Source: NORTH CAROLINA STATE UNIV submitted to NRP
CULTIVAR DEVELOPMENT: ENHANCING SUSTAINABILITY IN THE SOUTHEASTERN UNITED STATES THROUGH COMMERCIALIZATION OF LOW-INPUT CENTIPEDEGRASSES
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
ACTIVE
Funding Source
AFRI COMPETITIVE GRANT
Reporting Frequency
Annual
Accession No.
1032285
Grant No.
2024-67013-42535
Cumulative Award Amt.
$450,500.00
Proposal No.
2023-11132
Multistate No.
(N/A)
Project Start Date
Jun 1, 2024
Project End Date
May 31, 2027
Grant Year
2024
Program Code
[A1143]- Conventional Plant Breeding for Cultivar Development
Recipient Organization
NORTH CAROLINA STATE UNIV
(N/A)
RALEIGH,NC 27695
Performing Department
(N/A)
Non Technical Summary
Turfgrasses have a significant impact on the U.S. economy, while also providing environmental benefits, enhancing aesthetics, and supporting human well-being. However, because of the significant input requirements of turfgrasses the turfgrass industry is facing sustainability challenges. To meet consumers' and environmental demands, North Carolina State University (NCSU), the University of Florida (UF), and the University of Georgia (UGA) have worked independently on improving centipedegrass, a highly desired low-input warm-season turfgrass species with minimal fertilizer and mowing requirements and relatively high resistance to both biotic and abiotic stresses. This proposal leverages the combined expertise of the three abovementioned land-grant universities to select, release, and disseminate new low-input centipedegrass cultivars with improved seed yield, stress resilience, and turfgrass quality that can be deployed at a regional level. Our primary goal is to screen advanced centipedegrass populations from NCSU, UF, and UGA across multiple Southeastern United States locations and pursue cultivar release and licensing for the top performing populations. Additionally, we will assess the yield stability of the parental lines for these populations, ensuring their commercial viability. We will leverage phenotypic and environmental data to provide an indication of the factors of the environment that are important for optimum turfgrass quality and adaptation in centipedegrass. Further, we will conduct on-farm trials with promising populations for increasing breeding stock in preparation for commercial release, and assess their performance under "real-world" conditions and promote "farmer-assisted participatory breeding". Our results will be disseminated through field days and other outreach and extension activities, which will facilitate adoption of these cultivars.
Animal Health Component
90%
Research Effort Categories
Basic
10%
Applied
90%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
20121991081100%
Knowledge Area
201 - Plant Genome, Genetics, and Genetic Mechanisms;

Subject Of Investigation
2199 - Ornamentals and turf, general/other;

