Download or read book Effects of Elevated CO2 on Creeping Bentgrass Agrostis Stolonifera L During the Ante Meridiem Photoperiod for Summer Heat Stress Tolerance written by and published by . This book was released on 2008 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for optimum putting conditions requires golf course superintendents to manage cool season creeping bentgrass (Agrostis stolonifera L.) in the transition zone and upper south. Summer heat stress combined with low mowing heights and constant traffic are challenges that superintendents must face in order to successfully manage creeping bentgrass from early May to late September. A field experiment was conducted on a Crenshaw putting green under golf course conditions during the 2006 summer and twice during the 2007 summer in Knoxville, TN. 2006 enriched air treatments of ~692 ppm CO2 and ~891 ppm CO2 were compared to a control of ambient air (~363 ppm CO2). 2007 enriched air treatments of ~716 ppm CO2 and ~1076 ppm CO2 were compared to a control of ambient air (~451 ppm CO2). Indirect heat stress was characterized by measuring the accumulation of total nonstructural carbohydrates (TNC) which is the sum of soluble carbohydrates and insoluble starch. The effects of CO2 enriched air on TNC during the ante meridiem (between midnight and 12 noon) photoperiod were determined using near infrared reflectance spectroscopy (NIRS). The effects of CO2 enriched air on turfgrass quality during the ante meridiem photoperiod were determined using normalized difference vegetative index (NDVI) chlorophyll measurements. Disease and visual quality differences amongst treatments or locations were measured on an incidental basis. No significance occurred within the 2006 and 2007 TNC or NDVI analysis for differences amongst treatments. 2006 average TNC for shoots were 24.8, 20.1, and 28.5 mg g [superscript minus]1 of tissue for the 363, 692, and 891 ppm CO2 levels, respectively. 2006 average NDVI for shoots were 7.2, 7.3, and 7.3 for the 363, 692, and 891 ppm CO2 levels, respectively. 2007 average TNC for shoots were 25.6, 18.9, and 23.1 mg g [superscript minus]1 of tissue for the 451, 716, and 1076 ppm CO2 levels, respectively. 2007 average NDVI for shoots were 7.9, 8.0, and 8.0 for the 451, 716, and 1076 ppm CO2 levels, respectively. All results were analyzed at 0.05 probability level within SAS 9.1. No incidence of disease or visual quality differences among treatments or locations occurred.

Download or read book Physiological Biochemical and Molecular Factors Associated with Heat Tolerance in Bentgrass Agrostis Spp written by Yan Xu and published by . This book was released on 2010 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: High temperature is a major factor limiting the growth of cool-season plant species during summer. Understanding mechanisms of plant tolerance to high temperature would help develop effective management practices and heat-tolerant cultivars through breeding or biotechnology. This dissertation research explored physiological, biochemical and molecular mechanisms for improving heat tolerance in two bentgrass species, creeping bentgrass (Agrostis stolonifera L.), a widely used cool-season grass species on golf course tees and putting greens, and thermal rough bentgrass (Agrostis scabra Willd.) adapted to geothermal areas in Yellowstone National Park. The dissertation reports research in three main components. The first section compared differential heat-induced metabolism of hormones, proteins and metabolites between heat-sensitive creeping bentgrass and heat-tolerant A. scabra. Based on the findings that heat tolerance of bentgrass was associated with changes in stress-related hormone levels, the effects of foliar-applied hormone or hormone inhibitors on creeping bentgrass to enhance heat tolerance were further studied. Results from both growth chamber and field studies confirmed the effectiveness of applying hormones or hormone-based plant growth regulators on alleviating heat injuries in creeping bentgrass. In the last part of the dissertation, a few transgenic creeping bentgrass lines with improved heat tolerance were characterized. These transgenic lines carry a gene (ipt) controlling cytokinin synthesis. Increased ipt gene expression and cytokinin levels were confirmed and changes in morphological and physiological traits of the plants were examined. Genome-wide protein responses to the addition of the gene and their association with heat tolerance were discussed. The results indicated that transformation with the ipt gene induced protein changes involved in multiple functional groups, mainly in energy, protein destination and storage, and disease/defense categories in both leaves and roots of creeping bentgrass, thus cytokinins may have regulatory roles in multiple metabolic pathways for heat tolerance. Taken together, these studies suggest summer performance of creeping bentgrass may be improved by properly applying hormone-based plant growth regulators or biostimulants, and incorporating molecular markers developed from heat- and/or hormone-responsive proteins and metabolites may facilitate selection of heat-tolerant creeping bentgrass cultivars.

