College of Natural and Computational Sciences

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1,4-BENZOQUINONE MODIFIED CARBON PASTE ELECTRODE FOR VOLTAMMETRIC INVESTIGATIONOF DOPAMINE
(Hawassa University, 2025-04) KASSA BEKO
Dopamine (DA) is one of electrochemically active molecule; electrochemical techniques currently have received great interest for their investigation due to their simplicity, cost effective, low detection limit, and fast response time. This study investigates the electrochemical oxidation of dopamine using a low-cost and sensitive voltammetric method based on a 1,4-Benzoquinone modified carbon paste electrode. Cyclic voltammetry revealed significant enhancements in the oxidative peak current for dopamine at the modified electrode compared to unmodified carbon paste electrode, indicating its electrocatalytic properties. Scan rate, pH, differential pulse amplitude, and concentration of dopamine were optimized for the investigation of dopamine. The optimized values were 100 mV/s, 7, and 240mV, respectively. The voltammogram resulted from those parameters showed that quasireversible nature of the analyte towards modified electrode with the transfer of two electrons per molecule of the analyte. The dependence of anodic peak current on the square root of scan rate with high correlation coefficients (R2=0.99907 and scan rate (R2=0.99103) indicated that, the diffusion control is dominant, but adsorption also plays a role. Key kinetic parameters were calculated: anodic transfer coefficient (α =0.798), diffusion coefficient (D=2.18×10−7 cm2/s), and heterogeneous electron transfer rate constant (Ks,h=2.26×10−4 cm/s). Anodic transfer coefficient (α =0.798) value is closer to one this suggests that anodic process is more favorable. Optimization of experimental conditions led to be a linear response for DA concentration ranging from 1.0 × 10−3 M to 3.5 × 10−3 M, with a detection limit of 1.39 × 10−4 M using cyclic voltammetry and 7.64 × 10−5 M with differential pulse voltammetry. The result suggests that 1,4-BQMCPE is a promising electrode material for the development of electrochemical sensors for DA detection.
A COMPARATIVE ANALYSIS OF PHYSICOCHEMICAL PARAMETERS AND MINERAL CONTENT IN COW AND CAMEL MILK FROM AGA WAYU DISTRICT, GUJI ZONE, OROMIA, ETHIOPIA
(Hawassa University, 2024-06) DINAOL BAYU
This study aims to analyze and compare the physicochemical properties and mineral composition of cow’s and camel’s milk. Milk samples were collected from the Aga Wayu district in the Guji zone of the Oromia region, Ethiopia, using a proportional random sampling method. The physicochemical parameters analyzed included pH, titratable acidity, ash content, specific gravity, protein content, fat content, moisture content, total solids, and boiling point. Additionally, the concentrations of selected minerals (phosphorus, sodium, calcium, and potassium) were measured. The results showed that cow’s and camel’s milk exhibited similar physicochemical properties, with comparable pH (5.8 ± 0.5), titrateble acidity (0.20 ± 0.01), ash content (0.84 ± 0.12%), specific gravity (1.04 ± 0.11), protein content (3.32 ± 0.43%)for cow, fat content (3.6 ± 0.48%) and boiling point (92.66°C)for camel. The concentrations of sodium (3.63 ± 1.23 mg/L) and phosphorus (2.43 ± 0.39 mg/L) were also similar in both types of milk. However, cow’s milk had higher moisture content (85.13 ± 2.65%) and calcium levels (22.44 ± 2.41 mg/L) compared to camel’s milk, which had lower moisture (82.83 ± 1.22%) and calcium (17.07 ± 1.38 mg/L). Conversely, camel’s milk contained higher total solids (18.26 ± 0.50%) than cow’s milk (14.82 ± 2.11%). In conclusion, camel’s milk was found to have higher protein and lactose content than cows’s milk, while cow’s milk had a greater fat content. These findings highlight the distinct nutritional profiles of the two types of milk, which may have implications for their dietary applications.
ASESSMENT OF PHYSICO-CHEMICAL AND BACTERIOLOGICAL QUALITY OF DRINKING WATER SUPPLY, STATUS OF SANITATION AND HYGIENE PRACTICES: THE CASE OF BISHAAN GURRACHA TOWN, WEST ARSI ZONE, OROMIA REGIONAL STATE, ETHIOPIA.
