The study was conducted at Mechara Agricultural Research Centre during 2016-2018 to evaluate nutrient content of vermicompost made from different substrates. The treatments were sorghum straw, maize straw, teff straw, haricot bean straw, grass straw and mixture of all straws. A red worm (Eisenia fetida) was selected to digest the substrates. The substrates was chopped and added to the worm bin volume calculated using spherical frustum formula 1/6πh (3a 2 +3b 2 +h 2 in a ration 2.5:1 ration of cattle manure to crop residue in weight basis. Water was sprayed to maintain optimum moisture for worms as it needed. The vermi composting process was started by releasing 100 worms in to the substrates. Matured composite vermicompost samples were prepared and collected for laboratory analysis. The laboratory result showed that, the pH and EC values of all type of vermicompost are found in suitable range for survival of earthworms and also for plant growth. Data with regards to %OC, C: N ratio and CEC of vermicompost made from all material is excellent and promise for improvement of soil properties. Relatively the highest (4.26%) and lowest (3.04%) TN content was recorded from vermicompost made from grasses and haricot bean substrates respectively. The highest value of available P and K was also registered from vermicompost prepared from all materials. Even if the values of recorded exchangeable Ca, Mg, K and extractable micro nutrients were different, the vermicompost obtained from all substrates were rich in exchangeable cations and micro nutrients. Therefore, the nutrient content of vermicompost prepared from all substrates showed the highest values for all macro and micro plant nutrients. Thus, the vermicompost made from all materials could correct the plant nutrient imbalance and could be used for vermicompost preparation based on the accessibility of materials. Also utilizing the vermicompost for crop production and enhancing soil fertility.

The study was conducted for three consecutive years (2011/2012 to 2013/2014) to evaluate the growth and production of banana (Robusta variety) with different water harvesting structure in Daro Labu districts of Oda Leku peasant association. The water harvesting structures used as treatments were semi-circular bund with and without mulch, negarim micro catchment with and without mulch and normal pit with and without mulch (control). The treatments were laid out in randomized complete block design on three farms as a replication. The data on yield, number of fingers, survival rate/6 month, number of sucker/2 years, plant height, and area coverage/1 year and 9 months were collected. The statistical analysis revealed that there was no significant difference (p>0.05) among treatments on survival rate, number of sucker, plant height, and area coverage but there was a highly significant variation (p<0.01) among treatments on yield and number of fingers. The means of plant height, area coverage and number of sucker on semicircular bund with mulch and negarim micro catchment with mulch were better than the structures without mulch and control. Both structures are therefore recommended with mulch for banana production in moisture stress areas and similar agro-ecologies.

Farmers are using NPS fertilizer rates in the area without any recommendation of crop response to the respective fertilizers This experiment was conducted to evaluate the effect of NPS fertilizer rate for higher yield of bread wheat in Wachale district. The experiment consisted six rates of NPS fertilizer rate supplemented with 92 kg N ha -1 laid out in RCBD with three replications. Improved variety of bread wheat Danda'a was used. The analyzed result indicated that, plant height and wheat grain yield were significantly (P<0.05) influenced by NPS fertilizer rate. The highest (94.56 cm) plant height was recorded from the application of 100% P-critical in NPS fertilizer rate and the lowest (63.62 cm) plant height was recorded from unfertilized plot. The highest (2833 kg ha -1 ) grain yield was obtained from the application of 100% P-critical in NPS fertilizer rate and the lowest (888 kg ha -1 ) grain yield was obtained from unfertilized plot. Partial budget analysis showed that the highest net benefit (53401.51 ETB ha -1 ) and marginal rate of return (MRR) (1093.80%) were obtained from the fertilizer application of 100% P critical in NPS fertilizer). Therefore, 100% equivalent rate of NPS fertilizer rate in relative to determined critical phosphorus supplemented with 92 kg N ha -1 for bread wheat could be recommended and thus soil test based crop response phosphorus fertilizer recommendation with 92 kg ha -1 of Nitrogen could be demonstrated and further scaled up for Bread wheat in Wachale district.

Appropriate soil fertility management practices based on the actual limiting nutrients and crop nutrient requirement for a given crop is economic and judicious use of fertilizers for sustainable crop production. Moreover, application of balanced fertilizers and nutrient requirements of the crop is the basis to produce more crop yield from the land under cultivation. Accordingly, field experiment was conducted in 2019 & 2020 main cropping season to determine NPS fertilizer rate in relative to determined P-critical and P-requirement factor for tef and to estimate the economically feasible NPS fertilizer rate for higher yield of tef in Girar Jarso district. The indicate that, plant height, spike length, straw and grain yield was highly significantly (P<0.01) affected by NPS fertilizer rate. The highest plant height (86.32cm), spike length (32.51cm), straw yield (7004 kg ha -1 ) and grain yield (1622 kg ha -1 ) of tef was recorded from the application of 100% P-critical from NPS fertilizer rate supplemented with recommended Nitrogen whereas, the lowest value was recorded from the field without fertilizer which was significantly inferior to all other treatments. Furthermore, the economic analysis depicted that, application of NPS fertilizer at the rate of 100% P-critical in NPS fertilizer with recommended Nitrogen fertilizer (92 kg N ha -1 ) for the production of tef was more economically beneficial for the district. In conclusion, farmers could be advised to use 100% PC from NPS fertilizer rate with recommended nitrogen for tef production in the district.

The field experiment was conducted to verify the determined optimum amount of nitrogen (92 kg N ha -1), critical P concentration (15 ppm) and P requirement factor (6.1) for tef production in Debre Libanos Districts. The experimental field was arranged with 3 treatments. The trial was carried out in Randomized Complete Block Design (RCBD) with seven replications over different Farmers field . Control (without fertilizer), Blanket recommendation (100kg Urea and100kg DAP) and soil test based fertilizer recommendation with recommended Nitrogen 92 kg ha -1 were used as a treatment. The gross plot area was 10 * 10m and the space between plots was 0.7m. The required amount of seeds was weighed per plot by considering the recommended rate of tef seed per hectare. The result from this study indicate that an optimum rate of nitrogen (92 Kg N/ha) and soil test based phosphorus fertilizer recommendation was highly significantly influence plant height, panicle length, biomass and grain yield of tef. The highest plant height (82 cm) panicle (27.78 cm), biomass yield (4673kg ha -1) and grain yield (1588 kg ha -1) was recorded from the application of soil test based fertilizer recommendation in conjunction with recommended optimum Nitrogen. The results of the economic analysis showed that the maximum net return was obtained due to soil test based phosphorus fertilizer recommendation .As a result determined Pc and Pf through , site specific soil test crop response based fertilizer study could be profitable for tef production in the study area and other areas having similar soil type and agro-ecology.