Download or read book Mowing and Light weight Rolling of Creeping Bentgrass Agrostis Stolonifera L Putting Greens During Summer Heat Stress Periods in the Transition Zone written by and published by . This book was released on 2006 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: A major challenge for golf course superintendents in the transition zone is to manage Agrostis stolonifera L. (creeping bentgrass) putting greens during heat stress periods of June, July, and August. In 2004 and 2005, a study was conducted to compare the effects of alternating rolling and mowing with traditional methods of everyday mowing on the green speed, turf quality, and disease occurrence creeping bentgrass putting greens in the transition zone. Treatments consisted of mowing six days week−1 without rolling, mowing six days week−1 with rolling three days week−1, and mowing three days week−1 alternating with rolling three days week−. Visual quality ratings for treatment effects determined a treatment and time interaction, which showed that alternating mowing with rolling had no significant change in turf quality throughout the study. In addition, mowing everyday maintained as high of quality throughout two months, but not at three months; while, mowing with rolling had significant decreases in quality by two months. There was no significance noted for disease incidence or root length among treatments or locations. Green speeds were statistically different for many of the collection dates for all locations. However, these speeds were only realistically for only 4 of 37 collection dates. Green speeds must exceed 15.2 centimeters of difference before the average golfer can distinguish a difference. A partial budgeting analysis was implemented to understand the economic effects as well. A mail survey was conducted in January 2006 to determine the standard mowing and rolling practices for golf courses in Tennessee, and it had a 37.5 percent response rate. A partial budgeting analysis was performed to determine the additional costs or savings generated by comparing mowing six days week−1, mowing six days week−1 with rolling three days week−1, and alternating mowing with rolling three days week−1. Adding rolling three days week−1 to a program of mowing six days week−1 increased overall total cost as expected for both triplex and walk behind mowers over all golf course types. However, alternating mowing with rolling three days week−1 has the potential to reduce total cost, particularly for courses using walk behind mowers, compared to only mowing six days week−1.

Download or read book Physiological Effects of Low Mowing Heights Rolling and Foot Traffic on Creeping Bentgrass Putting Greens written by Joseph Ronald Young and published by . This book was released on 2013 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Golf course superintendents are managing creeping bentgrass ( Agrostis stolonifera L.) putting greens throughout the transition zone where temperatures can exceed optimum levels for consecutive days in the summer. The stress of creeping bentgrass associated with these supraoptimal temperatures has been well documented, but the management practices implemented on putting greens to increase green speeds may exacerbate these environmental stresses. To date, the physiological effects of these management practices in combination have not been evaluated for putting green turf. The objective of this dissertation project was to determine the effect of mowing heights, light-weight rolling, and foot traffic on performance and physiological parameters of 'SR 1020' and 'Penn G2' creeping bentgrass. Both above and below ground performance characteristics were evaluated in this project including: wear tolerance, turf quality, turf coverage, turf color, rooting characteristics, ball roll distance, ball mark severity, and ball mark recovery. Physiological data were collected with a custom photosynthesis chamber, and carbohydrate analysis was performed for all mowing and rolling treatments. Individual carbohydrates (total ethanol soluble sugars, glucose, sucrose, fructans, and average degree of polymerization) were determined for foliage, crown, and root material of each sample. Both performance characteristics and physiological parameters reached poorest levels in July or August each year as environmental stresses increased. Plots maintained at higher mowing heights and reduced rolling frequencies maintained better wear tolerance, turf quality, coverage, and color compared to lower mowing heights with frequent rolling. Net photosynthesis increased slightly as mowing heights were increased, but few significant differences were observed for these treatment combinations. Few consistent differences were observed for carbohydrate analysis with lower mowing heights or increased rolling frequencies, but increased mowing height generally resulted in higher carbohydrate concentrations in foliage and crown material following heat stress. Ball mark severity was rarely affected by these treatment combinations, but increased rolling frequencies increased maximum ball mark injury and extended recovery time. Fewer significant differences were observed for these parameters compared to initial expectations, but increased mowing heights and reduced rolling frequencies generally created healthier turf.

Download or read book Creeping Bentgrass Management written by Peter H. Dernoeden and published by John Wiley & Sons. This book was released on 2000-07-15 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Creeping Bentgrass Management presents a difficult management problem throughout the summer season. This complex dilemma is related to numerous and often interrelated factors such as: extreme air and soil temperatures, drought or excessively wet soils, dense thatch or organic mats, mechanical and other physical stresses, improper management practices, the misuse of chemicals, and other physical stresses. The goal of this useful manual--complete with helpful color photographs--is to give golf course superintendents practical tools to better understand the many stress factors that contribute to the creeping bentgrass decline complex. It will help you pinpoint problems, and implement cultural and chemical solutions to maintain the integrity of your course.