(Hawassa University, 2024-05) MATIYAS AZAGE BETANE
Access to safe drinking water and adequate sanitation is essential for safeguarding public health. This study aimed to assess the physicochemical and bacteriological quality of drinking water supply and evaluate sanitation and hygiene practices in Bishaan Gurracha town, located in the West Arsi zone of the Oromia region, Ethiopia. The methodology involved selecting water sources and households for sample collection, employing data collection instruments including household surveys, key informant interviews, focus group discussions, and direct observations. Laboratory analyses were conducted to measure various physicochemical parameters such as pH, turbidity, TDS, EC, alkalinity, nitrates, chlorides, free chlorine, heavy metals, and bacteriological indicators including total coliforms and fecal coliform. Sanitation coverage and hygiene practices were assessed using appropriate questionnaires to ensure data suitability for statistical analyses. The results indicated that most physicochemical water quality parameters met the standard values recommended by WHO/ESA, except for temperature and turbidity. Temperature ranged from 24.33°C to 26.17°C, and turbidity ranged from 5.62 NTU to 6.73 NTU. Total coliforms were present in all water samples from source water and household storage containers, with a significant number of samples also testing positive for fecal coliforms. The mean total coliform counts varied between 18 CFU/100ml to 101 CFU/100ml for source water and 16 CFU/100ml to 81 CFU/100ml for household storage water. These findings suggest potential deterioration in the untreated drinking water distribution system within Bishaan Guracha town, as the total coliform and fecal coliform counts exceeded the recommended standards set by national and WHO guidelines. Inadequate sanitation facilities in many homes pose significant health risks to the community in Bishaan Guracha town. The absence of proper toilets and improved sanitation systems increases the likelihood of fecal contamination, leading to the transmission of waterborne diseases such as diarrhea, cholera, and typhoid fever. Immediate interventions are therefore necessary, including decontamination of water sources, repair of distribution lines, expansion of sanitation infrastructure, and increased awareness of hygiene practices. It is recommended to regularly monitor water quality and encourage community participation in sustainable water, sanitation, and hygiene services.
ASSESSMENT OF INTESTINAL PARASITIC INFECTION AND NUTRITIONAL STATUS ON UNDER-FIVE CHILDREN VISITING ASSELA REFERRAL HOSPITAL
(Hawassa University, 2024-05) TILAHUN ENDALE
Intestinal parasitic infections (IPIs) and undernutrition in under-five children are of significant public health concern in low- and middle-income countries and contribute significantly to childhood morbidity and disability. Unfortunately, under-five children are more susceptible to infection. However, information is scarce in the study area. Therefore, this study investigated the relationship between intestinal parasites and the anthropometric status of outpatients under five children in Assela referral hospital, east Arsi zone, Ethiopia. An institutional-based cross sectional study was conducted at Assela referral hospital from February 15 to March 15, 2024. Stool samples were collected from 227 children and examined using direct wet mount and formal ether concentration techniques. Children's weight, height, and Z scores were measured using a digital balance scale and a wooden board, with mothers or caregivers deducted from weight. The data were entered into Excel and analyzed using WHO-Anthro Plus software version v3.2.2 and SPSS v24 statistical software, respectively. An AOR analysis was done to test the association between intestinal parasites and nutritional status. The prevalence of stunting, underweight, and wasting was 38 (16.7%), 64 (28.2%), and 59 (26%), respectively. The total prevalence of parasitosis was 19.4% of children infected with at least one type of intestinal parasite. The most common intestinal parasitic infections detected in the study were E. histolytica (8.4%), E.Vermicularis (4.4%), and Giardia lamblia (3.5%). Residence (P: <0.001), deworming (P: 0.009), toilet (P: 0.034), and others like: fingernail cleanness, water source and parental education levels were the predictor variables for the prevalence of IPIs. Protozoan parasites are the most common cause of disease in under-five children in the area. Public health interventions for intestinal parasitic infections include targeted deworming programs, health education campaigns, sanitation improvements, routine screening, nutritional support, community-based interventions, and comprehensive health policies.
