Effect of Organic and Inorganic Fertilizers on Growth and Yield of Tef (Eragrostis tef) in the Central Highlands of Ethiopia

A field experiment was conducted for two consecutive cropping seasons (2013-2014) on farmers’ fields in Dendi district of Oromiya Regional State. The objective of this study was to evaluate the effect of organic and inorganic fertilizers on growth and yield of tef and soil chemical properties. The treatments included eleven selected combinations of organic and inorganic nutrient sources (Farm yard manure, vermicompost, Compost, Nitrogen and Phosphorus). The design was randomized complete block with three replications. Results showed that tef yield, some yield components and soil chemical properties are significantly affected by the application of organic and inorganic fertilizer sources. The highest tef grain yield (3144.8kg ha-1) and biomass yield (12562.5kg ha-1) were obtained from the applications of half doses of vermicompost (4.8t ha-1) which is based on recommended N equivalent and half doses of the recommended nitrogen and phosphorus fertilizers (34.5kg ha-1N and 30kg ha-1P that half dose contains) followed by 2846 kg ha-1and 11833.3 kg ha-1for grain yield and biomass yield, respectively, due to the application of the full recommended N and Prates (69kgN ha-1and 60kg P ha-1). Application of the different organic fertilizers improves the organic matter, Total N, available P and pH of the soil in the study area. The result also showed that the highest marginal rate of return was obtained from application of 3.2t ha-1vermicompost + 2.37t ha-1 conventional compost + 1.37t ha-1 farmyard manure (based on equivalent N rate, which is economically the most feasible alternative on vertisols of central Ethiopian highlands.

本研究于2013-2014年连续两个种植季，在奥罗米亚州（Oromiya Regional State）登迪区的农户田块开展田间试验。本试验旨在评估有机与无机肥料对苔麸（tef）生长、产量及土壤化学性质的影响。试验设置11种筛选出的有机与无机养分源组合处理，涵盖农家肥（Farm yard manure）、蚯蚓粪（vermicompost）、堆肥（Compost）、氮肥与磷肥。试验采用随机完全区组设计，设置3次重复。结果表明，有机与无机肥料配施可显著影响苔麸产量、部分产量构成因子及土壤化学性质。其中，以推荐氮素当量为基准的半量蚯蚓粪（4.8吨/公顷）配合半量推荐施用量的氮、磷肥（即分别施用34.5kg/ha氮与30kg/ha磷），可获得最高的苔麸籽粒产量（3144.8kg/ha）与生物量产量（12562.5kg/ha）；其次为全量推荐氮磷肥配施（69kgN/ha与60kgP/ha），其籽粒产量与生物量产量分别为2846kg/ha与11833.3kg/ha。施用不同类型有机肥料可提升研究区域土壤有机质、全氮、有效磷含量及pH值。研究同时显示，施用3.2吨/公顷蚯蚓粪+2.37吨/公顷常规堆肥+1.37吨/公顷农家肥（基于等效氮素施用量）可获得最高边际收益率，该方案在埃塞俄比亚中部高地的变性土（vertisols）上具备经济可行性。