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Effect of Potassium Levels on Growth and Productivity of Potato Varieties

American Journal of Plant Sciences 2016年第12期7卷 1629-1638页

作者： Daniel Zeru Zelelew Sewa Lal Tesfai Tsegai Kidane biniam mesfin ghebreslassie Department of Horticulture Hamelmalo Agricultural College Keren Eritrea Department of Agricultural Economics Hamelmalo Agricultural College Keren Eritrea Department of Horticulture Jomo Kenyatta University of Agriculture and Technology Juja Kenya

Potato is one of the priority vegetable crops in the highlands of Eritrea growing as a key component in the livelihood systems of farmers. Potato requires a variety of balanced plant mineral nutrients for growth and development without which yield and qualities of tubers are reduced. Potato growers in Eritrea commonly use Di-ammonium Phosphate, Urea and Farmyard manure while potassium fertilizers are overlooked assuming that the soil is developed from K rich parent material and contains sufficient amount of K to support crop growth. However this assumption is based on the result obtained forty-seven years ago. As a result the yield and quality of potato produced is very low as compared with international standards. Therefore the present experiment was conducted to assess the effect of potassium levels on growth and productivity of potato varieties at Hamelmalo Agricultural College, Eritrea. The experiment was conducted in factorial Randomized Complete Block Design with fifteen treatment combinations of three varieties (Ajiba, Zafira and Picasso) and five potassium levels (0, 75, 150, 225 and 300 kg K2O/ha) replicated thrice. The results of the study showed that both variety and potassium had significant effect on growth and yield parameters. Aerial stem number, leaf number per plant and plant height were increased with increasing K levels from 0 to 150 kg while number of days to maturity was increased in the range of 0 - 300 kg K2O/ha. The result also indicated that variety Ajiba treated with 300 kg K2O/ha produced significantly highest tuber weight (1.14 kg) per plant and tuber yield of 49.38 t/ha. The economic analysis result revealed that maximum gross margin 13,665.816 USD/ha was obtained from the application of 300 kg K2O/ha. On the whole, it gives an impression that using potassium fertilizer according to soil requirements will have good influence on growth and tuber yield.

关键词： Eritrea Potassium Potato Varieties Tuber Yield

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Effect of Moisture Conservation Methods and Plant Density on the Productivity of Two Maize (<i>Zea mays</i>L.) Varieties under Semi-Arid Tropics of Hamelmalo, Eritrea

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American Journal of Plant Sciences 2017年第1期8卷 28-39页

作者： Shimendi Gde Okbagabir N. N. Angiras biniam mesfin ghebreslassie Department of Agronomy Hamelmalo Agricultural College Keren Eritrea Deprtment of Horticulture Jomo Kenyatta University of Agriculture and Technology Juja Kenya

The productivity of maize in Eritrea in general and under semi-arid tropics of Hamelmalo in particular is low because of moisture stress. The low moisture content is ascribed to the low and erratic distribution of rainfall, high temperature, lack of suitable varieties, and competition by weeds and low soil fertility. To overcome some of these problems, a field experiment was carried out to assess the effect of moisture conservation methods (MCM) and plant density on the productivity of two maize (Zea mays L.) varieties under semi-arid tropics of Hamelmalo, Eritrea. The experiment was conducted in split-split plot design with three MCM viz tied ridge, ridge and furrow and flat-bed in main plots;two maize varieties viz early local and 04sadve hybrid in sub plots and three plant densities by manipulating the plant to plant distance viz 35 cm, 25 cm and 15 cm at a fixed 75 cm row spacing in sub-sub plots, each replicated thrice. The experiment was focused in addressing the effective moisture conservation techniques, optimum plant density to each variety thus to improve productivity. The crop experienced 10°C to 34.8°C minimum and maximum temperature, respectively and received 429.1 mm total rainfall. The results of the experiment indicated that among all the combinations, 04sadve hybrid variety sown at 75 cm × 25 cm spacing in ridge and furrow method or at 75 cm × 15 cm spacing in tied ridge or flat-bed method and early local variety sown at 75 cm × 15 cm spacing in flat-bed being statistically at par resulted in significantly higher moisture conservation and consequently higher grain yield (4509 kg·ha-1) and higher water use efficiency. It is, therefore, recommended that tied ridge or flat-bed of moisture conservation method at 15 cm plant spacing and 04sadve is preferable to optimize productivity in Hamelmalo area, Eritrea.