ASSESSMENT ON COMMUNITY AWARENESS AND PRACTICES TO INDOOR AIR POLLUTION IN JIMMA TOWN AND SURROUNDING RURAL KEBELES, OROMMIA REGIONAL STATE, ETHIOPIA
(Hawassa University, 2024-11) HARUNE ABAFOGI
Most households in Africa including Ethiopia still use biomass fuel to cooking their food and for heating in poorly ventilated houses. Indoor air pollution (IAP) is the presence of one or more contaminants in the indoor environment that has a degree of human health risk. The main objective of this study was to investigate community perception and level of community awareness towards IAP in Jimma town and surrounding rural kebele. Cross-sectional research design was used to achieve the study. Structured questionnaires, FGD and household observation were used as the data collection tools. Representative samples 360 households were included by systematic random sampling. Data were analyzed by SPSS both bivariate correlation and logistic regression was applied for the statistical test. The results majority of respondents (74.45%) the main source of energy for cooking was fire wood (88.6%) and charcoal (74.4), traditional type of stoves was made of cooking by majority (88.6%), in average (71.9%) respondents were aware of the source of IAP, most of (72.5%)household the two social groups were aware of the route of exposure and effects of IAP, largely (84.4%) respondents knew that exposure to IAP can affect human health and cause diseases, and lastly average (57.9%) of respondents knew that to reduce and prevent IAP. Majority (98.6%) of the respondents thinks that using cooking fuel that emits less smoke could prevent IAP. Other preventive mechanisms reported include: prohibiting cigarette smoking in living houses (98.0%), cooking always outside living houses (94.6%), avoiding living with domestic animals (95.2%) and keeping windows/doors open most of the time (91.2%). The households in this study had (71.9%) good awareness about the source of IAP, adverse health effects of IAP exposure and preventing measures of these adverse health effects, however, (84.4%) majority of them were still living with the risk factors associated with IAP in their daily living. There is need to provide education/awareness creation regarding air quality and its effects on health would be important and this can be implemented through community-based organizations that have wide acceptance in the study communities.
ASSESSMENTS OF HOSPITAL SOLID WASTE MANAGEMENT: THE CASE OF SAINT PAULS MILLENNIUM MEDICAL COLLEGE’S HOSPITAL AND GIRUM HOSPITAL, ADDIS ABABA, ETHIOPIA
(Hawassa University, 2024-05) FEKEDE GELETA HORA
With an emphasis on the potential threats hospital solid waste poses to healthcare personnel, the public, and the environment if improperly managed, the study assessed the solid waste management practices at St. Paul's Millennium Medical College and Girum Hospital in Addis Ababa, Ethiopia. The study's objectives were to characterize the types, determine the generation rates, assess the KAP of the hospitals administrative and health care workers, and investigate the challenges and opportunities in hospital solid waste management’s of the study Hospitals. A cross-sectional study was undertaken to assess HCW management methods and generation rate using direct observation, interviews, questionnaire surveys, and weighing scales, with data analyzed using SPSS 22. The Government Hospital (St. Pauli's) generated 882.30±49.54 kg/day of total solid waste, with an average of 1.757 kg/patient/day (1.6 kg bed day‒1 and 0.157 kg/outpatient/day) of 61.25% being classified as hazardous waste, and the remaining 38.75% being general waste. The private hospital (Girum) produced 124.81±65.24 kg/day of total solid waste, with an average of 2.12 kg/patient/day (1.8 kg bed‒1day-1 and 0.32 kg/outpatient/day) of 57.05% being classified as hazardous waste, while the remainder, 42.795%, was general waste. High hazardous waste generation rates exceed the WHO's 10–25% estimate, primarily due to inadequate waste source segregation. The Kruskal-Wallis test showed significant differences in waste generation rates between hospitals for all the HCW categories (P < 0.05). However, no significant difference was found in the mean generation rate of the HCW within the government hospital wards as well as within the private hospital wards (P˃ 0.05). Ward chiefs, medical directors, and department heads all have high KAP scores; however, "hospital administrators have a medium, and waste handlers have a low." The KAP scores of the private hospital outperformed that of the government. St. Paul's intermediate storage area converts all forms of waste (excluding sharp waste) into hazardous waste. St. Paul's inadequate placenta disposal, as well as Girum Hospital's feeding all types of produced trash into a low-combustion incinerator, may have endangered both the population and the environment. Inefficient waste management is caused by a lack of legislation and failure to follow guidelines.
