General Biology

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Some Monogenic Morphogenetics Traits Frequency Among Students of Dagmawi Berhan Primary School Addis Ketema Sub City Addis Ababa Ethiopia
(Addis Ababa University, 2022-03-28) Demsew, Alemshet; Beyene, Dereje (PhD)
Morphological traits are a structural characteristic of an organism that is determined genetically and transmitted from parent to offspring. Some of these characteristics, such as tongue rolling, widow's peak hairline, bent little finger, and ear lobe attachment, are thought to be exact epitome of simple dominant and recessive patterns of transmission; as a demonstration of how Mendelian genetics works, they are clear, and easy to follow epitomes. Thus, these traits were little to No study conducted and documented in Ethiopian population. So, this study has its own contribution to asses and documents the data for next studies as reference. The general objective of this study was to investigate the distribution and frequencies of the morphological traits of tongue rolling, earlobe attachment, widow’s peak, Hitch-hiker’s thumb, Bent little finger and long palmar muscles pattern among Students of Dagmawi Berhan primary school in 2020/2021 academic year. Morphological traits of grade 7 and 8 students of both sexes who volunteered were taken from each participant after agreement or consent was obtained from the students and their respective parents, indicating their readiness to participate. Data collection for morphological traits was done utilizing an observation and recording technique. Figures, tables, and words were used to present the findings. In this study the frequency distribution of the curved widow’s peak was lower than straight hairlines among the population. There were also the more frequency distribution present long Palmaris muscle was found to be male 106 (36%) and lower distribution in female 83 (29%). The study showed that among the morphogenetic traits assessed with the selected population, a significant association was observed in morphogenetic traits of Widow’s peak; tongue rolling, Earlobe attachment and Palmaris longues muscle with sex in the selected population. Other morphogenetic traits which were bent little finger and hitchhiker thumbs did not show association with either of the sex in the study.
Genetic Diversity in Sorghum (Sorghum bicolor (L.) Moench) GermpJasm From Ethiopia and Eritrea.
(Addis Ababa University, 2001-06) Ayana, Amsalu; Bekele, Endashaw (Prof.)
Infonnation about the amount and distribution of genetic variation in gennplasm collections is important for efficient management of gennplasm collections and for effective utilization of such materials in plant breeding. Sorghum (Sorghum bie%r (L.) Moench) is one of the most important cereals worldwide and its tolerance to drought makes it particularly important in semiarid tropical regions, including Ethiopia and Eritrea. The significance of sorghum gennplasm from these countries for worldwide improvement of sorghum is also well acknowledged. However, there is limited infonnation about the amount and distribution of genetic variation in sorghum gennplasm from these countries. In this thesis, the amount and pattems of distribution of genetic variation was detennined in cultivated sorghum (s. bie%r ssp. bie%r) gennplasm collections from Ethiopia and Eritrea using morphological traits, allozymes and random amplified polymorphic DNA (RAPD) markers. A similar investigation was made on wild sorghum (s. bie%r ssp. vertieillijlorum) from Ethiopia using RAPD markers. The results show that the materials exhibit a wide range of variation for quantitative traits and a high Shannon-Weaver diversity index (il= 0.90) for 10 qualitative traits. In contrast, the level of allozyme variation was found to be low (mean expected heterozygosity = 0.024). The level of RAPD variation was found to be intermediate both in cultivated (il=0.53) and wild sorghum (H= 0.49). The lack of correspondence among the three levels of variation revealed by these methods points at the difficulty of making prediction of variation of one based on the other and explanations are provided for the possible causes of the disparity. Despite the disparity in the levels of variation from the three data sources (i.e. , morphological traits, allozymes and RAPD markers), the structure of the variation was fOlmd to be similar for all the data sources. In all, the within accessions, regions and the within adaptation zones variation accolmted for a large portion of the total variation compared with the between accessions, regions and the between adaptation zones variation. Based on these results, sampling more accessions within each regions and adaptation wnes and more individuals within populations are suggested as future sampling strategies. Grouping of the materials into lowland, intermediate and highland elevations seems to be justified only for discriminant analysis of quantitative traits, otherwise, there was no convincing evidence that such materials are genetically substructured. Regions with overall high diversity are identified and suggested for in situ conservation. The results from quantitative trails indicate that accessions from Eritrea could be important sources of genes for early maturity. Detailed implications of the results for germplasm conservation and utilization are discussed and future lines of research are suggested. Key words: alJozymes; genetic variation; germplasm; morphological variation; RAPD; Sorghum bicolor
