Yield and Nutritive Value of Sorghum, Maize and Soybean Forages Harvested in Southwestern Puerto Rico

Abstract

Six varieties of forage sorghum (Sorghum bicolor) and sorghum X sudangrass hybrids (S. bicolor X S. sudanese), six varieties of grain sorghum (S. bicolor) and three varieties each of maize (Zea mays) and soybean (Glycine max) were grown in 1.2 x 3.7 m plots at the Lajas Experiment Substation. All plots were harvested in the boot, flower and dough stages. Ratoons of the sorghum varieties were also harvested after 45 days of regrowth until the stands diminished. The forage sorghums and maize had higher yields of green and dry material than the grain sorghums. However, only the grain sorghums showed any significant increase in yield as the crop matured. All crops decreased in nutritive value with advance in age. In general, maize was higher in nutritive value than the forage sorghums. Results indicated that forage sorghums can be recommended due to high yields of good quality forage on irrigated lands on the south coast. However, results with soybean forage were poor. It does not appear feasible to produce soybeans to enhance the crude protein content of forage pellets.