Download or read book Creeping Bentgrass Agrostis Stoloniferous L Var Palustris Huds Microclimate and Physiological Responses to Induced Surface and Subsurface Air Movement and Increased Soil Carbon Dioxide Levels in a Heat Stress Environment written by Ian Rex Rodriguez and published by . This book was released on 2003 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Plant Growth Regulators on Creeping Bentgrass and Bentgrass Growth and Health During Heat Salt and Combined Heat and Salt Stress written by Arly Marie Drake and published by . This book was released on 2019 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: However, at times it is subjected to environmental stresses such as heat and salt. In field settings plants are often subjected to more than one stress at a time and studying stresses independently is likely insufficient. These stresses can affect plant hormone levels and, in turn, plant hormone levels can affect how well the plant tolerates stress. There were two experiments conducted. In the first experiment creeping bentgrass was transplanted into hydroponics systems in two different growth chambers. One chamber was set to have day and night time temperatures of 35 and 30-degrees Celsius, respectively. The other was set to have a day and night time temperatures of 25 and 20-degrees, respectively. Within each chamber one block received a 50 mM sodium chloride (NaCl) treatment and the other did not. Creeping bentgrass (Agrostis stolonifera L.) is a turfgrass species that is widely used on golf courses throughout the United States. It can withstand extremely low mowing heights and can provide a dense cover making it an ideal species for low cut areas of the golf course. The stress treatments were applied for 14 days. The experiment was repeated four times. Results of the first experiment indicated that the treatments were sufficient to negatively affect creeping bentgrass growth and health as indicated by fresh shoot and root weights, tillering, electrolyte leakage and total chlorophyll content (TCC). There were significant interactions between temperature and salt level detected for shoot and root weights and electrolyte leakage. Plants that were exposed to both heat and salt stress were more negatively affected than plants exposed to either heat or salt stress alone for all metrics except for tillering. The presence of NaCl reduced tillering regardless of temperature regime. In the second experiment plants were treated the same, but plant growth regulator (PGR) treatments were also applied. The second experiment was repeated six times and PGR treatments were re-randomized within the block each time. The PGR treatments consisted of two different gibberellin (GA) synthesis-inhibitor products, 2,4-dichlorophenoxy acid (2,4-D), two different rates of aminoethoxyvinylglycine (AVG), an ethylene synthesis suppressor, and plants that were not treated with a PGR. In addition to the aforementioned measurements of plant health and growth dry shoot and root weights were also measured. There were two significant interactions detected in the second experiment. For TCC there was a two-way interaction between temperature and PGR treatment and for electrolyte leakage there was a three-way interaction between temperature, salt level and PGR treatment. Combined heat and salt stress negatively affected all plants regardless of PGR treatment, but there were differences between PGR treatments. Plants treated with AVG performed better than the other PGR treatments. These plants had the highest shoot and root masses. Plants treated with GA-synthesis inhibitors had the lowest shoot and root masses as well as the lowest TCC when subjected to stress.

