Adult Mosquito Populations and Their Health Impact around and far from Dams in Tigray Region, Ethiopia

Malaria control program in Ethiopia has a history of more than 40 years, but still now, malaria is a major cause of morbidity and mortality in Ethiopia. The objective of this study is to assess the impact of dam construction in the distribution of mosquito in intervention (dam nearby villages) and controlled (villages far from dam). Indoor adult mosquitoes were collected using 144 CDC light traps from 12 villages (6 from the intervention and 6 from the control villages) Community- based malaria parasitology was also done. Sampling was done in November 2005, December 2005, May 2006 and September 2006). A total of 1713 adult indoor mosquitoes were collected, of these, 1182 (69%) were Anopheles and 531 (31%) Culex. The prevalence of Anopheles was 45.77% in the intervention villages and 23.23% in the controlled villages (F p = 0.012). The prevalence of Anopheles increased twice in the intervention compared to the controlled villages. A total of 1436 children, 888 from intervention and 548 from control villages were examined for malaria parasitology. Only 57 children were found infected by Plasmodium species. Malaria prevalence rate was 3.97% (4.17% and 3.65% in intervention and control village, respectively)(x2 = 0.11, p= 0.7399). Among the 57 malaria positive cases in 32 (56.14%) we found P. vivax and in the 25 (43.86%) P. falciparum. We can tentatively conclude that the dams situated at 2000m and above do resulted two fold adult indoor mosquito, but do not seem to have resulted in a markedly higher incidence of malaria in the region. The study concludes that concerned authorities should take appropriate measures to improve health-care facilities for local communities when planning new irrigation schemes wherever they occur.Keywords: Anopheles, Culex, Dam, Intervention, Malari

A Dynamic Sorghum (Sorghum Bicolor (L.) Moench) diversity Management in Situ and Livelihood Resilience in South and Central Tigray Region, Ethiopia

Sorghum is an important crop for the south and central parts of Tigray Region of Ethiopia. To assess the level of sorghum diversity, two zones, namely South and Central Tigray were selected and eighteen villages in three woredas, Alamata, Raya-Azebo and Tanqua-Abergelle, were surveyed. A total of 93 randomly selected farmers were interviewed using a structured questionnaire that elicited information on socioeconomic aspects of households, sorghum plots, the number and types of farmers’ local varieties grown in the area, variety characteristics, seed exchange systems and seed flow together with selection criteria’s as well as seed selection process and management. A total of 165 collections belonging to 31 locally named sorghum varieties were retrieved and stored at Mekelle University. High diversity in terms of landrace richness were found the Alamata area (Margalef = 2.92; Menhinick = 1.66) followed by Raya-Azebo (Margalef = 2.61; Menhinick = 1.46) and Tanqua-Abergelle was found to be less diverse in terms of number of named varieties (Margalef = 1.40; Menhinick = 1.0). Diversity estimated based on evenness indices showed that Tanqua-Abergelle has the highest diversity (Shannon =0.86; Brillouin index = 0.86) followed by Raya-Azebo (Shannon =0.85; Brillouin index = 0.85). The lowest evenness was found in Alamata woreda (Shannon =0.77; Brillouin index = 0.77). Based on the varietal richness and use values, four sites (villages) that could serve as seed repositories were identified. The result of the econometric analysis indicated that a combination of factors, such as year of schooling, labour equivalence, tropical livestock unit, and number of parcels were the most important determinants that affect significantly the intra-specific diversity. The regression analysis indicates the positive linkage between land fragmentation and landrace richness. The increase in diversity over temporal scale of ten years found in this study revealed that the level of genetic erosion needs numerical evidence to substantiate. The socioeconomic factors that affect varietal diversity and possible conservation and incentive strategies are discussed. Key words: Sorghum, Diversity, Seed flow, Genetic erosion, Resilienc

Enhancing Productivity and Production of Onion (Allium cepa L.) Through the use of Improved Varieties at North Western Zoze of Tigray, Ethiopia