ASSESSMENTS OF HOSPITAL SOLID WASTE MANAGEMENT: THE CASE OF SAINT PAULS MILLENNIUM MEDICAL COLLEGE’S HOSPITAL AND GIRUM HOSPITAL, ADDIS ABABA, ETHIOPIA
(Hawassa University, 2024-05) FEKEDE GELETA HORA
With an emphasis on the potential threats hospital solid waste poses to healthcare personnel, the public, and the environment if improperly managed, the study assessed the solid waste management practices at St. Paul's Millennium Medical College and Girum Hospital in Addis Ababa, Ethiopia. The study's objectives were to characterize the types, determine the generation rates, assess the KAP of the hospitals administrative and health care workers, and investigate the challenges and opportunities in hospital solid waste management’s of the study Hospitals. A cross-sectional study was undertaken to assess HCW management methods and generation rate using direct observation, interviews, questionnaire surveys, and weighing scales, with data analyzed using SPSS 22. The Government Hospital (St. Pauli's) generated 882.30±49.54 kg/day of total solid waste, with an average of 1.757 kg/patient/day (1.6 kg bed day‒1 and 0.157 kg/outpatient/day) of 61.25% being classified as hazardous waste, and the remaining 38.75% being general waste. The private hospital (Girum) produced 124.81±65.24 kg/day of total solid waste, with an average of 2.12 kg/patient/day (1.8 kg bed‒1day-1 and 0.32 kg/outpatient/day) of 57.05% being classified as hazardous waste, while the remainder, 42.795%, was general waste. High hazardous waste generation rates exceed the WHO's 10–25% estimate, primarily due to inadequate waste source segregation. The Kruskal-Wallis test showed significant differences in waste generation rates between hospitals for all the HCW categories (P < 0.05). However, no significant difference was found in the mean generation rate of the HCW within the government hospital wards as well as within the private hospital wards (P˃ 0.05). Ward chiefs, medical directors, and department heads all have high KAP scores; however, "hospital administrators have a medium, and waste handlers have a low." The KAP scores of the private hospital outperformed that of the government. St. Paul's intermediate storage area converts all forms of waste (excluding sharp waste) into hazardous waste. St. Paul's inadequate placenta disposal, as well as Girum Hospital's feeding all types of produced trash into a low-combustion incinerator, may have endangered both the population and the environment. Inefficient waste management is caused by a lack of legislation and failure to follow guidelines.
Characterization, Symbiotic Effectiveness and Host range of Alfalfa Nodulating Rhizobia Isolated from Soils of Selected Kebele‘s in Hawella District, Sidama Regional State, Ethiopia.
(Hawassa University, 2024-09) Bunamo Mitiku
Feed shortage, low quality and seasonal fluctuations have constrained livestock production in Ethiopia. Using high-yielding, good quality and drought-tolerant forage legumes like alfalfa (Medicago sativa L.) has been suggested to overcome the feed constraints. Alfalfa is an important forage crop, which forms a symbiotic relationship with nodule-forming bacteria Sinorhizobum meliloti. The aim of this study was to characterize and evaluate the symbiotic effectiveness and host range of rhizobia isolated from smallholder farmers’ fields in Hawella District, Sidama Regional State of Ethiopia using Alfalfa as a trap plant. To this end, a total of 12 bacterial isolates were trapped from different soil samples. The isolates showed differences in various presumptive, cultural, biochemical characteristics and physiological tolerances. Six (50 %) of the isolates( ANR 9, ANR 8, ANR 2, ANR 1, ANR 5 and ANR 11) could nodulate alfalfa with significant difference (P<0.05) in their capacity to infect and effectively fix nitrogen as evidenced from variations in nodulation parameters, shoot dry weights and shoot length. Accordingly, the isolates induced nodulation with nodule number ranging from 25.67 (ANR 9) to 9.00 (ANR 11) nodule per plant; nodule dry weight of 0.07 mg per plant (ANR 9) to 0.03 mg per plant (ANR 11); shoot dry weight ranging between 0.96 (ANR 9) and 0.17 (ANR 4) mg per plant and shoot length ranging from 30.50 (ANR 9) cm -11.47 (ANR 4) cm per plant. Using shoot dry weight as an indicator of the relative effectiveness, it was found that 33.3% of the isolates were highly effective (SE > 85 %) and 8.3 % were effective (SE ranging from 55 to 85 %) on alfalfa. Furthermore, the isolates showed broad host ranges on three legume species, namely, faba bean (Vicia faba), common bean (Phaseolus vulgaris), and lentil (Lens culinaris). All the six isolates (100 %) formed nodules with effective nitrogen fixation in faba bean, common bean and lentils exhibiting varying levels of effectiveness. Five of the six rhizobial isolates, ANR 9, ANR 8, ANR 2, ANR 1 and ANR 5 exhibited high N2-fixation efficiency and are recommended for further evaluation to use them as inoculants for different legumes. We also recommend these isolates for molecular characterization to determine their phylogeny and taxonomic classes.