关键词： Eritrea Moisture Conservation Methods Maize Varieties Water Use Efficiency

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Analysis of Diversity among Potato Accessions Grown in Eritrea Using Single Linkage Clustering

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American Journal of Plant Sciences 2015年第13期6卷 2122-2127页

作者： biniam mesfin ghebreslassie S. Mwangi Githiri Tadesse Mehari Remmy W. Kasili Department of Horticulture Hamelmalo Agricultural College Keren Eritrea Department of Horticulture Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Institute of Biotechnology Research Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

Potato is an important cash and food crop, a source of income to many small scale farmers in Eritrea. In the long tradition of potato cultivation farmers have adopted a number of landraces. However, very little is known about their genetic diversity which limits further breeding programs to improve productivity. The objective of the study was to characterize potato accessions grown in Eritrea. A total of 21 accessions collected from farmers and NARI were used in this study for characterization employing 33 phenotypic descriptors. Single linkage (nearest neighbor) clustering method using UPGMA employing Euclidean test was used to yield a dendrogram. The clustering generated three main clusters with further sub clusters. The clustering helped to identify accessions that shared the same characteristics and/or that were closely related and vice versa. It was noted that there was no distinct relationship between the clusters groups and geographic sources of accession. Yet, accessions sharing the same name may not necessarily share the same genetic content. Mean deviation of variables for each group from the total mean indicated that Group III followed by group I showed negative deviation in most of the recorded yield related traits. Group I was particularly affected by the presence of two inferior accessions in the group. On the other hand, Group II accessions showed relatively maximum deviation from the total mean and could be recommended for use as parent for any breeding program in Eritrea.

关键词： Solanum tuberosum Potato Eritrea Morphological Traits Cluster Diversity

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Potato Seed Supply, Marketing and Production Constraints in Eritrea

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American Journal of Plant Sciences 2014年第24期5卷 3684-3693页

作者： biniam mesfin ghebreslassie S. Mwangi Githiri Tadesse Mehari Remmy W. Kasili Department of Horticulture Hamelmalo Agricultural College Keren Eritrea Institute of Biotechnology Research Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Department of Horticulture Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Institute of Biotechnology Research Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya

Potato is an important vegetable crop in Eritrea contributing significantly to food security. Despite its importance, however, production and thus supply of the crop in the market are limited. The current study is designed to understand the seed supply system, marketing out lets and major production constraints. The survey was conducted in the two main potato producing Zobas of the country (Zoba Maekel and Zoba Debub). Qualitative and quantitative data was generated using focus group discussion (PRA) and semi structured questionnaire, respectively. A total of 20 villages were visited and 138 farmers were interviewed. The finding revealed that there is no standard seed supply system thus majority (91.3%) of the growers purchase seed from open market with a limited supply from the Ministry of Agriculture. Furthermore, about 63% of the farmers from Zoba Maekel reserve their own seed for the next cycle compared to 53.6% from Zoba Debub. It was noted that the Tsaeda embaba variety grows predominantly in the country owing to its yield and resistance. Majority of the growers rely on tuber colour and shape for variety identification, thus over 76% prefer the round shaped and white coloured variety. The potential marketing outlets include wholesale, retailer and direct to consumers. Majority (78.3%) of the interviewed growers indicated that large portion of their produce is marketed via wholesaler followed by retailers (27.5%). Main production limiting constraints are identified as low input supplies, availability and cost of clean seeds, pest pressure while huge market demand and access to transportation are considered as potentials encouraging grower. It is, therefore, recommended that an immediate action to establish sustainable seed supply system is taken into consideration in line with a regular extension service to provide technical advice to growers.

关键词： Potato Seed Source Marketing Constraints Potentials

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Vegetation structure and regeneration status of the moist,evergreen, afromontane Bore–Anferara–Wadera forest in southern Ethiopia

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Journal of Forestry Research 2020年第3期31卷 953-967页

作者： mesfin Woldearegay Zerihun Woldu Department of Biology College of Natural and Computational SciencesDebre Birhan UniversityP.O.Box 445Debre BirhanEthiopia Department of Plant Biology and Biodiversity Management Addis Ababa UniversityP.O.Box 3434Addis AbabaEthiopia

In a survey of the Bore–Anferara–Wadera forest to study the vegetation structure and regeneration status of woody plant species, 112 quadrats were systematically sampled along altitudinal transects to collect vegetation data. Nested sample plots of 30 m × 30 m and 5 m × 5 m were laid for collecting data on abundance and some variables of tree and shrub size. The regeneration status of woody species was assessed by counting all seedlings within the main sample plot. Woody plant species taller than or equal to 3 m were counted and their height and DBH measured. Density, frequency, basal area and importance value(IV) of woody plant species were computed. A total of 136 vascular plant species belonging to119 genera and 63 families were recorded. The overall Shannon—Wiener diversity value was 3.84 and evenness was 0.78. Total density of trees and shrubs with DBH >2 cm was 1047 ha-1. Size class distribution of woody species across different DBH and height classes indicated a relatively high proportion of individuals at lower classes,suggesting impacts of past anthropogenic *** of population structure and regeneration status of the forest revealed various patterns of population dynamics where some species were represented by only a few mature plants, suggesting that they are on the verge of local extinction and that immediate conservation measures should be taken. The results highlight the need for joint management and conservation measures by the government, local people and other stakeholders to abate the rapid rate of deforestation and promote sustainable utilization of the forest resources in this forest in southern Ethiopia.

