The Turfgrass Science team from the University of Minnesota was well-represented at this year’s ASA-CSSA-SSSA Annual Meeting held on November 10-13, 2019 in San Antonio, TX. Seven people gave oral presentations and five people presented posters. Additionally, congratulations go to two members of our group who placed in the graduate student oral presentation contests:
- Garett Heineck was awarded 2nd place for his oral presentation in the Genetics and Molecular Techniques section of the C5 Division.
- Ryan Schwab was awarded 3rd place for his oral presentation in the Golf Turf section of the C5 Division.
Below is a listing of all the oral presentations and posters along with links to the presentation abstracts and the poster PDF files.
Oral presentations
Increasing Competition in Perennial Ryegrass Selection Nurseries Bolsters Prediction Accuracy
Presented by Garett Heineck; co-authors Nancy Jo Ehlke, Kayla Altendorf and Eric Watkins
The success of a turf-type perennial ryegrass variety depends on both adequate turfgrass quality and economic seed yield. In most breeding programs, spaced plants are the initial unit of selection wherein observations of related individuals dictate selections of superior germplasm for further testing. As such, spaced plants must be predictive of both sward environments. This research explored the effectiveness of both standard (3 plants m-2) and competitive (23 plants m-2) spaced plant nurseries as selection environments using 20 turf-type entries. Seed production plots, turfgrass plots, and the two spaced-plant growing environments were tested at two locations in Minnesota in 2017 and 2018. Meaningful breeding targets for seed production were discovered using structural equation modeling (SEM). Traits important for superior turfgrass quality were determined through multiple regression across many rating dates. Results showed that winter survival was imperative to obtain optimum seed yield and turfgrass quality, albeit only to a certain extent. Seed yield was only affected when tiller survival was below 20% whereas turfgrass quality was impacted when tiller survival was much higher (<60%). The seed yield components fertile tiller number, spike yield, and fertility index (seed fill efficiency) were identified by the SEM as important breeding targets. Of these, fertility index in spaced plants was by far the most useful indicator of sward yield, especially in the competitive nursery, where rank correlations were substantial at both locations (rs = 0.52 and 0.81, P < 0.05). For turfgrass traits, genetic color and crown rust were the most important predictors of turfgrass quality. In this case, the competitive spaced plant design offered minor improvements of predictive ability compared to the standard environment. Overall, increased competition between spaced plants improved the predictive ability (rs) for seed production traits and while it offered only a small benefit for most turfgrass traits, it did not decrease predictive ability. Furthermore, the competitive design has a lower field space requirement and facilitates more efficient data collection for many traits compared to a standard design.
Wetting Agent Influence on Soil Water Repellency Parameters at Different Rootzone Temperatures
Presented by Ryan Schwab; co-authors Brian Horgan and Samuel Bauer
Wetting agents are commonly applied to golf turf to solve moisture issues. They may alter water retention in the rootzone as well as prevent localized dry spots by reducing the degree and persistence of soil water repellency. Reapplication is needed to maintain these functions; however, it is unclear how much environmental factors such as soil temperature and water volume from irrigation or rain events influence an ideal reapplication interval. The objective of this research was to test if a wetting agent, Cascade Plus, lost function when exposed to different soil temperatures over time. Creeping bentgrass (Agrostis stolonifera) plugs in conetainers were maintained at three soil temperature treatments (21.5, 28, and 34.5 °C) within porous heat baths. Water retention, water droplet penetration time (WDPT), critical moisture content, and the area below the WDPT-soil moisture curve were quantified 10, 20, and 30 days after a single Cascade Plus application. These soil water repellency parameters were compared across time points and to an untreated control. Preliminary results suggest that Cascade Plus may reduce all of the quantified soil water repellency parameters at all soil temperature exposure levels compared to an untreated control, and water retention measured gravimetrically was not a useful function to determine its efficacy. Results from this work will lead to a clearer understanding of environmental influence on wetting agent functions for more efficient reapplication programs.
Improving Our Approach on How We Analyze Turfgrasses for Tolerance to Foliar Shade
Presented by Dominic Petrella; co-author Eric Watkins
Turfgrass is often affected by foliar shade such as that from trees and shrubs. This type of shade results in reductions in light quantity and the ratio of red to far-red light (R:FR), both of which can decrease turfgrass quality. The conditions produced by foliar shade are quite variable in nature, and little to no information is available on common reductions in light intensity or commonly found R:FR ratios. A considerable amount of research has evaluated the effects of reduced light quantity on turfgrasses using neutral shade cloth and arbitrary reductions in light quantity; however, most of these studies have not addressed changes in R:FR. Experiments have been performed under real-world foliar shade, but a review of the literature indicated that light quantity is not always monitored and the R:FR ratio is rarely reported. The objective of this research was to evaluate changes in light quantity and the R:FR ratio under foliar shaded turfgrasses in St. Paul MN to better understand how we can approach improving tolerance to foliar shade. The results of a two year study indicate that we may be able to better understand foliar shade sites by 1) taking into account fluctuations in light intensity by collecting data every one minute, 2) examining the number of hours at given light intensities rather than only evaluating the daily light integral, and 3) monitoring R:FR in morning, solar noon, and in the evening.
Fine Fescues As Living Mulch in Minnesota Cropping Systems
Presented by Florence Sessoms; co-authors Eric Watkins, M. Scott Wells, Nancy Jo Ehlke, Dominic P. Petrella, Donn Vellekson and Alexander Hard
Unveiling Transcriptome Composition in Hexaploid Hard Fescue (Festuca brevipila) through Pacbio Isoform Sequencing
Presented by Yinjie Qiu; co-authors Cory Hirsch and Eric Watkins
Assessment of Tillering and Rhizomatous Growth in Strong Creeping Red Fescue
Presented by Nicole Mihelich; co-authors Dominic P. Petrella, Florence Sessoms, Laura M. Shannon and Eric Watkins
Natural Weed Suppression of Crabgrass Varies By Genotype and Field Management Practices
Presented by Jon Trappe; co-authors Eric Watkins, Dominic P. Petrella and Florence Sessoms
Posters
Environmental Impacts of Smart Irrigation and Mowing Height in Kentucky Bluegrass Lawns
By Daniel Sandor; co-authors Brian Horgan and Brian Davis
University Digital Conservancy link to poster
Precision Irrigation for Golf Courses Using Sensor and Mapping Technologies
By Chase Straw; co-authors Joshua Friell and Brian Horgan
University Digital Conservancy link to poster
Minnesota Regional Roadside Seed Bank Analysis
By Dominic Christensen; co-authors Joshua Friell, Jacob Jungers, Jon M. Trappe and Eric Watkins
University Digital Conservancy link to poster
Optimum Seeding Rate and Biomass Removal Timing for No-Mow Fine Fescue Golf Course Roughs
By Ryan Schwab; co-authors Eric Watkins, Andrew Hollman, Brian Horgan and Samuel Bauer
University Digital Conservancy link to poster
Developing Online Education and Training for Installation and Management of Roadside Turfgrasses
By Kristine Moncada; co-authors Jon M. Trappe, Samuel Bauer and Eric Watkins