Resistance to TTKSK and TTTSK Races of Puccinia graminis f.sp. tritici in Ethiopian Tetraploid Wheat Accessions

Ethiopia is the leading wheat producing country in East Africa. East Africa is a known hotspot for the evolution of new rust races of wheat. A case in point could be the evolution of a new race of stem rust called Ug99 that overcame the resistance deployed in wheat breeding for stem rust for many decades. Tetraploid wheat is an excellent source of stem rust resistance. In Ethiopia recent race analysis works showed that races TTKSK and TTTSK are the two dominant races distributed in major wheat producing areas of the country such as Arsi and Bale. Taking this into account, searching for sources of stem rust resistance to races TTKSK and TTTSK is an important breeding strategy. Therefore, this study was conducted to identify sources of resistance to the two major stem rust races from tetraploid wheat accessions. A total of 40 tetraploid wheat accessions comprising Triticcum durum, T. diccoccum and T. turgidum were evaluated both at the seedling stage at Kulumssa and adult plant growth stages at Arsi Robe under natural epidemics. In the seedling stage, most of the accessions were resistant to both races. The infection type range from ; to 2+. 2+ is the maximum infection type that was displayed by few of the accessions. All the tetraploid accessions displayed low infection types to both races. Stem rust occurred at epidemic level at Arsi Robe compared to other testing locations. Almost half of the accessions were completely susceptible to stem rust infection in the field condition. Five accessions exhibited a completely immune reaction to the prevailing races. The rest displayed a trace level of moderately susceptible reaction. Those accession that combined seedling and adult plant resistance to stem rust infection could be utilized in the durum wheat breeding program of Ethiopia.   Keywords: Accessions, infection type, tetraploid, race, TTKSK, TTTSK

Contribution of Moringa Tree for Food Security and Management in Southern Ethiopia: Review

Consumption of diverse diets, with balanced supplies of macro and micro-nutrients is required for normal human growth and physiological development. However, availability of optimally diverse diets may be constrained by wealth and/or education (including loss of traditional knowledge of indigenous crops. Human diets have been inadvertently simplified in food  systems during the Green-Revolution era where agricultural production focused on provision of sufficient energy. In populations depending on cereal-based diets with low nutrient density, dietary simplification and shortage of access to animal source food exacerbates deficiency of vitamins and minerals, also known as hidden hunger. Moringa oleifera  and Moringa. stenopetala  are underutilized tropical tree species that can play an important role in dietary diversification and contribute to alleviation of hidden hunger in less developed tropical and subtropical countries .In particular, Moringa can be a rich source of some micronutrients that are commonly deficient in cereal-based diets. Keywords: Food, Tree, Moringa, olifera, Stenopetal ,Management DOI: 10.7176/JRDM/81-03 Publication date: December 31st 202

Functions in the Secondary School Mathematics Curriculum

Functions are used in every branch of mathematics, as algebraic operations on numbers, transformations on points in the plane or in space, intersection and union of pairs of sets, and so forth. Function is a unifying concept in all mathematics. Relationships among phenomena in everyday life, such as the relationship between the speed of a car and the distance travelled, are functions. The concept of function has an important part in the school mathematics curriculum; yet, many countries today are concerned with how to structure the curriculum. The first part of this brief provides a short background about the historical development of function in mathematics and its introduction into the school curriculum, explicating the ’identity crisis’ many countries are facing today. I then elaborate more on the goals for including functions in the school curriculum and on the learning about functions. I conclude this brief with challenges that policy makers, curriculum developers and teachers face and possibilities for meeting these challenges. Keywords: Function; Curriculum; teaching function; Learning Functio

Epidemics of Pucciniastriiformis F. Sp. Tritici in Arsi and West Arsi Zones of Ethiopia in 2010 and Identification of Effective Resistance Genes

