2017 National Turfgrass Evaluation Program Perennial Ryegrass Test: 2018 Data

More than 100 entries of perennial ryegrass were evaluated in the perennial ryegrass National Turfgrass Evaluation Program (NTEP) study in Manhattan, KS, in 2018. A broad variation occurred among entries. Several entries consistently ranked in the top 10 in quality from month to month

Evaluating the Salinity Tolerance of Bermudagrass Cultivars and Experimental Selections

Bermudagrass is a highly productive, warm-season, perennial grass that has been grown in the United States for turfgrass, forage, pasture, rangeland, and roadside use. Many production and reclamation sites across the United States are affected by soil salinity issues. Identification of bermudagrasses with improved salinity tolerance is important for the successful implementation of bermudagrass production and reclamation of salt affected sites and/or with use of saline irrigation water. In this project, the relative salinity tolerance of seven clonal-type bermudagrasses and 10 seeded bermudagrasses, including industry standards and Oklahoma State University (OSU) experimental lines, were determined. The newly developed experimental lines and newly released cultivars by Oklahoma State University that had shown improved cold hardiness and improved spring dead spot tolerance were included in the study. The experiment was conducted under a controlled environment with six replications of each treatment. Four salinity levels (0, 15, 30 and 45 dS m-1) were used to test the 17 bermudagrass entries, and the relative salinity tolerance among entries were determined by the normalized difference vegetation index (NDVI), digital image analysis (DIA), leaf firing (LF), turf quality (TQ), shoot dry weight (SW), shoot vertical growth (VG) and dark green color index (DGCI). Results indicated that there were variable responses to salinity stress amongst the entries studied. As salinity levels of the irrigation water increased, turf quality decreased and leaf firing increased. At the highest irrigation water salinity level (EC = 45 dS m-1), the canopy green leaf area as measured using DIA ranged from 3.07% to 24.72% and 4.97% to 16.11% in the clonal and seeded trials, respectively. Overall, �Princess 77� and experimental entry OKC1302 provided the highest level of performance in the seeded and clonal trials, respectively, at the 30 dS m-1 salinity level. The parameters LF, TQ, NDVI, DGCI, SW, VG, and DIA were all highly correlated with one another, indicating their usefulness as relative salinity tolerance measurements.Horticultur

Impact of Zoysiagrass and Tall Fescue Seed Mixtures on Brown Patch Severity

Earlier research has demonstrated that polystands of zoysiagrass and tall fescue can be established successfully, with the potential to provide a high-quality turfgrass stand with reduced inputs. Our objective was to determine whether mixing zoysiagrass with tall fescue will reduce brown patch severity while maintaining overall acceptable quality. Studies were established at the Rocky Ford Turfgrass Research Center in Manhattan, KS. In the split-plot design, natural infection by Rhizoctonia solani or a fungicide-treated control was the whole-plot treatment factor and species (tall fescue monostand and the zoysiagrass/tall fescue mixture) were subplots. During July and August 2016, when hot, humid weather triggers brown patch, excessive irrigation was applied to promote brown patch. Disease severity was measured by visual ratings and digital image analysis; number of infected leaves in each plot was recorded using a grid. The mixed stand then showed less plot area affected by brown patch disease compared to the monostand of tall fescue

Evaluating Zoysiagrass-Tall Fescue Mixtures in Kansas

Seeding zoysiagrass at 1 lb PLS/1,000 sq ft in June with subsequent seeding of tall fescue into established zoysiagrass in September at 8 lbs PLS/1,000 sq ft resulted in the best mixture of these two species

Evaluation of tall fescue-zoysiagrass polystands and new zoysiagrass genotypes for use in the transition zone

Doctor of PhilosophyDepartment of Horticulture and Natural ResourcesJack FryMegan KennellyZoysiagrasses (Zoysia spp.) use C4 metabolism and are more drought resistant than C3 grasses. However, the long dormancy period between autumn and spring limits the use of zoysiagrass by homeowners and professional turfgrass managers. In addition, large patch has become the primary pest on zoysiagrass, and improved cultivars with good cold hardiness and large patch resistance are needed in the transition zone. Tall fescue (Schedonorus arundinaceus Schreb), a C3 grass, is used frequently in Kansas due to its heat and drought tolerance compared to some other C3 grasses. However, brown patch (Rhizoctonia solani) is the main disease limiting its growth in summer. Alternatively, mixing zoysiagrass with tall fescue may help reduce brown patch incidence. The objective of these projects were to: (1) evaluate methods for establishing a perennial mixture of seeded zoysiagrass and tall fescue; (2) determine whether a zoysiagrass/ tall fescue polystand is less susceptible to brown patch and results in improved summer quality compared to a tall fescue monostand; and (3) evaluate experimental zoysiagrass genotypes to identify one or more potential new cultivars which have high quality and tolerance to cold and large patch. I found that polystands of zoysiagrass and tall fescue were most successfully established by seeding zoysiagrass at 49 kg ha-1 in June and tall fescue at 392 kg ha-1 in September into the established zoysiagrass sward. Polystand establishment was also superior at a 1.9 cm mowing height than a 5.1 cm mowing height. The resulting mixture resulted in improved turf color in late fall and early spring compared to a zoysiagrass monostand. In addition, using a zoysiagrass-tall fescue polystand reduced brown patch by up to 21% compared to a tall fescue monostand. In the zoysiagrass breeding project, I identified ten progeny out of sixty evaluated that had better tolerance to large patch (up to 40 % less plot area affected) and better quality compared to Meyer zoysiagrass, which is the standard cultivar used in the transition zone