Download or read book Biology and Pathogenicity Factors of Rutstroemia Floccosum and the Effects of Lightweight Rolling on Dollar Spot Disease Incidence in Creeping Bentgrass Putting Greens written by Paul Ryan Giordano and published by . This book was released on 2010 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Creeping Bentgrass Management written by Peter H. Dernoeden and published by CRC Press. This book was released on 2012-06-04 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Creeping bentgrass is considered the premier turfgrass species grown on golf courses, and there is a growing demand for an understanding of its maintenance and management practices. Still the only comprehensive reference on the subject, Creeping Bentgrass Management, Second Edition helps you identify the factors that contribute to summer bentgrass

Download or read book Effects of ET Irrigation Mowing and Wetting Agent on a Putting Green written by Rodney Tocco and published by LAP Lambert Academic Publishing. This book was released on 2015-08-12 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: The demand for optimum Agrostis stolonifera var. palustris (creeping bentgrass) putting greens requires golf courses' to manage inputs closely. Challenges include low mowing heights, heat stress, traffic, and viable irrigation sources to manage creeping bentgrass. A factorial field experiment was designed on a Crenshaw putting green during the summers of 2010-2012 in East Lansing, MI comparing irrigation and mowing frequencies with and without a wetting agent. Daily irrigation replenishment of 30, 60, and 90% evapotranspiration (ET) measurements were compared for irrigation use efficacy while maintaining quality playing conditions and turfgrass health. Daily single and double mowing frequencies were compared for long-term aesthetics, pest populations, and playability when mowed at 0.3175 cm (0.125 in). Monthly applications of a wetting agent (Revolution(r)) were compared to untreated plots. Playability and overall aesthetics were characterized by weekly measurements of ball roll distance, percent volumetric water content (%VWC), and visual quality ratings (1-9). Annual soil measurements included water drop penetration (WDP) test and total microbial biomass (TMB).

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 The Effect of Brushing on Creeping Bentgrass Putting Green Quality written by Chenchen Gu and published by . This book was released on 2016 with total page 35 pages. Available in PDF, EPUB and Kindle. Book excerpt: Brushing is a daily practice method for golf course turfgrass maintenance which is done to stand the turfgrass plant prior to being cut. Creeping bentgrass (Agrostis stolonifera L.) is the primary turfgrass species used on golf course putting greens in temperate regions, but it has a prostrate growth habit. Brushing promotes vertically oriented leaf tissue, which helps the plant tolerate lower mowing heights. Vertical growth promotes higher shoot density, which helps reduce the competitive ability of some weeds. However, different frequency of brushing could lead to variation in the structure of the turfgrass leaves. The mechanical or abrasive nature of brushing potentially can cause physiological injury to the turfgrass plant. The objectives of this research are to evaluate the variation of the green speed as well as to quantify the fluctuations in physiological benefits or stress and to investigate the morphological changes due to brushing creeping bentgrass putting greens throughout the growing season. The two-year experiment was conducted on a standard `Penncross’ creeping bentgrass putting green on native soil located at the Ohio Turfgrass Foundation Research and Education Facility. For the first three months of the first year, the treatments consisted of two different brushing frequencies, brushing once a week and brushing three times a week with brushing unit set at 2.54 mm, compared to an untreated control. However, there wert no significant differences among those treatments. Therefore we adjusted our treatments to brushing three times a week or brushing five times a week with brushing unit set at 0.00 mm and continued the treatments in the second year of research. We found improvement in turf leaf texture and faster green speed with brushing while the variation of photochemical efficiency was not significant until the maximum temperature got lower than 15°C. In 2014 we observed a thinner leaf blade that appeared to have less leaf moisture in the brushed treatment compared to the untreated control. In 2015 we had four treatment which consisted double cut, double cut with brushing three times a week, double cut with brushing five times a week and untreated control which was single cut. We found increased green speed with all brushing treatments and a significant reduction in the amount of cuticle wax where double cutting had the greatest effect (P=0.05) while no physiological stress was indicated by measuring photochemical efficiency.