Characterization, Symbiotic Effectiveness and Host range of Alfalfa Nodulating Rhizobia Isolated from Soils of Selected Kebele‘s in Hawella District, Sidama Regional State, Ethiopia.
(Hawassa University, 2024-06) Bunamo Mitiku
Feed shortage, low quality and seasonal fluctuations have constrained livestock production in Ethiopia. Using high-yielding, good quality and drought-tolerant forage legumes like alfalfa (Medicago sativa L.) has been suggested to overcome the feed constraints. Alfalfa is an important forage crop, which forms a symbiotic relationship with nodule-forming bacteria Sinorhizobum meliloti. The aim of this study was to characterize and evaluate the symbiotic effectiveness and host range of rhizobia isolated from smallholder farmers’ fields in Hawella District, Sidama Regional State of Ethiopia using Alfalfa as a trap plant. To this end, a total of 12 bacterial isolates were trapped from different soil samples. The isolates showed differences in various presumptive, cultural, biochemical characteristics and physiological tolerances. Six (50 %) of the isolates( ANR 9, ANR 8, ANR 2, ANR 1, ANR 5 and ANR 11) could nodulate alfalfa with significant difference (P<0.05) in their capacity to infect and effectively fix nitrogen as evidenced from variations in nodulation parameters, shoot dry weights and shoot length. Accordingly, the isolates induced nodulation with nodule number ranging from 25.67 (ANR 9) to 9.00 (ANR 11) nodule per plant; nodule dry weight of 0.07 mg per plant (ANR 9) to 0.03 mg per plant (ANR 11); shoot dry weight ranging between 0.96 (ANR 9) and 0.17 (ANR 4) mg per plant and shoot length ranging from 30.50 (ANR 9) cm -11.47 (ANR 4) cm per plant. Using shoot dry weight as an indicator of the relative effectiveness, it was found that 33.3% of the isolates were highly effective (SE > 85 %) and 8.3 % were effective (SE ranging from 55 to 85 %) on alfalfa. Furthermore, the isolates showed broad host ranges on three legume species, namely, faba bean (Vicia faba), common bean (Phaseolus vulgaris), and lentil (Lens culinaris). All the six isolates (100 %) formed nodules with effective nitrogen fixation in faba bean, common bean and lentils exhibiting varying levels of effectiveness. Five of the six rhizobial isolates, ANR 9, ANR 8, ANR 2, ANR 1 and ANR 5 exhibited high N2-fixation efficiency and are recommended for further evaluation to use them as inoculants for different legumes. We also recommend these isolates for molecular characterization to determine their phylogeny and taxonomic classes.
