AGRONOMIC CHARACTERISTICS, FORAGE YIELD AND CHEMICAL COMPOSITION OF Urochloa GRASS CULTIVARS UNDER MIDLAND CLIMATIC CONDITIONS OF SOUTHERN ETHIOPIA

Abstract

Background. Different forage innovations have been used to alleviate livestock feed shortage in Ethiopia. Napier, Rhodes, and Desho grasses are the most widely cultivated forage grasses in the backyard system. Objective. To evaluate the effect of harvesting age of Urochloa grass cultivar/ accessions on morphology, forage yield, chemical composition at Wolaita Sodo State dairy farm, Ethiopia. Methodology. The experiment involved a 5 × 3 factorial arrangement in a Randomized Complete Block Design with three replications, three harvesting ages (60, 90, and 120 days of age), and five Urochloa grass cultivars/ accessions (Urochloa hybrid 'Mulato II', Urochloa mutica (Forssk.) T.Q. Nguyen, Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster 'acce. no. DZF13151', Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster 'Piata' and Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster 'acce no. DZF16550') during 2020˗2021. Results. Plant height and number of leaves were greater (P<0.05) for U. mutica than for the remaining cultivars across the three harvesting ages. The tillers number was greater (P<0.05) for U. brizantha acce. no. 16550 at120 days of harvesting than the remaining cultivars and harvesting ages over the two years. The greatest leaf length was for Piata at 120 days of harvesting compared to the other cultivars and harvesting ages. The leaf: stem ratio was also the highest (P<0.05) for Piata at early age of harvesting. The dry matter, crude protein and digestible organic matter yields varied significantly among cultivars with the highest (P<0.05) values obtained for U. mutica across the three harvesting ages. The highest (P<0.05) crude protein (CP), in vitro organic matter digestibility (IVOMD) and metabolizable energy concentrations were observed for Mulato II and the lowest (P<0.05) value was recorded in U. brizantha acce. no. 13151 across the three harvesting ages. Most morphological characteristics and yield parameters increased (P<0.05) with increasing harvesting age. However, the CP, IVOMD, and leaf: stem decreased with increasing harvesting ages. Implications. The higher DM yield and forage quality of U. mutica and Mulato II may be an indicator of adaptation to midland climatic condition. Conclusion. Growing the outperforming cultivars, Mulato II and U. mutica, and harvesting at 90 days of age is considered as a suitable practice to improve fodder production and availability in the midland agroecology of Ethiopia.

Keywords

• harvesting age
• dry matter yield
• correlation
• crude protein
• chemical composition.