Performance of Buffelgrass Germplasm with Improved Winter Survival

Lack of winter hardiness in buffelgrass [ Cenchrus ciliaris L.; syn. Pennisetum ciliare (L.) Link] currently limits the utilization of this species in Texas and northern Mexico. This study was conducted to assess differences in field survival and yield potential of buffelgrass germplasm believed to have increased levels of winter hardiness. To document differences in field winter survival seedlings of five buffelgrass genotypes (‘Common’, ‘Llano’, ‘Nueces’, PI 409704, and T‐7040) were established at six locations in Texas ranging from 28 to 34°N latitude. The winter‐hardy species Pennisetum orientale L. cv. Cowboy was included as a check. The buffelgrass entries PI 409704 and T‐7040 (a 2 n + n hybrid between 409704 and an unknown male parent) had greater field survival than the cultivars Common, Llano, and Nueces, but were less winter hardy than Cowboy at the three locations (Knox City, Stephenville, and Vernon) north of College Station. All entries survived the winter at Beeville, College Station, and Uvalde. Yield at two cutting heights was evaluated over a 3‐yr period at College Station. The rhizomatous cultivars Llano and Nueces had the greatest yield when harvested at 50 mm, while no significant differences existed among Llano, Nueces, PI 409704, and T‐7040 when harvested at 150 mm. Defoliation height influenced winter survival of Common buffelgrass at College Station. During the winter of 1987–1988, 60 and 20% of the Common plants failed to survive at the 50‐ and 150‐mm defoliation heights, respectively. Defoliation height did not affect crown nonstructural carbohydrate concentration (CHO). The most winter‐hardy entry, Cowboy, had the highest CHO; the least winter‐hardy entry, Common, had the lowest. These results suggest that winter‐hardy pentaploid buffelgrass germplasm such as PI 409704 have the potential to expand the current range of buffelgrass.