Socio-Clinical Characteristics of Patients on Antiretroviral Treatment in Tulu Bolo South-Central Ethiopia from December 2008 to August 2019
(Addis Ababa University, 2021-09-23) Amano, Masino; Mamo, Hassen (PhD)
The discovery of antiretroviral treatment (ART) substantially reduced the burden of HIV/AIDS and improved the life quality of people living with HIV/AIDS (PLHIV). However, ART effectiveness is subject to various determinants, and regular monitoring of the clinic-characteristics data of attendants is recommended. This study was aimed at analyzing the socio-clinical characteristics of patients on ART at Tulu Bolo Health Center (TBHC) and Tulu Bolo General Hospital (TBGH) in Becho woreda district (south-central Ethiopia) from December 2008 to August 2019. Overall, 538 PLHIV (M=229, F=309) were registered during the last twelve-year at the ART center of both facilities .The retrospective data was collected by tally method from the ―voluntary counseling and Testing Registration Log Book‖ and from quarterly reporting formats of the health institution. The research sites were identified,Socio-clinical data were collected , measurements were made, and analysis of data was made. Heteromantic mode of transmission was the known way in the area and pulmonary tuberculosis was the most common opportunistic infection. Many of the participants (212(39.4%)) were 40 years and above. Overall, the data demonstrates age-dependent increase in the number of PLHIV in the facilities. The proportion of rural ART followers (265(49.3%)) was nearly the same as the urban residents (273(50.7%)). The number of underweight participants decreased from 62(11.0%) to 12(2.2%). The pooled viral load test results showed that 468(93.9%) out of the tested 498 was undetectable. In some few patients although the viral load was detectable, their health status was good. The number of participants having CD4 count below 350 before ART initiation was 358(66.5%) and this number substantially dropped to 54(10.1%) after ART initiation. Correspondingly, 502(92.5%) participants were in the WHO stage I, 26(5.7%) stage II and 10(1.8%) stage III. Majority of the participants (335(61.7%)) had a follow-up period of ≥4 years, 107(21.1%) 3 years, 55(9.9%) 2 years and 41(7.3%) 1 year. During the overall follow-up period, 50 died, 51 lost-to-follow-up and 43 were transferred. The highest number of PLHIV registered in TBGH was in 2017 and in TBHC in 2015. The data in the rest years were up and down with no clear pattern of gender-based distribution. ART adherence of 483(89.2%) participants was good and the clinical status of the participants was good. ART adherence of 483(89.2%) participants was good and the clinical status of the participants was good. Although the overall clinical characteristics of the patients was considered good because of good adherence, awareness creation and training more healthcare workers must be done to support especially those in the rural area.
Coffee Shade trees Current Status Phenology Management Practices and Threats in Kochere Woreda Gedeo Zone SNNPR Ethiopia
(Addis Ababa University, 2021-09-07) Agmas, Ahmed; Negash, Legesse (Professor)
This study was conducted in Kochere woreda,Gedeo Zone,SNNPR, Ethiopia. The aim of this study was to identify the most common and important shade tree species,current status, phenology and threats and to document farmer’s perspectives on the environmental and socio economic benefits of the shade trees on coffee production systems. The data were collected through structured and semi structured interview,questionnaire,and field observations. Data were analyzed using preference ranking following (Martin,1995),direct matrix ranking following (Cotton,1996) and appropriate percentage were used. Wherever descriptive statistics were also computed so as to summarize the essence of the data. Six most common coffee shade tree species were selected in the study area. Farmers preferred these shade tree species in their coffee plantation due to their shade providing and soil fertility improvement and also based on their multipurpose values. Coffees under shade increase the yield and size of coffee beans however under sun growing,cup quality and coffee bean size decrease. Agroforestry practice was takes place deliberately the production of woody and non woody crops in the same field of land. Removing of weed,inter cropping,protecting natural regeneration plants,looping of side branches as well as pollarding and debarking were constitute the major management practices. People highly exploited in the natural environment as the source of their lively hoods,it promote negative effects on plant distribution. Regarding to threats of coffee shade tree informants clearly put their worries about the future prospective of these shade trees under the existing dynamics .This research identifies that the rapid population growth in the study area as a potential threat to the sustainability of coffee shade tree.
