field year with commensurate decreased seed yield: 1205 seeds per plant vs. 18,539 produced by each control. These results are notable given that line T37 produced equivalent vegetative aboveground biomass as controls. In latitudinal simulation growth chambers, elevated temperatures and decreased daylength promoted flowering of the miR156 transgenic switchgrass lines. As temperatures increased and day lengths decreased, more plants in lines T35, T37, and controls produced panicles. The simulated (Ecuador) tropical conditions were the only chambers in which three of the four transgenic lines flowered. These results suggest that miR156 overexpression levels found in transgenic line T37 can be useful for bioconfinement, and the plants can significantly reproduce in tropical conditions, which would enable plant breeding for line improvement. Furthermore, the study suggests additional ways that miR156 can be manipulated to improve both biomass production and bioconfinement.
Download or read book Screening Switchgrass Panicum Virgatum L for Water Stress Tolerance written by Mohamed Ali Saed Fahej and published by . This book was released on 2012 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dormancy Mechanisms of Switchgrass Panicum Virgatum L Seeds written by Brietta D. Murphy and published by . This book was released on 2008 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of Swicthgrass Panicum Virgatum L as a Bioenergy Feedstock for the Northeastern and Mid Atlantic USA written by Laura Mary Cortese and published by . This book was released on 2014 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Switchgrass (Panicum virgatum L.) is a warm season, C4 perennial grass native to most of North America with numerous applications, including use as a bioenergy feedstock. Although switchgrass has emerged as a bioenergy crop throughout the midwestern and southern US, little information is available on the performance of switchgrass in the Northeast/Mid-Atlantic. In the first genetic diversity study of switchgrass populations to utilize both morphological and molecular markers, it was found that the combination of morphological and molecular markers differentiated populations best, and should be useful in future applications such as genetic diversity studies, plant variety protection, and cultivar identification. In a study that evaluated several bioenergy traits of 10 switchgrass cultivars in NJ, populations with improved agronomic characteristics were identified. Cultivar Timber exhibited the best combination of characteristics and has promise for biomass production in the Northeast/Mid-Atlantic US. In a third study, the effects of cultivar, location, and harvest date on biomass yield, dry matter, ash, and combustion energy content in three switchgrass cultivars were investigated. Results indicated that a January harvest allowed for optimal feedstock quality and that cultivars Alamo, Carthage, and Timber produced high yielding, high quality biomass. In an effort to improve the establishment capacity of switchgrass, a fourth study was conducted examining the effects of divergent selection for seed weight on germination and emergence in three switchgrass populations over two cycles of selection, and cold stratification on germination in the derived populations. Selection for seed weight alone was not sufficient to improve germination and germination rate in populations tested, while cold stratification improved germination. Therefore, breeding efforts should be directed towards reducing dormancy in order to improve switchgrass germination and establishment. The final two studies examined genotype x environment effects, estimated broad-sense heritability, and stability analysis on lignocellulosic and agronomic traits in switchgrass clones grown on marginal and prime soils in NJ. Results support the existence of both specifically and broadly adapted switchgrass germplasm, and demonstrate the need for evaluation of germplasm across multiple years and environments (including prime and marginal sites) in order to develop cultivars with optimal lignocellulosic and agronomic characteristics.
