Influence of Two Fertilizer Levels on Forage and Crude Protein Yields of Seven Tropical Grasses

Abstract

Two levels of a commercial fertilizer, analysis 15-5-10, (intermediate-2240 and high-4,480 kg/ha/year) were evaluated for green forage (GF), dry forage (DF), and crude protein (CP) yields and dry matter (DM) content of slenderstem digit (Digitaria pentzii), common Guinea (Panicum maximum), Makueni (Panicum maximum) Coastcross-1 Bermudagrass (Cynodon dactylon), Callie (Cynodon plectostachyus), Stargrass (Cynodon nlemfuensis var. nlemfuensis), and Carib (Eriochloa polystachya) grasses. Mean crude protein, phosphorus, potassium, calcium and magnesium contents at the intermediate and high levels, respectively, were 7.6, 8.7, 0.29, 0.25, 1.97, 2.02, 0.45, 0.49 and 0.23, 0.24. Grasses were cut 17 times at a 45-day interval for 765 consecutive days. Mean DF yield for the seven grasses increased 29% as a result of the higher fertilizer level. Significant differences in GF and CP yields occurred among grasses at the two fertilizer levels. At the intermediate fertilizer level, DF yields ranged from 22,364 to 34,717 kg/ha per year for Carib and Slender-stem digitgrass, respectively. At the high fertilizer level, the variation was from 31,188 to 43,126 kg/ha per year for Carib and Makueni grasses, respectively. During the short cool days from October 15, 1977 to February 27, 1978, Slenderstem digit and Makueni grasses significantly outyielded (P = .05) common Guinea, Star, and Carib grasses in total DF yields.