Ethnobotanical Study of Medicinal Plants Used in Indigenous People in Lemo Woreda Hadiya Zone SNNPR Ethiopia
(Addis Ababa University, 2021-08-22) Abayneh, Iyasu; Lulekal, Ermias (PhD)
Medicinal plants have not been well studied, tested or documented in the study area. Most of the information is steel in the hands of the traditional healers. This study was carried out 25 February-March 20, 2018 to explore ethnobotanical information on the use medicinal plants in lemo district people in 12 kebeles. The ethnobotanical techniques used to collect and analyze data were: semi - structured interview, guided field walk and observation, group discussion, preference raking and paired comparison, direct matrix ranking, informants’ consensus factor and fidelity level combined with descriptive statistical analysis. Ninety informants (60 males and 30 females) from 12 kebeles were Included in the study. A total of 60 ethnomedicinal plant species belonging to 55genera and 34 families were collected, identified and documented in this study. Most commonly used plant families are Asteraceae followed by Lamiaceae. The highest informant consensus factor (0.83) was associated with problems caused by gastro-intestinal parasites. Dermal diseases (0.77), emergency diseases (0.70) and organ diseases (0.65) stood 1st2nd, 3rd and 4th respectively. Preference ranking, paired comparison, direct matrix ranking and fidelity level index showed the efficacy, popularity and preference people have for some species over the other for different uses and in treating ailments. Deforestation, land degradation, overgrazing, increasing of population number and fuel wood are the main threats of medicinal plants identified by informants of the study area.
Facility Based Retrospective Study on Malaria in Wondo Genet Sidama Regional State South Ethiopia
(Addis Ababa University, 2021-09-21) Lemma, Kassahun; Mamo, Hassen (PhD)
Currently, malaria is a widely prevalent and poses a serious challenge although elimination is the agenda. The main objective of the study was retrospective assessment of malaria in health-facilities of Wondo Genet district, Sidama Regional state, south Ethiopia. A retrospective design was employed in order to gather information. This was done by reviewing the past five-year (2015-2019) malaria morbidity records of the district. During this period a total of 15,218 thick and thin Giemsa stained blood films were examined and 3530 (23.20%) microscopically confirmed malaria cases were reported as a decreased inter-annual trend. Plasmodium vivax and plasmodium falciparum accounted for 50.9% and 49.1% of the cases respectively. Although malaria was reported in all age groups and both sexes, ≥15 year age group and males were more affected. However, the prevalence of malaria infection between males and females was not statistically significant (P>0.05) and, not among age groups. Despite the apparent seasonal fluctuation of malaria trends in the area, the peak of malaria cases was reported during June, August and September within the last five years. Although malaria was in a decreasing trend, it remained a significant public health threat in this particular area. Therefore, intervention measures need to be strengthened to effectively reduce the burden of malaria in Wondo Genet.
Use and Conservation Status of Native Treesand Shrubs in and Around Gondar City Amhara Regional State Ethiopia
(Addis Ababa University, 2021-09-16) Tassew, Enyish; Negash, Legesse (Professor)
Native trees and shrubs serve a wide range of uses within conventional farming system. The objective of this paper was to documne t uses and onsuservation status of native trees and shrubs in and around the city of Gondar. To this end, 136 respondents from two rural kebele and one urban kifle ketema randomly. For selection of the most preferred native tree species and shrubs 12 key informants were purposively selected based on their wisdom about trees and shrubs. Questionnaire containing together open-ended and structured questions were employed to collect data on use (or abuse) of selected native trees and shrubs. The data, collcted from 136 informants, were reviewed using the techniques of free-listing, preference ranking and direct matrix ranking. Verifying the preference ranking findings, direct matrix ranking also showed that Juniperus procera is the most exceedingly preferred tree based on multiple attributes. Key informants ranked it the first for its use in fencing and construction and a source of cash income. Accacia Abyssinica was also ranked as the highest of all as a source of fuel. Ricinus Communis was ranked higher than all other trees based on its growth performance. The most preferred native tree species (e.g. Olea europaea ssp.cappspodata and Juniperus procera) have become increasingly rare, as described in interviews. The ,pst highly listed uses was fencing and the lostes were beeforage and spiritual. Households have initiated planting a few native species. Immediate organized measures are crucial to avoid the rapid replacement of native woody plant diversity by a monoculture of non-native trees. A community-based platform for unified ecological renewal of native plant variety would necessitate assistance from local government organizations and non-governmental organizations.