Field Of Science
1081 - Breeding;
Goals / Objectives
The primary deliverable from this project will be the release of two centipedegrass cultivars: one adapted to the heat and humidity of the southeastern US, and one adapted to the upper boundaries of this region, including the transition zone, where winterkill is a concern. While these parent lines and advanced populations from the NC State University (NCSU), University of Florida (UF), and University of Georgia (UGA) breeding programs are well adapted to their respective states, nothing is known about their ability to perform - in terms of establishment rates, turfgrass quality, drought tolerance, winter survival, and sod quality- on a more regional basis. Therefore, the specific objectives of the proposed work are:Evaluation of advanced populations from the NCSU, UF, and UGA centipedegrass breeding programs in North Carolina, Georgia, and Florida to:Identify populations with superior performance for turf quality and stress toleranceCharacterize the climatic uniqueness of testing locationsContinue evaluation of parental lines at a larger scale at their respective breeding programs to increase breeding stock in preparation for commercial releaseEstablish on-farm trials for best populations to assess their performance under "real-world" conditions and promote "farmer-assisted participatory breeding"
Project Methods
Obj 1:In the first year supported by this proposal, 6-10 populations from NCSU, 6-10 from UGA-Tifton, one from UF, and four commercial cultivars ('TifBlair', 'Santee', 'Covington', and 'Common') will be sown in field trials at six locations in the Southeastern USA: Raleigh, Jackson Springs and Laurel Springs, North Carolina; Tifton and Griffin, Georgia; and Citra, Florida.All field trials will be established as randomized complete block designs with three replicates. Sowing of seed will be performed by hand in the late spring of 2024 at a rate of 0.115 kg per 93 m2 in 1.5m x 1.5m plots with 0.5m alleys in between. Evaluated traits will include: percent green cover, turf quality, turf quality under dorught, recovery from dorught, fall color, spring green-up, winterkill, and sod tensile strentght.Data will be analyzed using a mixed model approach implemented in ASReml-R (Gilmour, 1995; Butler et al., 2023) on a quarterly basis for breeders to be able to check the performance of their lines often. Environmental data will be collected and acquired from weather stations placed at research stations of the respective universities. In addition, soil information will be acquired from the Web Soil Survey (http://websoilsurvey.nrcs.usda.gov/) and previously conducted soil analyses. Phenotype and environmental data will be analyzed using a mixed model approach implemented in ASReml-R (Gilmour, 1995; Butler et al., 2023).Obj 2:In year 1, the parentals of the populations will be planted at the main research station of the respective breeding program. In late spring 2024, plugs of the parental lines will be randomized within a 2 m x 2 m block to ensure equal opportunity for pollination across all parental lines. In late fall, crossing blocks will be evaluated for inflorescence abundance which will be collected visually (1-9 scale, 1 = no inflorescences and 9 = 100% plot cover by inflorescences), and seed yield, which will be assessed after harvesting the inflorescences, drying them, separating seeds from dried biomass, and weighing the seeds. At NCSU and UF, germination tests will be conducted according to Bush et al. (2000).Germination rate and mean time of germination (MTG) will be assessed.Additionally at UGA, centipedegrass seed vigor will be evaluated using a thermal gradient following Grey et al. (2011). Inflorescence abundance, seed yield, germination rate, and MTG will be evaluated for two years in order to quantify the yield of the parental lines on a larger scale and confirm their commercial viability. In addition, activities under this objective will be fundamental to increasing seed stocks of the populations for on-farm and future trials.Obj 3:The preliminary data analysis of the data collected in the first two years supported by this proposal will be used to select the best populations to be planted in on-farm trials. The on-farm trials will be conducted in 1-2 sod farms per state in the year 3. We expect to evaluate the top 4-5 populations alongside commercial control 'Common', the most widely used centipedegrass cultivar. The populations included by each state might vary as NC locations might focus on the more cold-tolerant genotypes. In the spring of year 3, the seed will be sown at commercial rates in 3 m x 6 m strips in two replications depending on seed availability. Plots will be maintained (mowing, fertilization, irrigation, pesticide regimes) using the standard management practices for commercial production at each farm. Percent green cover will be collected monthly May through July through the use of UAS-based imaging to identify populations with higher germination and faster establishment rates. In the fall, commercial sod harvesting equipment will be used to collect sod pieces for quality evaluations. Sod quality evaluations will be performed according to Han (2009) and McCalla et al (2008) as described under objective 1A. Extension personnel at each institution will be engaged during this final stage in order to prepare extension materials highlighting the favorable characteristics of the new releases.