Download or read book Rapid Conversion of Golf Course Turf to Glyphosate resistant Creeping Bentgrass written by Lukas Aryn Dant and published by . This book was released on 2005 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Creeping bentgrass (Agrostis stolonifera L.) is grown on golf course putting greens and its use as fairway turf is becoming more common. Creeping bentgrass cultivars tolerant to the herbicide glyphosate [N-(phosphonomethyl)glycine] have recently been developed. The ability to control weeds by the application of a nonselective herbicide, such as glyphosate, would ease overall turfgrass management. The conversion of existing putting greens and fairways to glyphosate-resistant creeping bentgrass is an option that many golf course superintendents are likely to consider. However, the conversion of existing turf to a more desirable species or cultivar is costly and would require the golf course to close for a considerable period of time. The objective of these field experiments was to speed the conversion of previously established putting greens and fairways to glyphosate-resistant creeping bentgrass. The best timing for glyphosate application to remove competition from existing grasses was researched on existing putting greens and fairways. Research was also conducted to study the effect of the following factors on conversion of existing putting greens to glyphosate-resistant creeping bentgrass: (i) seeding date, (ii) seeding rate, (iii) surface preparation method, (iv) mowing practices after seedling germination, and (v) N fertility. The best timing for glyphosate application to remove competition from existing turf was before seeding or shortly after seeding. Golf course putting green conversion to glyphosate-resistant creeping bentgrass was most rapid when seed was sown in late summer at 7.3 g m−2. All surface preparation methods resulted in similar turf cover, but some methods were less labor-intensive and caused less disruption to the putting green surface. Putting green conversion was most rapid when seedlings were mowed for the first time at 6.4 mm and glyphosate-resistant creeping bentgrass was permitted to reach approximately 100% cover before lowering the mowing height at a rate of 0.76 mm wk−1. No differences were observed between N fertility rates of 1.2 and 2.4 g m−2 wk−1. The results of these experiments suggest that successful conversion of golf course turf to glyphosate-resistant creeping bentgrass can occur with minimal interruption to golf play.

Download or read book Potassium Fertilization and Stress Tolerance of Intensely Managed Creeping Bentgrass Putting Greens written by Benjamin Brace and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Potassium (K) requirement of creeping bentgrass putting greens is a highly-debated topic. Recent studies evaluating K fertilization requirements contend its importance, but golf course superintendents still apply it regularly, their justification being that golf course putting greens established on sand-based rootzones have limited K retention and that sufficiency is crucial during stress periods. A two-year study was conducted to quantify Penn A- and G-series creeping bentgrass (Agrostis stolonifera L.) putting green performance and stress-tolerance response to soluble K fertilizer rate and/or frequency, to develop K fertilization guidelines and identify a critical K deficiency thresholds. Foliar applications of KCl (0-0-60) were made on 7- or 14-day intervals to supply 0, 15, 30, or 45 kg K2O ha-1 per growing month. Three putting greens were maintained under an intense double-cutting, rolling, and limited soil moisture management regime and in the second season height-of-cut was lowered and management intensified to simulate tournament conditions for a three-week period. Monthly clipping yields and associated leaf nutrient status indicated optimal vigor and nutrient sufficiency for throughout most of the study. Mehlich-III soil analysis revealed concentrations below recommended levels, but deficiency symptoms were never seen. Canopy density and color, measured using multispectral radiometers, were not influenced by the K fertilizer treatments. Leaf water content was influenced more by environmental conditions than K fertilizer treatment. Under simulated duration of extreme drought and wear stress, K fertilizer treatments did not benefit turfgrass canopy density or survival.

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 How to Build a Putting Green written by S. Barry Hamdani and published by Lulu.com. This book was released on 2007-02-01 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Backyard putting greens construction, maintenance and cost. This detailed book covers everything you need to know about grass and synthetic greens. Demonstrates the difference in USGA standard greens and backyard putting greens.