DESIGN AND SYNTHESIS OF SOME NOVEL HYBRID MOLECULES CONTAINING INDOLE AND OXADIAZOLE RING FOR EVALUATION OF ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES
(Hawassa University, 2024-06) AMANUEL ABRIHAM BUDE
Indole-containing oxadiazole compounds have emerged as a versatile class of nitrogen containing heterocyclic compounds with a wide range of biological activities. These compounds and their derivatives exhibit a diverse array of properties such as antiviral, anticancer, anti-HIV, antioxidant, antimicrobial, antidiabetic, and antimalarial activities. The aim of the study was to design and synthesize some novel hybrid molecules containing an indole and oxadiazole rings, followed by partial characterization of the synthesized compounds using UV-vis and FT-IR spectroscopic techniques, and assessment of their antibacterial and antioxidant activities. The synthetic methodology was initiated by esterification of 2-(1H-indol-3-yl) acetic acid (105aʹ) and 4-(1H-indol-3-yl) butanoic acid (105bʹ) using a catalytic amount of sulfuric acid and excess methanol. This process resulted in the formation of methyl 2-(1H-indol-3-yl)acetate (106aʹ) and methyl 4-(1H-indole-3-yl)butanoate (106bʹ) respectively. These esters were further converted to 2-(1H-indol-3-yl)acetohydrazide (107aʹ) and 4-(1H-indole-3-yl)butaneydrazide (107bʹ) respectively. Finally, the compounds (107aʹ) and (107bʹ) underwent a reaction with substituted carboxylic acids in the presence of POCl3 to produce the desired targeted compounds: 110aʹ, 111aʹ, 110bʹ, and 111bʹ. The synthesized compound yields were as follows: 110aʹ (62%), 111aʹ (55%), 110bʹ (57%), and 111bʹ (53%). The chemical structures of these synthesized compounds were partially characterized by using spectroscopic techniques like UV-Vis and FT-IR. The synthesized compounds were evaluated for their in vitro antibacterial activity test against four bacterial strains: E. coli, P. aeruginosa, S. pyogenes and S. aureus by the disk diffusion method. Among synthesized compounds, compound 111bʹ showed potent inhibitory activity against Gram-negative, E. coli with 11.57 ± 0.15 mm zone of inhibition compared to the standard drug tetracycline (13 ± 0.5 mm) at 150 mg/mL. The RSA of synthesized compounds were assessed through DPPH radical assay, revealing that compounds 111aʹ and 110aʹ demonstrated higher %RSA (91.83% and 89.9%, respectively) with IC50 values of 4.95 and 5.03, respectively, compared to the standard ascorbic acid of %RSA (87.5%) with an IC50 of 31.44 and than other synthesized compounds. Hence, the studies have indicated that all the synthesized compounds could be considered as potential candidates for further investigation in antibacterial and antioxidant research.
ECOLOGICAL AND HUMAN HEALTH RISK ASSESSMENTS BASED ON HEAVY METAL AND PESTICIDE RESIDUES IN SOIL AND VEGETABLES AROUND LAKE ZIWAY, ETHIOPIA
(Hawassa University, 2024-09) ASRAT FEKADU DEMSIE
The excessive use of pesticides can lead to harmful residues accumulating in vegetables, posing risks to human health. Therefore, regular monitoring and assessment of these potential health hazards are crucial. This study utilized the QuEChERS extraction method to analyze 15 composite samples (vegetables and soil). It employed an inductively coupled plasma optical emission spectrometer (ICP-OES) to detect heavy metal contamination in 18 composite samples of vegetables and soil. The findings revealed that some pesticide residues exceeded safety limits in tomatoes and onions. In tomatoes, α-endosulfan (0.58 mg/kg), β-BHC (beta-benzene hexachloride) (0.04 mg/kg), heptachlor (0.02 mg/kg), and Malathion (0.03 mg/kg) surpassed safety limits. Similarly, the average concentrations of heptachlor epoxide (0.04 mg/kg) and propargite (0.11 mg/kg) exceeded safety limits for onions. The study also evaluated potential health risks for adults and children, identifying both carcinogenic and non-carcinogenic risks. Non-carcinogenic health risk estimates indicated that onion heptachlor epoxide posed a systemic health risk for adult and child consumers with THQ (Target hazard quetient) > 1. Carcinogenic health risks (CHRs) revealed that heptachlor epoxide was present in levels exceeding acceptable limits (10–4) for both adults and children, while the CHRs of tomatoes and onions surpassed acceptable limits only for children. Additionally, heavy metal contamination of vegetables presents a significant concern, especially in areas with prolonged irrigation. The excessive use of agrochemicals particularly impacts the central region of the Rift Valley in Ethiopia. In a study of a soil-vegetable system irrigated by Lake Ziway in Ethiopia, researchers analyzed the levels of nine heavy metals (As, Cd, Cr, Co, Cu, Hg, Ni, Pb, and Zn). The analysis revealed that the concentrations of lead (Pb), arsenic (As), mercury (Hg), and chromium (Cr) in all tomato and onion samples exceeded the thresholds set by the FAO/WHO. In addition, the average ix concentrations of Zn, Pb, Cd, and Hg in all soil samples under tomato and onion plants were found to be above the recommended levels. This poses significant health risks, including systemic and cancerous effects. Moreover, traditional farming methods in the region were found to pose a high ecological risk to non-target soil species due to the use of common pesticides. The study aimed to assess the ecological risks that pesticides could pose to soil biotas, such as earthworms, springtails, and nitrogen mineralization organisms. The evaluation was based on the use of toxicity exposure ratios (TERs) and risk quotient (RQ) methodologies to determine general and worst-case scenarios, respectively. Of the detected pesticides, α-BHC, heptachlor, fenthion, parathion, and propoxur were detected at a rate of 100%. The highest concentration of 119.9 μg/kg was found for p,p'-DDE. Fenthion and Chlorpyrifos methyl posed a chronic exposure risk to F. candida (TERmax=0.86) and N mineralization organisms (TERmax=1.2), respectively. Non-target soil species are at high ecological risk (RQs > 1) due to Alpha endosulfan, which contributes to more than 90% of the risk than the other pesticides. The ecological risk assessment (ERA) reported that the overall pesticide mixture in soil poses a high ecological risk ∑RQ=5.3 in both scenarios. Conventional farming practices in the study area put soil organisms at risk. Therefore, it is crucial to establish effective monitoring protocols and raise awareness among stakeholders to ensure the preservation of the environment and the population's well-being. Furthermore, replacing harmful pesticides with low-risk alternatives is recommended to mitigate these risks. Urgent policies for awareness and surveillance are necessary to protect public health within and beyond the research field.