Download or read book Physiological Mechanisms of Creeping Bentgrass Agrostis Palustris L Tolerance to Summer Stress written by Xiaozhong Liu and published by . This book was released on 2000 with total page 532 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phytohormones Associated with a Bacterial Disease of Creeping Bentgrass Agrostis Stolonifera L Caused by Acidovorax Avenae Subsp Avena written by Sha Liu and published by . This book was released on 2016 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of CO2 and Nitrogen on Plant Response to Heat Stress written by Dan Wang and published by . This book was released on 2008 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: More intense, more frequent, and longer heat-waves are expected in the future due to global warming, both of which could have dramatic ecological impacts. It is necessary to determine how elevated CO2 and N affect plant responses to heat stress because atmospheric CO2 and N deposition will increase in the future. In the first project, we found thermotolerance of Pn in elevated (vs. ambient) CO2 increased in C3, but decreased in C4 (especially) and CAM (high growth temperature only), species. In contrast, elevated CO2 decreased electron transport in 10-of-11 species. High CO2 decreased gst (stomatal conductance) in 5 of 9 species, but stomatal limitations to Pn increased during heat stress in only 2 cool-season C3 species. Thus, benefits of elevated CO2 to photosynthesis at normal temperatures may be partly offset by negative effects during stress, especially for C4 species, so effects of elevated CO2 on acute heat tolerance may contribute to future changes in plant productivity, distribution, and diversity. The second project showed that effects of elevated CO2 on plant tolerance to heat stress are also dependent on N availability. Negative effects of high CO2 were associated with decreased CE (carboxylation efficiency) and rubisco activase (except high-N barley) and HSPs (especially HSP70). My meta-analysis results showed that elevated CO2 affects plant physiology and growth to varying degrees under different temperature regimes. The field study examined the effects of N availability on plant response to heat-stress (HS) treatment in naturally-occurring vegetation. The results indicated that increasing nitrogen (N) availability will likely impact plant responses to heat stress, and thus carbon (C) sequestration in terrestrial ecosystems, which suggests that heat waves, though transient, could have significant effects on plants, communities, and ecosystem N cycling, and N can influence the effect of heat waves.

Download or read book The Effect of Heat Stress on Aspects of Carbohydrate and Nitrogen Metabolism in Agrostis Cynodon and Poa Species written by John Edward Kaufmann and published by . This book was released on 1973 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Altered Assimilate Allocation and Partitioning Due to PCGA2 OXIDASE Overexpression on the Growth and Performance of Creeping Bentgrass Agrostis Stolonifera L in Full Sun and Reduced Light written by Aneta Karolina Studzinska and published by . This book was released on 2011 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Creeping bentgrass (Agrostis stolonifera L.) is a species commonly used in high maintenance turf areas. When grown under shade conditions, A. stolonifera becomes thin, elongated, and looses stem and root mass which ultimately leads to loss of turfgrass coverage. These responses to light stimuli are mediated, in part, by phytohormones, gibberellins. Suppression of gibberellin levels by overexpression of genes involved in their catabolism has been proven to successfully control plant stature. Gibberellin suppression also alters plant morphology and photosynthetic characteristics. The objective of this study was to determine the effect of runner bean (Phaseolus coccineus) GA2ox gene (PcGA2ox) overexpression (which increases gibberellin catabolism) on creeping bentgrass quality and performance under various light conditions and intense, short mowing height. GA2ox overexpression resulted in superior quality of Ax6549 under all shade treatments by delaying the decline of its color and coverage. Photosynthetic characterization indicated higher photosynthate supply per leaf area unit and enhanced low light use efficiency as potential factors associated with superior performance of Ax6549 under reduced light conditions. However, growth analysis data indicated lower growth efficiency and leaf productivity in Ax6549. Although this appeared to be contradictory to data obtained through photosynthetic characterization, this contradiction could be explained by increased self shading in Ax6549 due to greater leaf width and having a more horizontal leaf orientation. Morphological data did not help clarify the methods of improved performance of Ax6549 under shaded conditions. Whole canopy photosynthetic measurements performed at different cutting heights are likely needed to further explain the incongruities between photosynthetic and growth analysis data.

