Bahiagrass Tetraploid Germplasm: Reproductive and Agronomic Characterization of Segregating Progeny

The tetraploid germplasm of bahiagrass, Paspalum notatum Flugge, is an unexploited source of variability that can be used for the genetic improvement of this species as forage or turf. The objectives of this research were to develop a segregating population by hybridizing induced sexual and apomictic clones and to characterize the resulting population for mode of reproduction, seed fertility, growth habit, seasonal growth pattern, and frost resistance. A population of 591 hybrids had a 4:1 ratio between sexual and apomictic (facultative + obligate apomictic) plants and an 8:1 ratio between others (facultative apomictic + sexual) and obligate apomictic plants. The general fertility of the progeny was higher than that of the induced sexual parents. Significant differences were observed for self- and cross-fertility among apomictic progeny and for self-fertility among sexual progeny. Most sexual progeny set the same amount of seed when self- or cross- pollinated, indicating an absence of self-incompatibility. Marked variation was observed for growth habit, seasonal growth patterns, and frost resistance among the progeny. Heritability estimates obtained for these characteristics indicate that selection can be successfully used for the genetic improvement of this species.