ETHNOBOTANICAL STUDY OF MEDICINAL PLANTS USED TO TREAT HUMAN AND LIVESTOCK AILMENTS IN DAWRO ZONE, SOUTH WEST ETHIOPIA PEOPLE REGIONAL STATE
(Hawassa University, 2024-06) TEMESGEN SHIFERAW
This ethnobotanical study was carried out to investigate and document the use of medicinal plants in Kechi woreda. In this study, 18 purposively selected key informants and 84 randomly selected general informants from three sampled kebeles were involved. Data were collected using semi-structured interview, group discussion and field observation. The collected data were analyzed using preference ranking, paired comparison, direct matrix ranking, informant consensus factor, jaccard’s coefficient of similarity and fidelity level index. A total of 91 medicinal plant species were identified. These species distributed under 81 genera and 42 families. Out of the identified medicinal plants species 75 species (56.81%) were used against human ailments, 40 species (30.30%) were used against livestock ailments and 17 species (12.87%) were used to treat both human and livestock ailments. Herbs constituted the largest growth habit (49 species) followed by trees (41 species). The most frequently used plant parts were leaves (46.07%) followed by roots (26.47%) and most widely used method of preparation was pounding (46.07%) followed by concoction (26.47%). The most common route of administration was oral (85.29%) followed by dermal (7.84%). Croton macrostachyus was predominant medicinal plant cited by most of the informants (53%) while the disease categories with the highest ICF value (21.33%) for abdominal pain. There was high preference for Ruta chalepensis for treating abdominal pain while paired comparison showed Phytolacca dodecandra the most preferred species for treatment of hepatitis illness. Anthropogenic factors such as agricultural expansion, firewood gathering, charcoal production, overgrazing etc. are the major threats to medicinal plants. In general, medicinal plants are still playing a significant role in the management of various human and livestock diseases in the study area.