Download or read book Some Effects of Supraoptimal Temperatures Upon Creeping Bentgrass Agrostis Palustris Huds written by Dale Thomas Duff and published by . This book was released on 1967 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Elevated CO2 Concentration Improves Heat Tolerant Ability in Crops written by Ayman EL Sabagh and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The rising concentration of atmospheric carbon dioxide (aCO2) and increasing temperature are the main reasons for climate change, which are significantly affecting crop production systems in this world. However, the elevated carbon dioxide (CO2) concentration can improve the growth and development of crop plants by increasing photosynthetic rate (higher availability of photoassimilates). The combined effects of elevated CO2 (eCO2) and temperature on crop growth and carbon metabolism are not adequately recognized, while both eCO2 and temperature triggered noteworthy changes in crop production. Therefore, to increase crop yields, it is important to identify the physiological mechanisms and genetic traits of crop plants which play a vital role in stress tolerance under the prevailing conditions. The eCO2 and temperature stress effects on physiological aspects as well as biochemical profile to characterize genotypes that differ in their response to stress conditions. The aim of this review is directed the open-top cavities to regulate the properties like physiological, biochemical, and yield of crops under increasing aCO2, and temperature. Overall, the extent of the effect of eCO2 and temperature response to biochemical components and antioxidants remains unclear, and therefore further studies are required to promote an unperturbed production system.

Download or read book Mechanisms of Polyamine Induced Abiotic Stress Tolerance in Creeping Bentgrass Agrostis Stolonifera written by Yingmei Ma and published by . This book was released on 2017 with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Whole plant Carbon Relations and Root Respiration Associated with Root Tolerance to High Soil Temperature for Agrostis Grasses written by Eric M. Lyons and published by . This book was released on 2007 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plant tolerance to high soil temperature may be related to the adjustment in carbon production and utilization. The objective of this study was to determine changes in whole-plant carbon balance and root respiration rate in relation to root tolerance to high soil temperature for two Agrostis grass species varying in heat tolerance. Plant tolerance to high soil temperature was compared between Agrostis scabra, a thermal grass species adapted to chronic high-temperature soils in the geothermal areas in Yellowstone National Park, and creeping bentgrass (Agrostis stolonifera), a cultivated grass species adapted to cool climatic regions. Plant roots were exposed to low soil temperature (20 °C) or high soil temperature (37 °C) for 17 days in water baths placed in a controlled-environment growth chamber. Root biomass and cell membrane stability were determined to evaluate root thermotolerance of both species. Canopy photosynthetic rate (Pn), whole-plant respiration rate, root respiration rate, and total non-structural carbohydrate (TNC) content were measured to assess changes in carbon production and utilization in response to high soil temperature. Root biomass and cell membrane stability declined with increasing soil temperature, but the decline was much less for A. scabra than A. stolonifera, suggesting that roots of A. scabra were more tolerant to heat stress. Canopy Pn decreased and whole-plant respiration rate increased for A. stolonifera, but canopy Pn and respiration rate were unchanged for A. scabra in response to increasing soil temperature. After 17 days of high soil temperature treatment, A. stolonifera exhibited carbon deficit at the whole-plant level, whereas A. scabra maintained positive carbon gain. Root respiration of plants previously grown at 20 °C increased after a short-term treatment (24 h) at 37 °C, but the increase was significantly lower for A. scabra than for A. stolonifera. TNC content in roots did not show response to short-term (24 h) changes in temperature and did not exhibit species variations. Leaves of A. scabra, however, maintained TNC content under both low and high temperature regimes. Our results suggest that root thermotolerance of cool-season grasses could be related to the maintenance of positive whole-plant carbon balance, and down-regulation of whole-plant and root respiration rates in response to increasing soil temperature.