Field experiment was conducted to study the effect different varieties on yield, yield attributing character and postharvest storability of onion (Allium cepa L.) in Tselemti district, North western Zone of Tigray During 2007-2009off season time. Four improved onion varieties namly:Bombey red, Adama red, Nasik red &Nafis including Shendi (imported from Sudan),were tested in Randomized Complete Block Design (RCBD) with four replications. Accordingly, treatments were assigned randomly to the experimental plot within a block. The results showed that the difference in variety had significant effect on all characters except the non-significant effect of variety on neck thickness and bulb diameter. Nasik red variety gave significantlyhighest in plant height ,leaf number, leaf length bulb length and marketable bulb yield i.e 35588kg/ha that exhibited 18% and 36% advantages on the dominantly produced varieties bombey red and adama red respectively.The overall study revealed that growing Nasik red variety is not only significantly increased the marketable bulb yield , but also better shelf life. Therefore, it is recommended for onion producers of Tselemti wereda for profitable onion yiel

Characterization of crop residues from false banana/Ensete ventricosum/in Ethiopia in view of a full-resource valorization

Research ArticleFalse banana /Ensete ventricosum [Welw.] Cheesman/ is exploited as a food crop in Ethiopia where it represents an important staple food. The plant is harvested and large amounts of biomass residues are originated, mainly from the pseudo stem (i.e., fiber bundles obtained from the leaf sheaths after being scrapped to produce starchy food) and the inflorescence stalk. These materials were studied in relation to their summative chemical composition, composition of lignin, lipophilic and polar extracts. Moreover, their structural characteristics, in view of their valorization, were scrutinized. The analytical studies were performed with the aid of FTIR, GC/MS, Py-GC/MS and SEM. The fiber bundles are aggregates of mainly long and slender fibers with low ash, extractives and lignin contents (3.8%. 4.4% and 10.5% respectively) and high holocellulose and α-cellulose contents (87.5% and 59.6% respectively). The hemicelluloses in the fibers are mostly highly acetylated xylans and the lignin is of the H-type (H:G:S, 1:0.7:0.8). This lignin composition is in line with the FTIR peaks at 1670 cm-1 and 1250 cm-1.The inflorescence stalk has high ash content (12.3% in the main stalk and 24.6% in fines) with a major proportion of potassium, high extractives (25.9%), and low lignin and α-cellulose contents (5.8% and 17.9% respectively). The stalk includes numerous starch granules in the cellular structure with the predominant presence of parenchyma. The potential valorization routes for these materials are clearly different. The fiber bundles could be used as a fiber source for paper pulp production with the possibility of a prior hemicelluloses removal while the inflorescence stalk has nutritional value for food and fodder. Furthermore, it can also be used for sugar fermentation productsinfo:eu-repo/semantics/publishedVersio

High flux electroneutral loose nanofiltration membranes based on rapid deposition of polydopamine/polyethyleneimine

© 2017 The Royal Society of Chemistry. A rational manipulation of the surface structures and properties of thin-film composite membranes is important to optimize their separation performance and service durability. In this study, a facile strategy is reported for fabricating electroneutral loose nanofiltration membranes based on the rapid co-deposition of biomimetic adhesive polydopamine and poly(ethylene imine) (PEI) by using CuSO4/H2O2as a trigger. Through this strategy, the surface properties and the filtration performance of the membranes can be easily tailored by the addition of PEI and CuSO4/H2O2, as well as tuning the deposition time. UV, XPS, SEM, AFM, zeta potential, water contact angle and nanofiltration measurements were used to investigate membrane performance. Surface characterization revealed that overall enhanced surface properties including low roughness, favourable hydrophilicity, and relatively neutral charge can be achieved after the addition of PEI. The optimum membranes, with 1 h co-deposition of PDA and PEI, show an ultrahigh water permeability (26.2 L m-2h-1bar-1), distinguished rejection for both negatively and positively charged dyes and a high permeation of divalent salts (>90%). Furthermore, the optimum membranes also show excellent operational stability in long-term nanofiltration operations in alkaline solution. This study provides an efficient and facile approach to tailor the membrane properties and structure for loose nanofiltration membranes