关键词： Anferara Afromontane forest Conservation Regeneration Structural analysis

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Choices of Varieties and Demand for Improved Rice Seed in Fogera District of Ethiopia

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Rice science 2018年第6期25卷 350-356页

作者： A.H.mesfin L.ZEMEDU Agricultural Economics Research Ethiopian Institute of Agricultural Research/Agricultural Research Center Agricultural Economics Research Ethiopian Institute of Agricultural Research/Debrezeit Agricultural Research Center

In this study, 151 households were randomly drawn from three randomly selected Kebele in probability proportional to size method. The demographic and socio-economic factors that determine the participation in improved varieties were household labor availability, education level of the household head,land holdings, distance to the nearest village market, proximity to the main market, and distance to access agricultural extension and access to the source of rice seeds. However, determinants of choice decision varied from cultivar to cultivar. The evidence of the study from the interdependence among the decision of adoption of improved rice varieties suggested that technology adoption will be accelerated by launching a progressively developing package and scheme of rice technology generation, and points to the importance of mobilising additional resources to augment households' efforts at popularization and promotion of improved rice *** findings from Linearized Almost Ideal Demand Systems(LA/AIDS) model showed that compelling evidence for small proportion changes in own prices and cross price of improved rice varieties led to greater than unitary proportionate changes in their purchases. The results generally showed that farmers were very sensitive to changes in improved rice seed prices and incomes. The major implication of the findings was that any intervention to improve farmers' seed purchases should take into account efforts to increase farmers' purchasing power of agricultural inputs like improved seeds and fertilizers.

关键词： improved rice choice seed demand multivariate probit Linearized Almost Ideal Demand Systems

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Characterization of mycobacterium isolates from pulmomary tuberculosis suspected cases visiting Tuberculosis Reference Laboratory at Ethiopian Health and Nutrition Research Institute,Addis Ababa Ethiopia:a cross sectional study

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Asian Pacific Journal of Tropical Medicine 2015年第1期8卷 35-40页

作者： biniam Mathewos Nigatu Kebede Tesfu Kassa Adane Mihret Muluwork Getahun Department of Immunology and Molecular biology School of Biomedical and Laboratory SciencesCollege of Medicine and Health SciencesUniversity of Gondar Aklilu Lemma Institute of Pathobiology College of Health SciencesAddis Ababa University Armaour Hanson Research Institute Ethiopian Health and Nutrition Research Institute

Objective:To characterize mycobaclerium isolates from pulmomary tuberculosis suspected cases visiting National Tuberculosis Reference Laboratory at Ethiopian Health and Nutrition Research Institute,for diagnosis of pulmonary tuberculosis from January 4 to February 22.2010 with total samples of ***:Sputum specimens were collected and processed:the deposits were *** culturing Lowenstein Jensen medium(LJ) and Mycobacteria Growth Indicator Tube(BACTEC MGIT 960) were *** Neo was used for detecting NTM isolates from isolates of BACTEC *** Armauer Hansen Research Institute,Addis Ababa Ethiopia,Deletion typing PCR method for species identification(from confirmed Mycobacterium tuberculosis complex(MTBC) isolates by Capilia Neo) uas ***:Out of 263 enrolled in the study.124 and 117 ol them were positive for mycobaeterium growth by BACTEC MGIT 960 and 1.1 culture method,*** BACTEC MGIT 960 positive media of 124 isolates.117 were randomly taken to perform Capilia TB Neo *** these 7(6%) of them were found to be NTM and 110(94%) were *** these 110 MTBC isolates,81 of them were randomly taken and run by the deletion typing RD9 PCR method of molecular *** of these 78(96.3%) were found to be species of Mycobacterium tuberculosis and 3(3.7%) were found to be not in the *** the types of methods of culture *** Growth Indicator Tube(BACTEC MGIT 960) method was found to have excellent agreement(with kappa value ol 0.78) with the routine method of ***:Pulmonary tuberculosis suspected cases visiting the National Tuberculosis Reference Laboratory at EHNR1 that were confirmed to be pulmonary tuberculosis are caused by the species of Mycobacterium *** treatment regimen including pyrazinamide can be applied to the patients as the first choice in the study area in Addis *** is indication of the presence of NTM in patients visiting the tuberculosis ref