Download or read book Influence of Temperature on Germination of Bentgrass Cultivars and Cultural Practices on Establishment of Creeping Bentgrass written by Devon E Carroll and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Winterkill of turfgrasses on golf course putting greens is highly unpredictable and problematic for superintendents in northern climates, specifically in the Northeastern United States. Harsh winters in the 2013-14 and 2014-15 seasons left many superintendents facing the difficult challenge of trying to recover from turf loss at a time coinciding with the opening of golf courses for play. Creeping bentgrass (Agrostis stolonifera L.; CBG) putting greens are commonly infested with annual bluegrass (Poa annua L.; ABG). Annual bluegrass is known to be an aggressive weed and a species that is difficult to eradicate. Over time, ABG can become the dominant and preferred species to maintain on putting greens. This dominance of ABG in cold climates can become problematic due to the susceptibility of the species to temperature extremes when compared to CBG. In the event of winterkill, superintendents may discover turf loss in sporadic voids or possibly the loss of entire ABG putting greens after snow melt that occurs. If winterkill occurs, re-establishment of the putting surface via CBG seed or sod may be required. Seeding is often the preferred method of recovery, but temperatures in the early spring generally are considered suboptimal for germination. Limited information is available on the influence of suboptimal temperatures on bentgrass germination. The evaluation of CBG cultivar performance (e.g., germination) at low temperatures would be valuable to superintendents seeding in early spring. Additionally, information on effective methods of cultivation, nitrogen (N) fertilization, and seeding rates could optimize establishment of CBG and reduce losses of golf course revenue due to course closure. The objectives of this study were to: 1) determine the impact of suboptimal temperatures on bentgrass cultivar germination; and 2) elucidate the influence of cultivation methods, starter fertilizer rate, and seeding rate on the establishment of CBG. Differences in germination among cultivars were observed when seed was incubated at 10C. Samples of Pure Select, Greentime, Crystal BlueLinks, and Penn A-4 had the highest germination at 10C when incubated in the presence or absence of light. Mackenzie, PLS, Tyee, and Villa exhibited the lowest germination at 10C. Germinability at low temperatures should be considered as a factor in cultivar selection for early spring seeding at suboptimal temperatures.Field experiments indicated that seeding at a rate of 73 kg seed ha-1 and fertilizing at a rate of 73 kg N ha-1 increases seedling vigor and percent ground cover compared to lower seeding and N rates. Slicing was an effective method of cultivation. Putting greens cultivated by slicing alone, slicing + 13-mm hollow tine aeration, and slicing + 6-mm hollow tine aeration generally showed similar seedling vigor and percent cover, indicating that superintendents could use slicing alone to save money and time on hollow tine aeration. These cultivation practices, combined with careful cultivar selection, can optimize early spring seeding and may result in quicker recovery where winterkill occurs.

Download or read book The Effects of Mechanically Induced Air Movement on the Temperature Leaf Water Potential and Soil Moisture Percentage of Creeping Bentgrass Agrostis Stolonifera L Golf Greens written by Gene Rupert Taylor and published by . This book was released on 1995 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of Pigment containing Products on Creeping Bentgrass Agrostis Stolonifera L Var Palustris Huds Performance written by James Richard Gann and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Golf courses continue to explore all options for relief of summer stress on bentgrass [Agrostis stolonifera L. var palustris (Huds.)] putting greens. The use of colorants and other pigment-containing products has recently been suggested as a means of relieving this stress by reducing temperatures and respiration, and increasing photosynthesis. Research supporting these claims is limited, especially on bentgrass putting greens located in stressful environments. The objective of this experiment was therefore to investigate the impacts of pigment-containing products on turfgrass physiology during hot and humid summer months in the Southeastern USA. Four pigment-containing products were selected for the two 2012 summer field studies: Turf Screen (a combination of zinc oxide and titanium dioxide), PAR and Foursome (copper-based pigments), and a paint designed for dormant turfgrass throughout the winter months. Products were applied weekly for ten weeks. Two of the products, Turf Screen and PAR, were also used in two 10 day growth chamber studies to evaluate their effects on bentgrass plugs under stressful high temperatures. In field studies, lower carbon dioxide exchange rates (CER) were measured in untreated turf compared to Turf Screen, PAR, Foursome and the paint, indicating that these products reduced photosynthesis. In both studies, the paint had the highest CER of any treatment. Turf Screen and PAR performed similarly in both studies (0.182 and 0.118 μmol CO2 cm-2 s-1 in study one, 0.090 and 0.091 in study two). In study two, evaporation rates of untreated plots averaged 1.00 μmol H2O cm-2 s-1, which was significantly higher than Turf Screen at -9.10 μmol H2O cm-2 s-1. None of the tested products lowered canopy temperature, and treated turf plots often exhibited significantly higher temperatures (~1.5°F or 1.0°C) than the untreated controls. In study one, the untreated control had higher normalized difference vegetation index (NDVI) values than PAR, Turf Screen, and the paint throughout the summer. Differences in NDVI were not observed between Turf Screen, PAR, and Foursome in either study. Visual quality of turf treated with Turf Screen, PAR, and Foursome was similar to the untreated control in both studies. Images analyzed with the WinRHIZO program to calculate percent cover provided data consistent with the visual turfgrass quality ratings. Products had no significant effects on root mass. Tissue analysis showed Turf Screen treated foliage had higher zinc concentrations in both studies, averaging 911 ppm compared to 88 ppm for the untreated control. Soil zinc levels in Turf Screen treated plots were twice those of the other treatments in both studies. The paint treated turf had significantly higher tissue copper concentrations in both studies, averaging 155 ppm compared to the other treatments, which averaged 61 ppm. In growth chamber studies, CER was significantly lower in the unstressed control (35/24oC) at -1.15 compared to Turf Screen at 1.53, PAR at 0.67, and the stressed control (28/22oC) at 1.12 μmol CO2 cm-2 s-1 in study one. Positive CER values indicate that respiration rates exceeded photosynthetic rates in these pots. The unstressed control had significantly higher evaporation rates compared to Turf Screen, PAR, and the stressed control in study one. The stressed control, Turf Screen, and PAR had significantly lower Fv/Fm values compared to the unstressed control in both studies. A significant reduction in the transmission of photosynthetically active radiation (400-700 nm) occurred when products were applied to transparent acrylic sheets. PAR and Foursome had least impact on the transmission of (PAR) wavelengths by only reducing ~20%. Turf Screen (39%) and the paint (46%) had the largest reductions. Microscopy images visualized the specific interactions between products and leaf blades. While Turf Screen (higher viscosity) remained on the leaf surface and covered the stomata, pigments such as PAR (lower viscosity) entered the leaf via stomata. Higher CER for treated turf in field study two indicates net photosynthesis is reduced when these products are applied. Higher evaporation rates for the untreated in field study two indicate that transpiration is also being affected by these products. Spectroradiometer data show a significant reduction in the transmission of photosynthetically active radiation when products are applied. In summary, these products failed to significantly enhance any plant processes normally associated with improved turf health and quality. On the contrary, products appeared to disrupt the plant's ability to cool itself through transpiration. The significant increases in heavy metal concentrations such as zinc and copper should also be considered, especially with long-term use.

