Assessments of Alfalfa (Medicago sativa) and Rhodes grass (Chloris gayana) at Soddo and Kedidagamila districts of southern Ethiopia

Assessments of Rhodes grass (Chloris gayana) and Alfalfas (Medicago sativa) was carried out on 36 farmers fields in soddo and kedidagamila districts of Southern Ethiopia during 2010/2011 cropping season in order to test the adaptability of grass and legume forages, create awareness to the farmers and evaluate the yield performance of the technologies by farmers evaluation criteria. The range and mean performance of annual grass and legume forages have showed considerable amount of variability among the traits. For instance, fresh biomass yield of rhodes grass varied from 31.9-98.0 and 27.8-39.3 tones/ha for soddo and Kedidagamila districts respectively. The plant height and number of branch/plant of rhodes grass also varied from 128.9-172.9cm and 4.0-16.0 for soddo and 110.8- 129.5 cm and 7.0-16.0 for Kedidagamila. Moreover, the fresh biomass yield of alfalfa in soddo is varied from 21.9-44.1 and 22.1-34.30 t/ha and dry matter 8.26-23.26 and 10.6-17.6 t/ha for soddo and Kedidagamila districts respectively. Based on farmers evaluation, both alfalfa and Rhodes grass are the most vigorous, persistent and highly adapted species, and thus can be safely suggested for the soddo district. Furthermore, the growth performance of Rhodes grass in kedidagamila also good but, productivity of alfalfa was poor and this probably resulting from unfavorable climatic conditions. The over all mean of the result, 90.26% and 69.43% of soddo farmers were selected rhodes grass and alfalfa. In kedidagamila, 88.88 % of the farmers were preferred Rhodes grass over 40.25 % of alfalfa. Key words: Assessments, adaptation,  Evaluation Medicago sativa, Chloris gayan

Assessments of Alfalfa (Medicago sativa) and Rhodes grass (Chloris gayana) at Soddo and Kedidagamila districts of southern Ethiopia

Assessments of Rhodes grass (Chloris gayana) and Alfalfas (Medicago sativa) was carried out on 36 farmers fields in soddo and kedidagamila districts of Southern Ethiopia during 2010/2011 cropping season in order to test the adaptability of grass and legume forages, create awareness to the farmers and evaluate the yield performance of the technologies by farmers evaluation criteria. The range and mean performance of annual grass and legume forages have showed considerable amount of variability among the traits. For instance, fresh biomass yield of rhodes grass varied from 31.9-98.0 and 27.8-39.3 tones/ha for soddo and Kedidagamila districts respectively. The plant height and number of branch/plant of rhodes grass also varied from 128.9-172.9cm and 4.0-16.0 for soddo and 110.8- 129.5 cm and 7.0-16.0 for Kedidagamila. Moreover, the fresh biomass yield of alfalfa in soddo is varied from 21.9-44.1 and 22.1-34.30 t/ha and dry matter 8.26-23.26 and 10.6-17.6 t/ha for soddo and Kedidagamila districts respectively. Based on farmers evaluation, both alfalfa and Rhodes grass are the most vigorous, persistent and highly adapted species, and thus can be safely suggested for the soddo district. Furthermore, the growth performance of Rhodes grass in kedidagamila also good but, productivity of alfalfa was poor and this probably resulting from unfavorable climatic conditions. The over all mean of the result, 90.26% and 69.43% of soddo farmers were selected rhodes grass and alfalfa. In kedidagamila, 88.88 % of the farmers were preferred Rhodes grass over 40.25 % of alfalfa. Key words: Assessments, adaptation,  Evaluation Medicago sativa, Chloris gayan

Development of high temperature mechanical rig for characterizing the viscoplastic properties of alloys used in solid oxide cells

Analyzing the thermomechanical reliability of the solid oxide cell (SOC) stack requires precise measurement of the mechanical properties of the different components in the stack at operating conditions of the SOC. It is challenging to precisely characterize the time-dependent deformational properties of metallic components in the SOC stacks at the required level of stress and operational conditions (high temperature and controlled atmosphere). This work presents an improved methodology for characterizing the time-dependent, or viscoplastic, properties of metallic alloys used in the SOC stacks at a high temperature and in a controlled atmosphere. The methodology uses a mechanical loading rig designed to apply variable and constant loads on samples within a gas-tight high temperature furnace. In addition, a unique, remotely installed length measuring setup involving a laser micrometer is used to monitor deformations in the sample. Application of the methodology is exemplified by measurement of stress relaxation, creep, and constant strain rate behaviors of a high-temperature alloy used in the construction of SOC metallic interconnects at different temperatures. Furthermore, measurements using the proposed methodology are also verified by the literature and experiments conducted using other machines

Effects of different dose of nitrogen and lime on soil properties and maize (Zea mays L.) on acidic nitisols of Northwestern Ethiopia

This study was carried out on the nitisols of Burie district, Ethiopia to examine the effect of integrated use of lime and nitrogen on soil physicochemical properties and maize yield. Two levels of lime (0 and 0.5 t/ha) and five-level of nitrogen (0, 46, 92, 138 and 184 kg N/ ha) were laidout in randomized complete block design with three replications. The results indicated that among before planting, soil bulk density (BD), pH, soil organic carbon (OC), total nitrogen (TN), available P and CEC were 1.42 g/cm3, 5.2 (strongly acidic), 1.32% (very low), 0.12% (low), 8.86 mg /kg (very low), and 19.57 cmolc /kg  (medium), respectively.  The physicochemical properties except bulk density increased. The lowest soil BD (1.21 g/m3) was from plots treated with 0.5 t/ha lime and 184 kg N/ ha. The maximum soil pH (6.85) was obtained from plots treated with 184 kg N/ ha and 0.5 t/ha lime. The maximum soil CEC (35.38 (cmolc /kg) was obtained from plots treated with 184 kg N/ ha and 0.5 t/ha lime. Level of lime, nitrogen fertilizer, and interaction effects of lime and nitrogen fertilizer (L×N) significantly affected maize yield (p<0.001). Indeed yield of maize has positive correlations with most soil physicochemical properties but negative with BD (r= -0.543). The adjusted yield and net benefits was 6.4 t/ha and 1101.77$. Inherent physicochemical properties of the soil are changed either by sole or combined use of lime and N fertilizer. Soils tilled with 0.5 t/ha lime and 138 kg/ha  nitrogen were found in maximum net benefit. Residual long-term effects should be researched. Thus, liming should be given an emphasis on acidic soil amelioration. Moreover, the government may facilitate the supply of lime and nitrogen fertilizer to the farmers.