关键词： NTM Mycobacterium tuberculosis complex Mycobacteria growth indicator tube Lowenstein Jensen media

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Characteristics of soil quality attributes under different agroecosystems and its implications for agriculture in the Choke Mountain watershed in Ethiopia

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 303-313页

作者： Demeku mesfin Engdawork ASSEFA Belay SIMANE College of Development Studies Center for Environment and DevelopmentAddis Ababa UniversityAddis Ababa 1000Ethiopia College of Social Science and Humanities Department of Geography and Environmental StudiesWolaita Sodo UniversityWolaita Sodo 4620Ethiopia

Awareness of how soil properties vary over agroecosystems(AES) is essential for understanding soil potentials and improving site-specific agricultural management strategies for a sustainable ecosystem. This study examined the characteristics of soil quality attributes and implications for agriculture in the Choke Mountain watershed in Ethiopia. Forty-seven composite soil samples(0–20 cm deep) were collected from lowland and valley fragmented(AES 1),midland plain with black soil(AES 2), midland plain with brown soil(AES 3),sloppy midland land(AES 4), and hilly and mountainous highlands(AES 5).Ten of 15 soil quality properties were significant(P < 0.05 or 0.01), including silt, exchangeable bases, cation exchange capacity, percent base saturation,p H, organic matter, total nitrogen and available phosphorous(P) across the five AES. However, all properties were variable with coefficients of variation from 7%(total porosity) to 169%(available P) across the AES. Although AES 2and 3 are affected by waterlogging and acidity, these two have better prospects for agriculture, but AES 1, 4, and 5 are unsuitable for agriculture because of soil erosion. Therefore, appropriate and applicable soil management strategies, particularly lime application and organic fertilizer, are fundamental to reversing soil acidity and improving soil fertility.

关键词： Agroecosystem Choke Mountain watershed coefficients of variation Ethiopia soil quality indicator

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Superluminal light attenuated by strong dispersion of complex refractive index

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Chinese Physics B 2016年第2期25卷 477-481页

作者： Abdurahman Ahmed Yonis Vadim Nickolaevich Mal'nev Belayneh mesfin Ali Department of Physics Addis Ababa University

The propagation of narrow packets of electromagnetic waves（EMWs） in frequency dispersive medium with the consideration of the complex refractive index is studied. It is shown that counting in the dispersion of the complex refractive index within the context of the conventional expression of the group velocity of narrow wave packets of EMWs propagating in a dispersive medium results in the appearance of additional constraints on the group velocity, which dictates that the physically acceptable group velocity can only be realized in the case of a negligible imaginary part of the group index. In this paper, the conditions that allow one to realize the physically acceptable group velocity are formulated and analyzed numerically for the relevant model of the refractive index of a system of two-level atoms in the optical frequency range. It is shown that in the frequency band where superluminal light propagation is expected, there is a strong dispersion of the refractive index that is accompanied with strong absorption, resulting in a strongly attenuated superluminal light.

关键词： group velocity group index superluminal light slow waves

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Carbon Nanotube-Textured Sand for Controlling Bioavailability of Contaminated Sediments

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Nano Research 2010年第6期3卷 412-422页

作者： Xingmao Ma Deepti Anand Xianfeng Zhang mesfin Tsige Saikat Talapatra Department of Civil and Environmental Engineering Southern Illinois University CarbondaleIL 62901USA Department of Physics Southern Illinois University CarbondaleIL 62901USA

Sand particles textured with multi-walled carbon nanotubes (MWCNTs) can efficiently control the mobility and bioavailability of contaminants found in aquatic sediments. Adsorption measurements for a wide variety of aquatic contaminants (chlorinated hydrocarbons) on MWCNT-textured sand showed orders of magnitude increase in their sorption coefficients compared to traditional materials (sand) when used for physically separating contaminated sediments from overlying water. Molecular dynamics simulations performed on model experimental systems emphasize that the hydrophobic interactions of the MWCNT surfaces play a crucial role in driving the water molecules away, promoting such enhanced contaminant uptake. The MWCNT-textured sand significantly reduced the migration of contaminants from sediments to overlying water and possesses suitable parameters needed for contaminant sequestration and sediment remediation technologies. The single step and scalable procedure described here for synthesizing robust MWCNT-textured sand surfaces will provide important improvements in the field of remediation/aquatic environment restoration technologies.

关键词： Multi-walled carbon nanotube(MWCNT)-textured sand in situ capping capping amendments chlorinated compounds

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