Cytogenetic Study of Some Species of Swertia L. (Gentianaceae) from Ethiopia
(Addis Ababa,University, 2000-05) Kebede, Mulugeta; Dagne, Kifle (PhD)
Chromosome data have contributed little towards resolving the problems of classification and phylogeny orthe Swertia species (Y uan, 1993). For many species of the genus the chromosome number as weJ[ as morphology were not stud ied (Yuan and KUpfer, 1993). In the present work, ch romosome numbers were documented for six species of Swerlia L. (Gentianaceae) from Ethiopia. S. fimbria/a, s. kiJill/wu/s charica, S. macrosepa/a subsp. microsperma and S. va/kensii var. baleellsis were found to be diploid with 2n=26. S. crassillscula subsp. robllsta was dip loid with 211=20. The above chromosome numbers were determined from mitotic chromosomes. Diploid (211=20, n"" I 0) and tetraploid (2n=40, n=20) chromosome numbers were found for S. abyssillica from meiot ic chromosome study. The chromosome numbers of S. crassilisclila subsp. robusta , S macrosepala subsp. microsperma, S volkellsii val'. baleensis and 211=40 cytotype of S. abyssil/ica were reported for the first time. Further, the present study confimled previous reports on the chromosome numbers of the remaining species and the basic chromosome number x= 13 and x=1 0 for the genus. Karyotypes of five species of SlI'ertia namely, S fimbria/a , S. kilimalltischarica, S. macrosepala subsp. microsperma. S. crassiuscula subsp. robusta and S. volkensii val'. baleellsis have been described and their similarities and differences were discussed. Even though tile chromosome morphology of these species is very similar, some variat ions in basic number, ploidy level, satell ite number and size of chromosomes were observed among the Swerlia species studied. The study revealed that the spec ies were heterogeneous. It is recommended that fu rther study of karyotype of all the species of the genus including chromosome banding is necessary to complete the cytotaxonomic knowledge of the genus as a whole.
An Ecological Study of the Vegetation of Choke / Mountain, East Gojam, Ethiopia.
(Addis Ababa,University, 2000-06) Chimdessa, Meseret; Demissew, Sebsebe (Associate Professor)
Vegetation of Choke Mountain was studied. Vegetation data of sixty sample plots from five transects were taken from October to November 1999. These were subjected to cluster analysis by distance optimization. Five distinct clusters were obtained. Soil Samples were also collected and analyzed. Results of so il analyses and other environmental variables were compared among clusters. Total nitrogen, exchangeable potassium, percent particle fractions, altitude and slope showed significant difference among clusters. Based on the investigation, Recommendation towards the conservation of natural Vegetation of the area is also given .
Assessment of Intestinal Parasites in the Effluent Slurry of Toilet-Linked Biogas Digesters
(Addis Ababa, Ethiopia, 2006) Hailu, Tesfaye; Mekonnen, Yalemtsehay(PhD)
Five toilet-linked biogas digesters working with in the range of ambient temperature were assessed to detennine the presence of intestinal parasites in the effiuent slurry considering the four seasons. These were in Addis Ababa (at Asko, Lidcta and BisrateGebriel), at Fitche and Awassa. Retention days were dctcnnined through recording the flow rate of influent slunies. Eggs of intestinal parasites of the influent and effluent slurry from the di gesters were identified by taking samples when the influent channeled into the digester at the mixing pit and effiueDt slurry away through the reservoir for each season.
The Forest Patches of Gurage Mountains: Floristic Composition, Ecology and Anthropogenic Influences
(Addis Ababa, Ethiopia, 2013) Demsis, Tamru; Demissew, Sebsebe(Profasser)
Degradafion a/vegetation cover;s cOl/sidered as olle o/Ihe mOSI seriOIlS ellvironmellfal problems/acing Elhiopia and 'he world aI large. Studies revealed fliaf fhe vegc/a1ion resources of Ethiopia are disappearing much jasler lhon the efforts made 10 document Ihe informa/ioll and prOjXJse miligat;on programs. Hence, Ihe presen' sllIdy was conceived 10 investigate jlorislic composition, pal/ems of plam diSlribUlion. cl1vironmel1laf variables ,hal aCCOllnl for these palfems and 10 explore faclors 'hOf lead 10 foss offorest cover in Ihe Gurage MoulI/ains. Stralified pre/eremial sampling was used 10 col/ectjlorislic dtlfa. Plol size of 40 x 40 m was IIsed for vegclalion sampling. The altitude of each main plol was recorded /Ising Gal'lnill GPs. Soil samples were taken qt com ers oflhe 20 x 20 m subplols and composile samples were made. IntensilY of anll1ropogenic disluroonce in each plol wru estimated by considering Ihe following IXlrametel's: number of trees and shrubs c ut, [001 trails. seedlings Irampled as well as grazing/browsing inlensily. Focus group il1lerviell' was used 10 idelllify [actors that account for loss of vegetatioll cover in the study area. Data from cemral statistical agency of Ethiopia were used to supplementlhe data from the interview. Cluster analysis was used to idell/ify plalll community types ill the . study area. Canonical correspondence analysis was to investigate the I'elalion between environmental variablej' alld Ihe plant communities. 111 addition. ANOVA was IIsed to examine the relationship bel1l'een the plant communities and enviromllellfal variables. Generalized linear modeling was used 10 relate species ric/mess pal/ems q(llie Gurage Moulltains to the measured explwwlnry variables. A lolal of JJ9 plant species belonging to 89 families were encountered in the study area. Abollt 10 % of the plants were endemic 10 i:.ihiopia. Canonical correspondence analysis revealed lhat altitude, slope, disturbance, soil c/ay, sand and pH, had significant relmiol1 with Ille plam communities. Analysis of variance verified that a/litllde, slope. disturbance, soil pH. clay and sand cOlllem of Ihe soil were sigllijicamly relaled to the plam communities. Generalized linear modeling showed Ihat dislllrballce, aitilllcie, pH and slope were Ihe mOj'l importalll factors influencing the plant species richness paflern of Ihe Gurage Moul/tains. £rpallsiOll of agricultural land, population pressure, wood extractiOIl, institutional weaknesses and grazing were the main drivers fa/' forest loss and degradOlion ill the study area. Overall. the forest patches sllfdied are characterized by highflorislic diversity and house a good lIumber of endemic plal1ls. Immediate cOlls~rvalio" inten'entiOIl is recommellded for the recovely and sustainable lise of 'he remnant forest fX1tches.