Stripe rust of wheat is one of the most important wheat production constraints in Ethiopia. The 2010 main season has witnessed the importance of the disease as widespread epidemic occurred throughout the major wheat producing areas that resulted in complete crop failure and as a result two popular varieties Kubsa and Galama were withdrawn from production. In order to monitor stripe rust of wheat, wheat diseases survey are conducted annually and rust trap nurseries are planted in selected wheat producing areas. In the current study, survey was conducted to evaluate the performance of the released cultivars to the major epidemic on farmers’ wheat fields. Rust trap nurseries were also planted in major representative areas of the Arsi zone to evaluate the performance of the commercial cultivars and also the stripe rust differentials. A total of 120 wheat fields were covered during the survey. Stripe rust of wheat was the most prevalent disease across the three routes. It was found in 84% of the fields inspected. The incidence and the severity of stripe rust of wheat varied according to locations, varieties, planting dates and the crop growth stage. The highest stripe rust incidence and severity was recorded on Kubsa which is the dominant bread wheat cultivar in all the three routes. Stripe rust was quite high at altitudes ranging from 2144 to 2497m above sea level. Bread wheat cultivars such as Digalu, MadaWallabu and K62954A and Tusie were found to be resistant under farmers’ field condition and can serve as important sources of resistance to the stripe rust races prevailing in Ethiopia. Of the three test locations, Meraro has the widest virulence spectrum for stripe rust of wheat and as a result most of the stripe rust differentials were not effective to the stripe rust populations prevailing at Meraro. Kulumssa and Arsi Robe have comparable virulence spectrum and almost equal number of effective and ineffective genes were identified during the season in both locations. In general, compared to the other cropping seasons, the virulence spectrum of stripe rust has increased in 2010 in all locations and the number of effective genes identified is very low in all locations. The virulence spectrum of stripe rust at Meraro has always been wide because of the favorable environmental condition. Genes Yr5, Yr15 and YrSP were effective across all the test locations. These genes can be recommended to be utilized in the development of stripe rust resistant varieties that are effective to the Ethiopian stripe rust populations in the major wheat producing areas in Ethiopia. Keywords: effective genes, incidence, severity, stripe rust, trap nursery, virulence

Students’ Learning Experiences When using a Dynamic Geometry Software Tool in a Geometry Lesson at Secondary School in Ethiopia

Students learning experiences were investigated in geometry lesson when using Dynamic Geometry Software (DGS) tool in geometry learning in 25 Ethiopian secondary students.The research data were drawn from the used worksheets, classroom observations, results of pre- and post-test, a questionnaire and interview responses.  I used GeoGebra as a DGS tool with research questions relating to the aspects of (1) motivation, (2) interactions and discussions, (3) student-centered learning, (4) conceptual understanding, and (5) Problem _solving strategies. The questions were embedded in an instructional research intervention. The intervention comprised the use of worksheets and applets we developed through GeoGebra.The results showed that the use of a DGS tool with the presence of other factors, such as group work and the use of worksheets brought about certain changes in students ‘learning experiences’ of the geometrical concepts. Students were well motivated, but discussion and interaction were limited (due to time limitations) and results on students ‘conceptual understanding’ and problem-solving strategies were only partly satisfactory, but improved during the intervention. Keywords: Dynamic Geometry Software; GeoGebra; learning experiences; Conceptual Understanding; Problem – Solving Strategies

Students’ Misconceptions of the Limit Concept in a First Calculus Course

Misconceptions of the limit concept were examined in 130 pre-engineering students in Dilla Universities. Questionnaire and Interview were deigned to explore students understanding of the idea of a limit of a function and to explore the cognitive schemes for the limit concept.The study employed a quantitative-descriptive or survey design. The empirical investigation was done in two phases. A questionnaire on the idea of a limit was given to 130 students during the first phase. During the second phase 14 interviews were conducted. Then, the results indicated that students in the study see a limit as unreachable, see a limit as an approximation, see a limit as a boundary, view a limit as a dynamic process and not as a static object, and are under the impression that a function will always have a limit at a point. Regarding the relationship between a continuous function and a limit were: Students think that a function has to be defined at a point to have a limit at that point. A function that is undefined at a certain point does not have a limit; Students think that when a function has a limit, then it has to be continuous at that point. Other misconceptions were: The limit is equal to the function value at a point, i.e. a limit can be found by a method of substitution, when one divides zero by zero, the answer is zero, Most of the students know that any other number divided by zero is undefined. The study concluded that many students’ knowledge and understanding rest largely on isolated facts, routine calculation, memorizing algorithm, procedures and that their conceptual understanding of limits, continuity and infinity is deficient. The outstanding observation was that students see a limit as unreachable. This could be due to the language used in many books to describe limits for example ‘tends to’ and ‘approaches’. Another view of a limit that the students have is that a limit is a boundary point. This could be because of their experience with speed limits, although that could always be exceeded. Lecturers ought to become aware of their students’ understanding and possible misconceptions. Diagnosing the nature of students’ conceptual problems enables lecturers to develop specific teaching strategies to address such problems and to enhance conceptual understanding.Finally, the study suggested that concepts such as limit, involves a construction process, students build on and modify their existing concept images. Lecturers, in teaching the topic of limit, could develop concepts first before embarking on techniques in problem solving. Students need to conceptualize first before applying the formula. Keywords: Limit Concept, Misconceptions; Limits of functions; Concept Image; Concept Definitio