Winter Survival of Experimental Bermudagrasses in the Upper Transition Zone

A winter with very cold temperatures in 2017–2018 allowed for good separation of standard and experimental bermudagrasses for freezing tolerance. When evaluated in May 2018, survival of commonly used cultivars was: Tifway, 0%; Latitude 36, 20%; Northbridge, 25%. Some experimental progeny had up to 98% winter survival on the same rating date

Evaluating Large Patch-Tolerant and Cold Hardy Zoysiagrass Germplasm in the Transition Zone

More than 2,800 zoysiagrass progeny, all having a single parent in common that exhibited tolerance to large patch, were evaluated in several transition zone states for quality characteristics and large patch tolerance. From these evaluations conducted over several years, 10 progeny have been identified for further evaluation that have good quality and large patch tolerance that is superior to Meyer zoysiagrass

Brown Patch Occurrence in a Zoysiagrass-Tall Fescue Polystand Compared to a Tall Fescue Monostand

Research has demonstrated that polystands of zoysiagrass and tall fescue can be established successfully, with the potential to provide a high quality turfgrass stand with reduced inputs. Our objective was to determine whether mixing zoysiagrass with tall fescue will reduce brown patch severity while maintaining overall accept­able quality. Studies were established at the Rocky Ford Turfgrass Research Center in Manhattan, KS. In the split-plot design, natural infection by Rhizoctonia solani or a fungicide-treated control was the whole plot treatment factor and species (tall fescue monostand and the zoysiagrass/tall fescue mixture) were subplots. During July and August 2016 and 2017, when hot, humid weather triggered brown patch, excessive irrigation was applied to promote brown patch. Disease severity was mea­sured by visual ratings and digital image analysis; number of leaves in each plot that were infected was recorded using a grid. The mixed stand then showed less plot area affected by brown patch disease compared to the monostand of tall fescue

Evaluating Zoysiagrass-Tall Fescue Mixtures in Kansas

Water conservation is increasingly important when selecting turfgrasses. Zoysiagrass (Zoysia japonica), a C4 grass, is more drought resistant than C3 grasses. However, there is some resistance to the use of zoysiagrass in lawns and golf courses due to its extended dormant period when turf is brown. The objective of this study was to evaluate mowing height, and tall fescue seeding rate and time for establishment of a mixed stand with seeded zoysiagrass. Seeding zoysiagrass and tall fescue together in June generally resulted in a less uniform mixture than seeding zoysiagrass in June and then seeding tall fescue in September. Tall fescue seeded in September at 8 lb of pure live seed (PLS)/1,000 ft2 resulted the most uniform mixture of the two species

Evaluating Large Patch-Tolerant and Cold Hardy Zoysiagrass Germplasm in the Transition Zone

A Zoysia japonica genotype, TAES 5645, that exhibited partial resistance to large patch in preliminary studies conducted by our collaborators at Texas A&M University, was used as a breeding parent at Texas A&M and crossed with 22 cold hardy zoysiagrasses, resulting in 2,858 progeny. These progeny were evaluated for cold hardiness and agronomic traits (establishment rate, overall quality, spring green up, leaf texture, and genetic color) in Manhattan, KS; West Lafayette, IN; and Dallas, TX; from 2012 to 2014. This report focuses on the Manhattan, KS, results. From this work, 60 progeny were identified for further evaluation in larger plots. In fall 2016, ‘Meyer’ (42% of plot area affected) had more large patch than all zoysiagrass progeny (0 to 23%). In spring 2017, Meyer had 33% large patch, higher than most progeny. Among this group of experimental zoysiagrasses, there appear to be promising progeny that have good winter hardiness, resistance to large patch, and improved turf quality characteristics. Data collection is ongoing