They Population Status of African Elephant (Loxodonta africana, Blumenbach, 1797) in Chebera/ Churchura National Park, Ethiopia
(Addis Ababa, Ethiopia, 2006) Ademasu, Meseret; Mebrate, Asefa(PhD)
A study on the history and status of lhc population of African elephant (Loxodon/a a!riclllla) and human-elephant conflict in Chcbera-Churchura National Park was conducted from July 2005 to March 2006. TI1is study was aimed to fill infonnalion gap on the population status of the elephants of the south western mid-altitude fore st in the country. Data on the population history, seasonal movement and distribution and the human-elephant interactions in the area were collected based on the questionnaire survey and field observations. The population size ,and abundance of elephants in the area was detennined from dung counts survey. The dung density was detcnnined based on line transect survey and a total of 45 transects with a length of 68.3 km were surveyed within high and medium density strata. The age and sex structure of elephants were categorized based on the body size comparison, footprint measurements and bolus circumference measurements. The history of the elephant population of the area appeared to have started within the last three decades when it was seen for the first time in the area. The elephant population came to the area from the side of Omo National Park. The population has been increasing in size and extent of distribution since the late 1990s to cover the present study area and its surroundings. However, following an intensive poaching and habitat degradation due to human activities since the transitional government, they are confined to two localities in , CCNP. The elephant population has two groups locali zed in the northern and the western parts of the Park within 250 km2 area. The elephant popUlation has extended wet season home range that was detem1ined by habitat and human factors. The population size of the elephants was estimated to be 85 (± 24) with a density of 0.007 \\elephantslkm2. Defecation and dung decay rates were 16.57 (± 2.044) droppings/ elephant! day and 0.01 33 (± 0.001 7) droppings/day respectively. The elephant population was expressed as young and growing population, but with less number of juveniles and ca lves, might be due to mortality and/or reproductive pressure from elephant density or human factors. The more skewed sex ratio in favor of females (I :2) and less number of males above 20 years of age were probably due to selective poaching for adult males with relatively larger ''tusk. ix " The human clephant conflict was associated with the size and distribution of the elephant population, commonly distributed before onc and half decades ago. The impact of elephants on the surrou nding communities was local ized to four vill ages (20% of the boundary line). However, habitat loss and killing of elephants by human activities continued till the present. These findings of the study are important in making management decisions and are base lines for future monitoring of elephants of the area.
Ataxonomic Study of Blepharis Edulls(Forssk.) Pers. Complex (Acanthaceae)
(Addis Ababa,University, 2000-06) Malombe, Itambo; Kelbessa., Ensermu (PhD)
The species /3Iep/1oris eduJj~· (Forssk.) Pers. has jor long been miSlaken w;lh B. linariaejolia Pers. and B. cjfiari~' (L) B. L. Bun or IJ. boranensis Vollesen (ined.) alld most ojlhe colleclions identified indiscriminately. While revising Ihe genus. of/empl by Vollesen 10 separa/e (he species. Ihough wilh considerable observed morphological varitlliOn oj specimens, wasjillile and recommended on in ftC/specific sludy based on morphology. This sl/Idy, therejore, employs phenelic lechniques on gross morphology. bOlh mtllure and seedlings characlers in conjllncfion wilh palynological evidence to disenlangle 13. edl/lis complex and re/ated (axa. Clllster analysis segregatedjour groups. which were jimher verified by Principal Component AnalYSis. Discriminant Analysis and Non·Paramelrlc Analysis. Importantly, vegetative and floral characters discontinuollsly or panially separawd fhe accrlled ell/Sler groups. These results were jimher supported by IXilynology. Subsequently, rhese laxQ wac de~·r.:ribcd as B. boranem'ls Vollesen (ined). /J edulls var. edulis Pers .. B. edulis var. glabra Malombe var. nov. and B. edulis var. isabellae Malombe var. nov. The species B. boranensis, a pan jrom elmr separtllion in the ordination space. it is morphologically discrete from all the OIher qffilialed groups. /J edulis var. edulis is dislinguished discontinuously jrom B. edulis var. isabellae and panialiy from B. edlliis var. glabra by [etll llres of cOlyledoll colOllr. lIumber and arrangement of leaf marginal spines. More so. Ihe three varieties lack a wide geographical varitllion.