Download or read book Non target Effects of Strobilurin Fungicide Applications on Creeping Bentgrass Putting Greens During Summer Stress written by Jesse J. Benelli and published by . This book was released on 2013 with total page 117 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous research has indicated that strobilurin fungicide applications may improve summer stress tolerance of creeping bentgrass (Agrostis stolonifera L.) putting greens. In this experiment, strobilurin fungicides were integrated within a summer fungicide program to evaluate disease severity and plant physiological effects. Fungicide programs were applied on a 'Dominant Southern' creeping bentgrass putting green; all of which consisted of five fungicide spray applications from June to August during 2011 and 2012. The 2nd and 5th application in each program consisted of a strobilurin fungicide. Strobilurin fungicides evaluated included pyraclostrobin, azoxystrobin, fluoxastrobin, or trifloxystrobin. The remaining fungicide applications were identical across programs. Measurements of visual quality, spectral reflectance, turfgrass cover, rooting characteristics, and disease severity were collected. The non-treated control was similar to treated plots in all parameters in 2011, and until 42 and 56 days after initial treatment (DAIT) the following year. At this time, fungicide programs began to exhibit greater visual quality, turfgrass cover, and spectral reflectance compared to the non-treated control. Differences in physiological effects coincided with the first observation of brown patch (Rhizoctonia Solani Kühn) in the experimental area. These data suggest that strobilurin fungicides exhibit excellent efficacy for disease control during summer, and that direct physiological effects may be transient and observable over the long term. A 2-year field experiment was conducted to determine if applications of pyraclostrobin, azoxystrobin, fluoxastrobin, and trifloxystrobin could improve plant physiological effects of a 'Dominant Southern' creeping bentgrass putting green in the absence of visible foliar disease. Experimental units were arranged in a split-plot randomized complete block design. A fungicide mixture containing chlorothalonil and iprodione and a no fungicide treatment served as the whole-plots. Chlorothalonil and iprodione were applied at 14-day intervals. Sub-plots were treated with strobilurin fungicides (azoxystrobin, pyraclostrobin, fluoxastrobin, and trifloxystrobin) and a non-treated control. Sub-plots were applied at 14-day intervals. Neither differences in disease severity nor any physiological effect was observed on any assessment date over the course of two years. The results of this experiment suggest that while strobilurin fungicides perform well for disease control, detectable plant physiological effects under field conditions were limited.

Download or read book Creeping Bentgrass Agrostis Stolonifera L Putting Green Establishment Strategies written by Eric Christopher Chestnut and published by . This book was released on 2018 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: