EFFECT OF NITROGEN FERTILIZER AND HARVESTING DAYS ON YIELD AND QUALITY OF RHODES GRASS (Chloris gayana) UNDER IRRIGATION AT GEWANE, NORTH-EASTERN, ETHIOPIA

The experiment was undertaken to assess Rhodes grass yield and nutritional quality at different harvesting days and levels of N fertilizer application grown under irrigation at Gewane, Afar region. The field experiment was arranged in a 3 x 4 factorial randomized complete block design with three replications. The treatments were three levels of harvesting days (60, 90 and 120 days) and four level of N fertilizer application (0, 23, 46 and 69 kg ha-1 ). Plant height (PHT), number of tillers per plant (NT), number of leaves per plant (NLP), length of leaves per plant (LLP), leaf to stem ratio (LSR), number of internodes per plant (NIP), length of internodes per plant (LIP), number of internodes per tiller (NIT), DMY and CPY significantly (P < 0.01) increased as the level of N fertilization and days of harvesting increases. However, except for the length of internodes per plant (LIP), interaction effect is not significant for all the parameters listed above. The highest mean dry matter yield (DMY) recorded was 17.58 and 16.54 ton ha-1at 120 days of harvesting and 69 kg ha-1N fertilizer rates, respectively. The crude protein content (CP), calcium (Ca), phosphorus (P), and total ash content significantly (P < 0.01) increased as the level of N fertilization increases but declined as days of harvesting increases; however, except for the crude protein(CP) interaction effect is not significant. The dry matter content (DMP), neutral detergent fiber (NDF), acid detergent fiber (ADF),acid detergent lignin ( ADL), in vitro dry matter digestibility (IVDMD) were significantly different (P