The in Vivo and in Vitro Nitrate Reductase Activity in Tef (Eragrostis Tef (Zucc.) Trotter under Different Assay Conditions
(Addis Ababa,University, 1982-06) Negash, Legesse
the presence , substrate ind cibility and regulatios of the enzyme ni trate reductase ( NADH : Nitrate Oxidored case , E . C. 1.6. 6.• )(NR) of b o h ark- grown and l igh - gro n tef plants ( Eragr osti s te f (Zucc . ) Trotter) were st died . The relat ive merits of the in vivo and i n vitr o methods of assay for t he en zyme we r e ev a l uated . Major fac ors affecting n i t r a e r educta se act ivit y and the distr ibution of the e zyme in both t h e dark- and light- grown plants wer e investigated .
Merphological and Molecular Diversity in the Ethiopi an lentil (Lensculinaris medikus) Landrace Accessions and their comparison with some Exotic Genotypes
(Addis Ababa, Ethiopia, 2006) Fikiru, Edossa
Seventy landracc accessions and eleven genotypes were used for morphological and ISSR diversity study. The plant materials were grown in a simple lattice design of two repl ications for morphological di vers ity s tudy at Sinana Agricult ural Research Center. Ten plants were selected randomly frolll each accession/genotype and marked before flowerin g. Morphological data were recorded from all selected plams on cleven trailS. DNA was ex tracted fro Ol a bulk sample of fi ve plants using a triple CTAB extraction technique. Molecular data were generated using lour ISSR primers. ANOVA of morphological data indicated significant differences among the pl ant materials. Estimmcs of phenotypic and genotypic coeffic ien ts o f vari ation showed wider variabili ty within and between the landrace popula tions and betwccn land races and exotic genotypes for different morphological characters. Morphological dissim ilarity between the populations ranged from 0.05 19 to 0.73. Clustering anal ysis based on morphologi cal di ssi milarity matrix re vealed three groups wi th distinctive morphological traits. The wider phenotypic variability observed encourages improvement acti vities between the lentils. Molecular analysis, on the other hand, showed that exotic genotypes were more diverse compared to the landraces. Genetic di versity with in the total landrace population (I-I r) was 0.1734. !-ligh AR-based genetic diversity (0. I 395 - 0.1039) was observed for samples from Gonder. Shewa and Well o. lI igh wi thin GR divers ity was obtained for samples from NEE and the least for those from SEE. Exotic genotypes were more di stantly related with samples frolll Tigray, Gojam and Shewa than to others. The genetic di stances between populations of Ethiopian lentil land races ran ged from 0.2284 - 0.0 12. Samples from CE were more distantly related to samples of SEE. while the di stance between other GRs was relatively low. Es till1 ates of population difTerent iat ion and gene now were moderately high ror ARs. On the other hand. GR-based population difTerentiation was low, whereas among GR gene flow was high relative to AR-based population di fferentiation. AMOVA revealed higher within population variation than among population. Cluster analysis based on Dice's s imilarity coefficient revealed three groups with di stinct molecular proliles both wi th and without exotic genotypes. There were high ly s ignificant (p < 0.00 1) corre lations, r = 0.45 and r = 0.26, between morphological and molecular distance matrices, respecti vely, of the entire pl ant materials and landraces separately. implying the vali dity or both methods for diversi ty study in lentil s. Observation of low \\ ith in ARlpopulation divers ity invi tes fu rther collection ac ti vities. while enriching populations with high genetic diversity.