Transitional Justice in the Context of Ethiopia

Leadership and governance are very important aspects of living in any civilized society. It is however, imperative to note that leadership unfolds over time in different models, ideologies and approaches, by the different leaders. This gives connotation to the concept of transitional justice to ensure a smooth and meaningful change of power or leadership from one model or person to another to avoid despotism and anarchy. This paper debates the ideology of transitional justice and its focus on the subject of how societies should transit from authoritarian rule to democracy in order to address a persistent history of massive human rights abuses. This piece of work brings light on how societies across the world ought to deal with their evil pasts. The paper fronts Ethiopia as a case study to have an in-depth perspective of the trends and dynamics involved in transitional justice. The discussion is specifically limited on Ethiopia, focusing mainly on the transition which took place in 1991. The paper circumspectly handles key democratic issues in governance and in that respect shades light on what the concept of transitional justice is and its implications in governance and social relations of any country. It gives insights into how Ethiopia dealt with its past after the transition, discusses the lessons learnt, and the common alternatives always available to both government leaders and the populace in dealing with their past

Students’ Learning Experiences When using a Dynamic Geometry Software Tool in a Geometry Lesson at Secondary School in Ethiopia

Students learning experiences were investigated in geometry lesson when using Dynamic Geometry Software (DGS) tool in geometry learning in 25 Ethiopian secondary students.  The research data were drawn from the used worksheets, classroom observations, results of pre- and post-test, a questionnaire and interview responses.  I used GeoGebra as a DGS tool with research questions relating to the aspects of (1) motivation, (2) interactions and discussions, (3) student-centered learning, (4) conceptual understanding, and (5) Problem _solving strategies. The questions were embedded in an instructional research intervention. The intervention comprised the use of worksheets and applets we developed through GeoGebra. The results showed that the use of a DGS tool with the presence of other factors, such as group work and the use of worksheets brought about certain changes in students ‘learning experiences’ of the geometrical concepts. Students were well motivated, but discussion and interaction were limited (due to time limitations) and results on students ‘conceptual understanding’ and problem-solving strategies were only partly satisfactory, but improved during the intervention. Keywords: Dynamic Geometry Software; GeoGebra; learning experiences; Conceptual Understanding; Problem – Solving Strategies

Students Difficulties of Solving Inequalities in Calculus

The study tries to analyze the students’ difficulties and explore the errors done by the students when finding solution sets for inequalities. For these purpose a test was given to college of natural and computational science students who have taken calculus I or applied mathematics I course in Dilla University, Ethiopia. The results showed that the students are not successful in solving inequalities. The mostly observed mistake was to multiply both sides of inequality by expression that includes variable without paying attention to the sign of this expression. Moreover, significant number of procedural and technical errors is made by the students

Vulnerability of household livelihoods to climate variability and change in the central rift valley sub-basin of Ethiopia

Ethiopia, despite contributing minimally to global greenhouse gas emissions, is consistently cited as one of the most vulnerable countries, not only in Sub-Saharan Africa regions but also globally, to climate variability and change. The country's farming households are most vulnerable because of their climate-sensitive livelihoods and limited resources to finance adaptation measures. This study aimed to assess the livelihood vulnerability of communities reliant on a mixed crop-livestock agricultural system and natural resources in the Central Rift Valley sub-basin of Ethiopia to climate variability and change. Structured interviews were used to collect quantitative data from 339 randomly selected households. Livelihood Vulnerability Index was developed to assess the degree of livelihood vulnerability between the two districts. The survey results were supported and substantiated by focus group discussions. The findings show that farm households living in the sub-basin experience different levels of vulnerability to climate variability and change because of their varying adaptive capacities. Considering the aggregate Livelihood Vulnerability Index, Arsi Negele district is considered to be more vulnerable to climate variability and change. The livelihood Vulnerability Index-Intergovernmental Panel on Climate Change results also show that Arsi Negele is more vulnerable since its exposure scores exceed its adaptive capacity. Several factors contribute to the weak adaptive capacity of farmers in Arsi Negele. These factors include lesser adoption of agricultural technology, a low level of knowledge and education, insufficient social networks, less diversification of livelihood strategies, and higher socio-demographic vulnerability. In contrast, Adami Tullu Jido Kombolcha district has a higher sensitivity score due to its limited access to potable water, housing, and land ownership. Strategies that minimize households' degree of sensitivity and enhance their adaptive capacity should be promoted. Such strategies should include the adoption of improved agricultural technologies, strengthening awareness and technical capacity, promoting better soil and water management, accessing credit options, and building community networks. Diversifying household income and establishing alternative livelihoods should also be encouraged