Progress 06/01/24 to 05/31/25

Outputs
Target Audience:Students and research staff were engaged directly through participation in the research project, receiving training in turfgrass science, field management practices, and experimental design. This hands-on involvement provided valuable learning opportunities and contributed to the development of technical and analytical skills relevant to careers in turfgrass research and industry. In addition, growers and turfgrass industry professionals were reached through participation in a field day and plot tours where project trials were showcased. These events served as a platform for science-based outreach, allowing stakeholders to observe experimental plots, interact with researchers, receive updates on cultivar performance, and discuss about the seeded turfgrass market. This direct engagement helped ensure that preliminary findings from the research were shared with relevant end-users who could benefit from them. Changes/Problems:Trials in Laurel Springs and Sandhills were affected by Hurricane Helene, which hit North Carolina on 27 Septemeber 2024 causing significant damage. At Sandills, strong winds ripped the germination cloth and lots of seed wash off, which resulted in very poor establishment. At Laurel Springs in the NC mountains where devastating floods occurred, the trial was flooded for a week resulting in complete loss.These trials will need to be re-sown in 2025. What opportunities for training and professional development has the project provided?Students (three graduate and three undergraduate) and research staff were engaged directly through participation in the research project, receiving training in turfgrass science, field management practices, and experimental design. This hands-on involvement provided valuable learning opportunities and contributed to the development of technical and analytical skills relevant to careers in turfgrass research and industry. How have the results been disseminated to communities of interest?• Field days: • 2024 NC State turf field day, Raleigh, NC. Aug. 14 (800 attendees) • Plot tours • Four plot tours occurred in spring 2025 at Citra, FL (8 individuals) • Two plot tours occurred in spring 2025 at Raleigh and Sandhills, NC (5 individuals). What do you plan to do during the next reporting period to accomplish the goals?I. Evaluation of advanced populations from the NCSU, UF, and UGA centipedegrass breeding programs in North Carolina, Georgia, and Florida to: 1. Identify populations with superior performance for turf quality and stress tolerance • Re-sowing the trial in Laurel Spring, NC. • Data collection of multiple traits across five locations. • Preliminary data analysis to support the future selection of superior populations for the on-farm trials. 2. Characterize the climatic uniqueness of testing locations • Data collection on several traits from the trials in Obj. 1 A to achieve this goal. II. Continue evaluation of parental lines at a larger scale at their respective breeding programs to increase breeding stock in preparation for commercial release • Planting of parent trial at Raleigh, and initiation of seed yield data collection. • Continue the parental evaluation in Tifton, GA. III. Establish on-farm trials for best populations to assess their performance under "real-world" conditions and promote "farmer-assisted participatory breeding" • Continue data collection to support the future selection of top populations for the on-farm trial establishment.

Impacts
What was accomplished under these goals? I. Evaluation of advanced populations from the NCSU, UF, and UGA centipedegrass breeding programs in North Carolina, Georgia, and Florida to: 1. Identify populations with superior performance for turfgrass quality and stress tolerance Seeds were exchanged among partner universities and trials were sown in the summer of 2024 at five locations: Laurel Springs, NC; Jackson Springs, NC; Raleigh, NC; Tifton, GA, and Citra, FL. • Jackson Springs, NC: The trial was sown on 8/21/2024 and covered with white fabric to prevent seed spread caused by irrigation or rainfall. Unfortunately, a storm on 08/29/2024 destroyed the fabric. The trial was re-covered the following day; however, germination was poor. A new trial was sown again on 05/09/2025. • Raleigh, NC: The trial showed good germination, and despite the late sowing date (08/13/2024), the plots survived the winter. They are currently in the establishment phase. Data collection on establishment, using sUAS, was collected in the fall of 2024 and in the spring 2025. Images are being processed. • Laurel Springs, NC: The trial was sown and covered with white fabric on 08/20/2024. In late September, Tropical Storm Helene swept through the southeastern United States, causing widespread flooding in North Carolina. The centipedegrass trial was washed out by the flood. A new trial will therefore be sown in June of 2025. • Tifton, GA: The trial was sown on 8/27/2024 by broadcasting the seeds on 5' x 5' plots using a custom-designed seed chamber and raking the plots to cover the seeds. The trial was irrigated once a day for a week and continued to be irrigated as needed. The plots have been fully established, and we continue to collect percent green cover and vegetative indices, using sUAS. Data was collected in the Fall of 2024 and in the Spring of 2025. • Citra, FL: The trial was sown 10-15-24. Germination was low, but adequate. Data collection began in the spring of 2025. 2. Characterize the climatic uniqueness of testing locations • Trials from the Objective 1A were established, and data collection has begun to support this objective. II. Continue evaluation of parental lines at a larger scale at their respective breeding programs to increase breeding stock in preparation for commercial release • Raleigh, NC: Parental lines were increased in the greenhouse, and it will be planted in June of 2025. • Tifton, GA: Parental accessions (20 lines) of a broad-base synthetic population (TC1952), one of the most advanced populations, is maintained at the UGA Tifton Camus. We continue to evaluate the parents for the increase in breeding stock. Nine other populations are maintained as bulk synthetics at Tifton, GA. The parental lines and bulk synthetics will be evaluated through the end of the project period for inflorescence abundance, seed yield, and rate of germination. III. Establish on-farm trials for best populations to assess their performance under "real-world" conditions and promote "farmer-assisted participatory breeding" • Trials from the Objective 1A were established, and data collection has begun to support in the future selection of top populations for on-farm trials.

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