Diversity of Sorghum (Sorghum bieolor (L.) Moench) in North Shewa and South Welo Region of Ethiopia: Focus on Farmers' Varieties with _ Emphasis on Frequency of Occurrence and Use Values in Relation to Morphological and Biochemical Characters
(2000) Abdi, Adugna; Bekele, Endashaw
Thirty four sorghum (S.bieolor (l).Moench) landraces consisting of 1020 indi vidual plants (30 plants of each land race) collected from five agroecosites in North Shewa and South Wela regions of Ethiopia (Bati 8, Fontenina 5, Hayike 2. Layignaw alaye 17, and Merewa Adere 2) were lIsed in this study. The materials were classified on the basis of administrational zones (4 cl ass ifying variables; Woredas, ecosite of origin and altitudes, Morphological variation for the fourteen quali tative characters that showed two or more phenotypic classes were estimated using the Shanon•Weaver diversity index (H'). Phenotypic variation was found between and within each classifying variable. The value of H' for ailiandraces varied from 0.32 to 0.98 with an overall mean of 0.77 ± 0.04. One way analysis of variance (ANOVA) showed significant differences between characters within all classifying variab les and this contributed to the largest portion of the total variance. Cluster analysis based on ordinal variables grouped the landraces in 5 clusters. A higher proportion of landraces sharing similar altitude groups and similar agroecological sites were grouped together. Panicle compactness and shape as well as stalk juiciness were the predominant characters in grouping the land races into th ei r respective cl uster. Panicle compactness and shape also contributed relatively more to altitudinal and ecological di ffe rentiation. This differential distribution of different panic le types with respect to compactness and shape revealed the adap tive significance o f panicle compactness and shape that re nected the patterns of di stribution of different races in north Shewa and south Welo regions. X2 test was carried out to detect the deviation of the observed rrequencyof all the characters from the expected ones. Significant dirferences were not observed for most or the characters between the observed and expected rrequenc ies. Isozyme analysis was perfomled usmg two-enzyme systems esterase (EST) and acid phosphatase (ACP) to see the allelic variation among the 34 sorghum landraces. However, phenotypic polymorphism was not observed for any of the enzymes used in the analysis. For the analysis of frequency of existence (diversity) of sorghum landraces under the environmental variability (altitudes and field size), transect method over 100 plots (fields) was used. As altitude levels increased or decreased beyond the range of 1500- 1650 m.a.s.l, the diversity of tile sorghum land races also decreased. A relatively lower field size located nearer to the home range was found to contain higher diversity. The use values of the 34 sorghum landraces were also analyzed by interviewing 30 informants in nonh Shewa and south Welo regions. Thirty informants were contacted and the uses of the identified sorghum landraces were recorded on 30 pl ots. Of atl the landraces zen gada and ahiyo comprised the maximum number of uses (15 and 13, respectively). However, almost alt-30 landraces were known to have been selec ted for their nutritional value as injera making and for their sui tability for beverage. Ethnobotanical survey was conducted and the important data on fann er perceptions about the agromorphologica! traits distinguishing land races. cultural val ucs and prefcrred traits of sorghum landraces were coll ected. The knowledge of farmers, which is documented in this study. is an important input to the build ing up of the scient ific basis of ill-sil/l conservation of agrobiodiversi ty in sorghum crops. The information retained from the famlers' knowledge can also be applied in future breeding activities and designingin-situ conservation program.
Juniperus Procera Hoechst. EX Endl.: Rooting of Branch Cuttings under a Low-cost Polypropagation System
(Addis Ababa,University, 2000-06) Assefa, Adane; Assefa, Adane (PhD)
The rooting responses of branch cullings obtained from class. Classll and class III stock plans of juniperus procera Hoechst. ex Endl. to indolebutytic acid (IBA) Were examined in sand rooting /media comtained in the comporments of a modified No special and complements.
Construction of Mycobacterial Expression Vectors
(Addis Ababa,University, 1999-06) Kidane, Dawit; Bekele., Endashaw (Associate Professor)
Molecular biology studies on M. feprae and M. tllberculosis involve cloning of genes and high level of expression to provide large amounts of protein. These proteins are used 10 study their usefulness in sub-unit vacci nes or as antigens in diagnostic kits. Most of the work that has been done to obtain protein antigens directly from the pathogens has drawbacks. For example the tedious purification methods and the inability to culture M.leprae in vitro. Most of these obstacles can be circumvented by over-expressing proteins in E.coli but that has its drawbacks as well. The posHransiationai modification in £.coli is absent or at least different from that m mycobacteria. Furthcnnore, some mycobacterial proteins can not be produced in E.coli. We have init iated studies to develop a mycobacterial expression vector th at might sidestep somc or the above namcd difficulties. This study describes the construction or a vector that allows the overexpression or mycobacterial proteins in a non-pathogenic, fast growing mycobacterial host. Firstly, we have cloned a number of model proteins in an E.coli expression system. These vectors allow the over-expression of M.leprae and M.lllberclIlosis recombinant proteins (45kD, Esat-6 and Trx) in E. coli. Secondly, a mycobacteri al expression vector (pDKl) was constructed. This vector has a hi stidine-tag that can be used for affinity purification or proteins. In this way we circumvent tedious biochemical purification systems. It also contains a multiple cloning site for convenient cloning of genes or interest. Thirdly, this pDK I expression vector was used to introduce the same test proteins as for the E.coli expression vector. These test proteins were over-expressed in E. coli as well as in a mycobacterial host. Both protein sets can be used to detcnnine whether there is any difference in recombinant prote ins obtained from E.coli and the semiautologous system using M. smegmaris as a recombinant host.