Download or read book Creeping Bentgrass Management written by Peter H. Dernoeden and published by . This book was released on 2002 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Biostimulants on Creeping Bentgrass Agrostis Stolonifera and Post harvest Debris of American Ginseng Panax Quinquefolius on Soil Microbiology and Chemistry written by Ivan D. Samur and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The efficacy of biostimulants on turfgrass creeping bentgrass (A. stolonifera) were tested in lab and greenhouse growth conditions. Biostimulants with initial efficacy improving greenness and/or biomass in lab trials mainly improved the physiology of the plant. The novelty of this study is the exogenous foliar application of phycocyanin on turfgrass as well the evaluation of GABA, GB, and R. intraradices on different creeping bentgrass cultivars under non-stress conditions. However, biostimulants affected different parameters of turfgrasses affected by cultivar. Ilyonectria mors-panacis causes low levels of root rot of American ginseng (Panax quinquefolius) in non-replant soil, but high levels when ginseng is grown in previously planted soil with ginseng, which results in replant disease (Farh et al, 2018). This study clearly shows that post-harvest debris decay of ginseng introduces considerable material into soil that has at least short-term effects, such as those observed with soil bacterial populations.

Download or read book The Effect of Trinexapac Ethyl and Three Nitrogen Sources on Creeping Bentgrass Agrostis Stolonifera Grown Under Three Light Environments written by Edward John Nangle and published by . This book was released on 2008 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Shade stress on creeping bentgrass (Agrostis stolonifera) causes elongation of leaves, reduced energy availability for growth and lower levels of disease resistance resulting in poor quality putting surfaces. Decreased quantity or photosynthetic photon flux density (PPF) and quality or the red:far red light ratio (R:FR) of light affects the morphology of turfgrass plants by increasing production of giberellic acid and reducing available non-structural carbohydrates. The object of the study was to determine which source of nitrogen (N) is best suited to retaining turfgrass quality in shade and to see if the plant growth regulator trinexapac-ethyl [4-(cyclopropyl-[alpha]-hydroxy-methylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (TE) (Syngenta AG, Switzerland) can improve density and combat the loss of surface quality of bentgrass under tree shade. Field studies were conducted on 'Penncross' creeping bentgrass (Agrostis stolonifera) in Columbus, in 2006, and 2007. Under three light environments: full sun (FS), reduced R:FR (DS), and reduced PPF (NS). Light reduction was>90% in both shade areas and the R:FR ratio was .38 in the DS area, 1.28 in NS, and 1.29 in FS. The three N treatments included (NH2)2CO, Ca(NO3)2 and (NH4)2SO4 foliarly applied weekly at a rate of 0.43g m-2 with or without TE applied bi-weekly at 0.3975 L ha-1. Chlorophyll content, along with non-structural carbohydrates, flavonoids, turf canopy color, dry matter and canopy densities were measured. There were no differences in soluble carbohydrate levels between treatments. Chlorophyll levels varied between TE treated and non-treated areas. Applications of (NH2)2CO consistently resulted in higher content of N15 in turfgrass plants also but there was no effect in nitrogen uptake kinetics due to light environment differences. TE had a negative impact on quantities of flavonoids. There was variation between the N treatments in relation to dry matter and carbohydrate content. (NH2)2CO in combination with TE provided the best visual quality surface as the season progressed. TE was effective in reduced PPF conditions and R:FR conditions which would indicate it as a possible product for use in shade management of creeping bentgrass Agrostis stolonifera. It was equally efficient in both light environments suggesting that prior shade research using NS is relevant to shade management in private industry. There was not a strong indication as to a preferred source of N.(NH2)2CO had positive impacts on total chlorophyll content.

Download or read book Biotechnology and Sustainable Agriculture 2006 and Beyond written by Zhihong Xu and published by Springer. This book was released on 2010-10-19 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This timely work is a collection of papers presented at the XIth international congress of the International Association of Plant Tissue Culture & Biotechnology. It continues the tradition of the IAPTC&B in publishing the proceedings of its congresses. The work is an up-to-date report on the most significant advances in plant tissue culture and biotechnology as presented by leading international scientists. It will be crucial reading for agricultural scientists, among others.