Effects of Seeding Rate and Sowing Date on Herbage Dry Matter and Seed Yield Performance of Brachiaria Grass Grown under Subhumid Climatic Conditions of Western Oromia, Ethiopia

摘要

The experiment was conducted at Bako Agricultural Research Center (BARC) for three years (2013, 2014 and 2015) to compare the effect of sowing dates and seeding rates on productivity of Brachiaria decumbens. The treatments consisted of four sowing dates (1 week, 3 weeks, 5 weeks and 7 weeks) after onset of main rain and four levels of seeding rates (6, 8, 10 and 12) kg ha -1 . Accordingly, sowing dates started on May 28, 2013 and thereafter at 14-days intervals: June 11, 2013; June 25, 2013 and July 09, 2013. An experimental design of a randomized complete block in factorial arrangement with three replications was used. The analysis of variance indicated that seeding rate by planting time interaction effect was highly significant (p0.01) for herbage DM yield and seed yield. However, none significant differences were observed for plant height, plot cover and vigorousity. The highest herbage dry matter yield and seed yield (18.67 ton ha -1 ) and (6.37 Qt ha -1 ), respectively were obtained from seeding rate of 6 kg ha -1 that planted at three weeks after the commencement of main rainy season. Year have also significant (p0.01) effect on both herbage dry matter and seed yields. Maximum herbage dry matter yield (22 ton ha -1 ) and seed yield (9.76 qt ha -1 ) were obtained during the first year (2013) in the second sowing time (June 11, 2013) at 6 kg ha -1 seeding rate. Therefore, it can be recommended that the lower seed rate (6kg ha -1 ) sown at 3 weeks after commencement of the main rain was produced better herbage DM (18.7 ton ha -1 ) and seed yields (6.37 qt ha -1 ) and was favorable for Bako area and similar agro ecologies.