Ecosystem Services of Entoto Mountain Forest in Addis Ababa Ethiopia
(Addis Ababa University, 2021-11-09) Demessie, Habtamu; Soromessa, Teshome (Professor)
Addis Ababa is a highland city with varied topography and landscape features. The mountains that surround the city are covered with urban forest of different types. These forests are providing various ecosystem services for the urban and peri-urban population of the city. The value of this services is however poorly documented and less recognized by the relevant scientific studies. The objective of this study was to estimate the ecosystem service of the Entoto Mountain Forest (which is a principal forest reserves of the city of Addis Ababa) in terms carbon stock and sequestration weights and oxygen production rates. This was done through the use of forest inventory data collected from 46 sample plots (each with the size of 25 x 25 m (625m2) from Entoto Mountain Forest; and then estimating the biomass weight using on a combination of multispecies and species-specific biomass allomeric equations. The carbon sequestration and oxygen production rates were estimated through the use of mean annual tree growth rates and the corresponding biomass production rates estimates. The result shows that a total of 10,314 individual stands (which is equivalent to a density of 3,581 individual stands per hectare) were identified from the total sample plot area. The species diversity of the study area characterized by the domination of Eucalyptus globulus and Juniperus procera. The estimated amount of biomass and carbon stock weight is 1590.2 (552.3 t ha-1) and 744.7 t (258 t ha-1) respectively. The mean annual carbon sequestration and oxygen production rate is 23 t C y-1 ha-1 and 62 t O2 t y-1 ha-1. respectively. The estimated results and methodological approaches could be used as a measurement standard to determine the number of trees in an area required to maintain a healthy urban environment. The results are however a rough estimation and reaching to a more precise estimation requires continuous frost monitoring task with a focus on growth rate monitoring and biomass weigh estimation of different species.
Aerobic Heterotrophic Bacterial Flora of one of Shalla Hot Springs
(Addis Ababa,University, 1991-06) Kibret, Mulugeta; A. Gashe, Berhanu (PhD)
Four sites i n one ot the ho t.. springs ot Shalla were selec ted for the study. The wate r fr om t he sites me rge to form a s t ream whic h forms a te mperature gradient . In this study f our media we r e compa1;' ed tOI? the c ultivation and i solation o f aerobic heter otrophic bac ter i a. The pH of the ho t spring was 8. 7 with a temperature of 9G-56'C . The f o rmulated Illedia were adjusted to pH values o f 7 .0-13 .0. Howeve r , hlgh count s of bacte ria (lxlOl - 7x lOt c f u/ mll was only r egis tered when the pH was ad juste d be twee n 8.0 and 9.0. A medi um containing normal conce ntra tion of Trypton Soya Agar (TSA) was effective i n s uppo rt ing the growth of bacteria t han a med i um c on taining one quarte r strength of TSA o r supplement o f trace minerals. Replaci ng trac e minerals wi th hot s pri ng "" ate r improved the total numbe r of bacteria irowlng and also the number or i so l ates. Thcrmophl1ea were nume r o us (l:d Ol __ 1x l 0' clu/rol) than the rmo tol e r ants (2xlOl_2xl O( c fu/ml) at all sites . The population of Bac illus brevis , Bac illus spbae ricu8, Bacillus s t e arothermQphilu3 and Mi c r ococcus sp. was found to be low at l owe r e nvironmental temperatures than at hliher environmental temperatures . In t he course of t hi s s tudy a total of 44 micro organisms we r e isolated and char.cterlJ1ed. Twenty nine we r e identified to the s pecies level and were touftd to be membe r s o f genus Baci llus . Three isolates were Cram-positive cocci id e ntified t o the ge nus l eve l - Micrococcus. The r e main i ng 12 isolates were ei ther Gram-positi ve , filame ntous or no n- filamentous r od s wh ich need a deta il ed bioc he mi c al analysis for i denlifi c ation . To identify if any o f the isolates may have industrial applications , they we r e c hecked f o r product i on o f amylase and protease . Fifteen o f the isolates produced protease, 18 amylase and eleven I-roduced both amylase and protease.

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