Forage Yield, Quality And Persistence Of Interspecific Pennisetum Hybrids In The Caribbean

The species Pennisetum purpureum includes perennial, high yielding and good quality forage types. However, the need for vegetative propagation has limited its commercial use. In two 2-year experiments, forage yield and quality, and stand persistence of 'Mott' dwarf elephantgrass (P. purpureum) were compared with either those of other pure lines of elephantgrass (N43, N114, N127 and N128) or their interspecific hybrids with pearlmillet (P. glaucum) grown in mixture with glycine (Neonotonia wightii). Grasses were harvested every 60 to 100 days, based on rainfall. In neither year was there a genotype x harvest date interaction for dry matter yield. Annual forage yield of tall pure lines or their triploid hybrid with pearl millet was 21-29 t/ha compared with 9-23 t/ha from Mott and its seeded hexaploid derivatives. Forage in vitro organic matter digestion (IVOMD) for Mott (65%) at 60-day regrowth was similar to the hexaploids, but superior to the tall lines (60%). Minimum crude protein (CP) content and IVOMD of Pennisetum forage stockpiled for 90 days were 7% and 54% for dwarf types and 6% and 54%,for tall types, respectively. Mott cultivar maintained higher plant and tiller numbers than the hybrids. Legume content of dry forage at the final harvest was 40-48% for the hybrids and 28% for Mott. Seed propagated Pennisetum hybrids have a potential for stockpiled forage in the Caribbean if their persistence is improved.