EFFECT OF NITROGEN-FERTILIZATION ON SPECIES OF THE CYNODON GENUS IN ATYPICAL RED FERRALLITIC SOIL .1. YIELD COMPONENTS

The performance of species and varieties of the Cynodon genus (C. dact ylon, cv. Coast, C. dactylon cv. Cross 1, C. dactylon cv, Cross 2, C. nlemfuensis, cv, Panamanian and C. nlemfuensis vc. Jamaican) were stud ied on applying 0, 200 and 400 kg/ha/year of nitrogen in a typical red ferrallitic soil. A 3 x 5 factorial arrangement was used in a random block design with 4 replicates. Pasture height varied P < 0.001) with the nitrogen dosage and differed between species. The cv. C. nlemfuens is and C. dactylon cv. Cross 1 reached the greatest heights (42,39 and 37 cm) and nitrogen increased the height of these pastures (30.5, 34. 6 and 39.9 cm with 0, 200 nd 400 kg N/ha, respectively). The cv. C. nl emfuensis had highest DM content (P < 0.001) during the second year. T he nitrogen decreased (P < 0.001) the DM percentage and the highest va lues were present in the dry period. There was a nitrogen x species in teraction for the percentage of leaves. The varieties of C. dactylon s howed the highest leaf percentages with 40 and 75%. There were differe nces (P < 0.001) in yield with N dosage, the highest increments were a chieved in the rainy period and yield percentages for the dry period v aried between 20 and 40%. Sward density showed a N x species interacti on with the increment of this indicator with N dosage in C. nlemfuensi s cv. Panamanian and C. dactylon cv. Cross 1 which presented higher de nsities with 86 and 76 kg DM/ha/cm for the dry period. The highest pas ture purity with the dosage of 400 kg/ha of N were evident with the cv . of C. nlemfuensis (P < 0.001) with 71 and 72%. It is concluded that the cv. of C. nlemfuensis had better performance and botanical composi tion than C. dactylon and show higher values in yield components with 400 kg N/ha.