Multispecies genotype × environment interaction for turfgrass quality in five turfgrass breeding programs in the southeastern United States

Abstract

In breeding programs, superior parental genotypes are used in crosses to generate novel genetic variability for new selection cycles. Genotypes are usually more adapted to environments where the breeding program is located, since selections are performed under specific agroecosystems. Thus, the objective of this study was to evaluate the performance of bermudagrass (Cynodon Rich. species), St. Augustinegrass [Stenotaphrum secundatum (Walter) Kuntze], seashore paspalum (Paspalum vaginatum Sw.), and zoysiagrass (Zoysia Willd. species) breeding lines from five different breeding programs (North Carolina State University, Oklahoma State University, Texas A&M University System, University of Florida, and University of Georgia) across the southeastern United States. Three breeding nurseries for each species were evaluated for 2 yr at eight locations: Citra and Hague, FL; College Station and Dallas, TX; Griffin and Tifton, GA; Stillwater, OK; and Jackson Springs, NC. Turfgrass quality (TQ) was evaluated (rated on a 1–9 scale) across repeated measurements over time. Data were analyzed using mixed models, and principal component analyses were performed using predicted genotypic values. The narrowest range in variation for TQ performance was observed in seashore paspalum breeding lines, whereas greater variation was observed for St. Augustinegrass and zoysiagrasses. St. Augustinegrass presented the lowest genotype × environment interaction in all nurseries. Specific adaptability was not observed for the lines developed by different breeding programs, with the exception of the bermudagrass lines from Oklahoma State University in Nursery 3.

Using base index for selection of St. Augustinegrass breeding lines evaluated in multienvironment trials for turfgrass quality traits and stress tolerance in North Carolina

“…The GEI poses a challenge as plant breeders must either select for genotypes that perform well across environments, sacrificing potential genetic gain, or develop separate populations for each environment where performance is significantly different (Kang, 1997). While some studies have found GEI to influence St. Augustinegrass performance (Reynolds et al., 2009), others found that environment plays a minor role in genotype variability (Kimball et al., 2016; Pereira et al., 2021) and indicated the species has better stability across locations than other warm‐season turfgrass species (Gouveia et al., 2021). In this study, St. Augustinegrass performance was stable across locations as entry × location was an insignificant factor for all traits with the exception of EST.…”

“…While studies have been conducted on evaluating several St. Augustinegrass traits of agronomic and economic importance including overall TQ (Gouveia et al., 2021; Kimball et al., 2018; Philley et al., 1996; Reynolds et al., 2009), genetic color, leaf texture (Kimball et al., 2016), winter survival (Kimball et al., 2018; Milla‐Lewis et al., 2013b; Moseley et al., 2021; Philley et al., 1996; Reynolds et al., 2009), and gray leaf spot resistance (Carbajal et al., 2021), little is yet known about the relationship among these traits or the best selection scheme for improving them. As the market demand for St. Augustinegrass continues to grow in North Carolina, there is a need for cultivars that combine superior TQ with tolerance to local biotic and abiotic stresses.…”

Multilocational screening identifies new drought‐tolerant, warm‐season turfgrasses

“…Gouveia et al. (2020) reported that seashore paspalum experimental genotypes had the narrowest range in variation for visual turf quality when compared with other warm‐season species in multilocation drought trials. Our data indicate that even this narrower range of variation among seashore paspalum genotypes should be adequate to expect improvements in drought tolerance using this multilocational screening approach for selection of drought‐tolerant genotypes.…”

“…This requires multiyear and multilocation testing to ensure stable performance. A recent federal grant emphasizing the development of drought‐tolerant, warm‐season cultivars provided an opportunity for southern turfgrass breeders to evaluate a large set of diverse germplasm for drought tolerance at multiple locations across the southern United States (Gouveia et al., 2020). One of the primary goals of this collaborative effort was to rapidly and efficiently identify broadly adapted genotypes with superior drought tolerance.…”

Breeding for drought tolerance in perennial ryegrass (Lolium perenne L.) and tall fescue (Lolium arundinaceum [Schreb.] Darbysh.) by exploring genotype by environment by management interactions

“…Therefore, advanced statistical methods are key to predict the genetic value of breeding lines as accurately as possible (Smith & Spangenberg, 2014). These statistical methods need to take into account the spatial variation and correlation within a trial, as well as the temporal correlation between repeated measures, to improve the accuracy in the selection process (Faveri et al, 2015; Gouveia et al, 2021). These methods can be even more relevant when it is intended to select genotypes under stress conditions, because the discrimination of tolerant/susceptible genotypes tends to be more difficult due to low heritability estimates and higher environmental variance (Hoffmann & Merilä, 1999).…”