Genetic Variability and Relationships for Adaptive, Morphological, and Biomass Traits in Chinese Bermudagrass Accessions

Abstract

Bermudagrass, Cynodon dactylon (L.) Pers., is geographically widely distributed and represents the most important taxon in the genus in terms of its extensive uses for turf, forage, soil stabilization, and remediation. This warm‐season, sod‐forming grass is indigenous to China, but limited information is available for adaptive, morphological, and biomass traits in the Chinese germplasm. Accordingly, objectives of this study were to quantify genetic variability for 24 morphological, adaptive, and biomass‐related traits and to characterize relationships among traits of 114 Chinese clonal accessions in a field experiment at Stillwater, OK. ‘Tifsport’, ‘Tifway’, ‘Midland’, and ‘Tifton 44’ bermudagrass cultivars were used as controls in the field experiment. Differences among the accessions were significant (P < 0.01 or P < 0.05) and of large magnitude for all response traits. When grouped by ploidy level, variation among accessions was far greater in tetraploids (104) than in pentaploids (3) and hexaploids (7). Response traits of plant height, leaf blade length and width, and internode length and diameter were significantly and positively correlated with each other to various degrees. Biomass yield was significantly associated with the traits of spring greenup, plant height, winter kill rate, internode, and sod density. Winter kill was positively correlated with weed prolificacy, but negatively with spring greenup. Multiple regression and path coefficient analyses indicated plant height, winter kill, greenup, sod density, and internode size to be predictive of forage yield. The large amount of genetic variability among the Chinese accessions should be a valuable resource for the development of improved turf and forage cultivars.