The Status of the Joint Bahiagrass Breeding Program between the University of Florida (U.S.A.) and the National University of the Northeast (Argentina)

FLORENCIA MARCÓN; ANN R. BLOUNT; CARLOS A. ACUÑA; MARIO H. URBANI; ERIC J. MARTÍNEZ; CAMILO L. QUARIN; KENNETH H. QUESENBERRY

Knoxville, TN

Congreso; Southern Pastures and Forage Crop Improvement Conference; 2017

Southern Pastures and Forage Crop Improvement Group

Bahiagrass (Paspalum notatum Flüggé) is a warm-season perennial grass used for forage and turf in the subtropics. We have developed a joint bahiagrass breeding program between the University of Florida, United States, and the National University of the Northeast, Argentina through an international cooperation agreement. The program is two-fold; first we evaluate and select apomictic ecotypes Paspalum species, particularly P. notatum (bahiagrass) and close relatives and secondly, we create and evaluate apomictic hybrids. The main traits of interest in this collaboration include forage yield, frost tolerance, winter growth ability, nutritive value, seed production, seed retention and germination. The selection of ecotypes is based on the successful evaluation of individual apomictic genotypes and seed or plants will be conserved by both Universities. The creation of apomictic hybrids is carried out through crosses that we have made between sexual tetraploid genotypes and apomictic tetraploid genotypes. The obtained hybrids are then sorted by their mode of reproduction (apomictic, facultative apomictic or sexual). The highly apomictic hybrids and ecotypes that exhibit forage or turf potential are selected and evaluated in the field. This effort produces apomictic forage-types that can be introduced in subtropical beef-cattle production systems. An example of this is the release of the cultivar Boyero UNNE (Reg. No. CV- 5, PI 676021) bahiagrass that was obtained by hybridization and was evaluated in different locations of Argentina and Florida. This cultivar had superior seasonal growth in comparison to the most popular tetraploid cultivars. At present, we are developing a new hybrid improvement technique based on a sexual, synthetic tetraploid population (SSTP) previously generated by researchers of Argentina. The development of this new synthetic sexual population will allow improving the tetraploid germplasm of P. notatum through recurrent selection based on combining ability. The objective of this technique is to exploit the heterosis of the obtained hybrids by crossing sexual genotypes selected from SSTP with apomictic genotypes based on additive and non-additive genetic effects. Ultimately, our goal is improving the forage characteristics of Paspalum species, focusing initially on bahiagrass.