Heritability estimates for turfgrass performance and stress response in zoysia spp.
Zoysiagrasses (Zoysia spp.) are widely adapted and highly variable; however, information is lacking regarding the heritability and potential for improvement of numerous performance characteristics. Three individual replicated field studies, which included 90 very fine, 108 fine, and 126 coarse-textured zoysiagrass genotypes, respectively, were conducted near Gainesville, FL, to determine the response and broad-sense heritabilities of 10 turfgrass performance and stress-related characteristics. Genotypic variance largely contributed to the wide range in expressed phenotypic response for plot coverage, turf density, turf quality, genetic color, and seedhead density, which resulted in higher broad-sense heritability estimates (0.62 H2 0.94). Fall dormancy and spring greenup were influenced more by the environment and had lower heritabilities (0.32 H2 0.58). Turf quality was also rated considering the effects of glufosinate [2-amino-4-(hydroxymethylphosphinyl)butanoic acid] herbicide application, Bipolaris incidence, and mole cricket (Scapteriscus spp.) damage. Large error variances and low broad-sense heritablities were typical for these stress-related traits. Potential exists for improvement of characteristics that exhibited large amounts of genetic variation and were less influenced by the environment. Broad-sense heritability estimates indicate the possibility of combining desirable traits in superior clonally propagated F1 hybrids.