GROWTH RESPONSES OF TOMATO (SOLANUM LYCOPERSICUM L.) TO INOCULATION OF ARBUSCULAR MYCORRHIZAL FUNGI AND TRICHODERMA HARZIANUM AND APPLICATIONS OF BIOCHAR AND COMPOST IN THE PRESENCE OF FUSARIUM OXYSPORUM FORMAE SPECIALES LYCOPERSICI UNDER GREEN HOUSE, HAWASSA UNIVERSITY, ETHIOPIA
(Hawassa University, 2024-05) BELETECH HABTE AWANO
Tomatoes (Solanun lycopersicum) are one of the most widely cultivated vegetable crops in Ethiopia. Tomato yields in smallholder cropping systems are below the potential of the crop, due to pests and diseases. Therefore, the objective of this research is to study the effect of inoculation of Arbuscular mycorrhizal fungi (AMF) and Trichoderma harzianum and compost and biochar amendments on tomato biomass, fruit yield and control of Fusarium oxysporum f. sp. lycopersici pathogen under Hawassa University greenhouse. The plants were grown in plastic pots filled with sterilized soils, arranged in a fourteen treatments including the control. A completely randomized design was used and growth measurements and disease severity assessment were taken after 15, 30, and 45 days of transplantation for all growth parameters including fruit yield and effect of the pathogen were measured. During early days of growth for treatments AMF+Fusarium and AMF+Trichoderam was recorded the highest height, leaf area and stem collar diameter for Galilea variety and variable values for ROMA V.F.N variety. When compared to plants treated with F.oxysporum f.sp.l alone and control, improvement in the various growth parameters was recorded in the plants treated with AMF, T. harzianum, biochar, and compost sole and combined. Better fruit yield and pathogen resistance was recorded for Roma variety. In addition to growth parameters all AMF inoculated treatments demonstrated root colonization, and sporulated. Nutrient uptake was enhanced in all treatments except for sole Fusarium and control treatments. Mycorrhizal dependency was better for sole AMF inoculation treatment in both varieties. Disease severity was lower in ROMA variety while Galilea variety was found to be more susceptible to Fusarium pathogen. Accordingly, significant fruit loss was recorded for Galilea variety. AMF and Trichoderma inoculation and application of biochar and compost has improved performance of the two tomato varieties. In addition, it was recorded that ROMA variety is much more resistant to Fusarium pathogen as inoculated with the two bio inoculants, which indicates that different varieties show different resistance to Fusarium pathogen. Therefore, when growing tomato it is recommended to select the appropriate bio pesticides like that of AMF and T. harzianum and appropriate variety of tomatoes. Finally, as this study focused on only two tomato varieties and two bio-inoculants, wide coverage of other bacterial and fungal inoculants production and application in the small holder farms is also recommended.
GROWTH RESPONSES OF TOMATO (SOLANUM LYCOPERSICUM L.) TO INOCULATION OF ARBUSCULAR MYCORRHIZAL FUNGI AND TRICHODERMA HARZIANUM AND APPLICATIONS OF BIOCHAR AND COMPOST IN THE PRESENCE OF FUSARIUM OXYSPORUM FORMAE SPECIALES LYCOPERSICI UNDER GREEN HOUSE, HAWASSA UNIVERSITY, ETHIOPIA
(Hawassa University, 2024-03) BELETECH HABTE AWANO
Tomatoes (Solanun lycopersicum) are one of the most widely cultivated vegetable crops in Ethiopia. Tomato yields in smallholder cropping systems are below the potential of the crop, due to pests and diseases. Therefore, the objective of this research is to study the effect of inoculation of Arbuscular mycorrhizal fungi (AMF) and Trichoderma harzianum and compost and biochar amendments on tomato biomass, fruit yield and control of Fusarium oxysporum f. sp. lycopersici pathogen under Hawassa University greenhouse. The plants were grown in plastic pots filled with sterilized soils, arranged in a fourteen treatments including the control. A completely randomized design was used and growth measurements and disease severity assessment were taken after 15, 30, and 45 days of transplantation for all growth parameters including fruit yield and effect of the pathogen were measured. During early days of growth for treatments AMF+Fusarium and AMF+Trichoderam was recorded the highest height, leaf area and stem collar diameter for Galilea variety and variable values for ROMA V.F.N variety. When compared to plants treated with F.oxysporum f.sp.l alone and control, improvement in the various growth parameters was recorded in the plants treated with AMF, T. harzianum, biochar, and compost sole and combined. Better fruit yield and pathogen resistance was recorded for Roma variety. In addition to growth parameters all AMF inoculated treatments demonstrated root colonization, and sporulated. Nutrient uptake was enhanced in all treatments except for sole Fusarium and control treatments. Mycorrhizal dependency was better for sole AMF inoculation treatment in both varieties. Disease severity was lower in ROMA variety while Galilea variety was found to be more susceptible to Fusarium pathogen. Accordingly, significant fruit loss was recorded for Galilea variety. AMF and Trichoderma inoculation and application of biochar and compost has improved performance of the two tomato varieties. In addition, it was recorded that ROMA variety is much more resistant to Fusarium pathogen as inoculated with the two bio inoculants, which indicates that different varieties show different resistance to Fusarium pathogen. Therefore, when growing tomato it is recommended to select the appropriate bio pesticides like that of AMF and T. harzianum and appropriate variety of tomatoes. Finally, as this study focused on only two tomato varieties and two bio-inoculants, wide coverage of other bacterial and fungal inoculants production and application in the small holder farms is also recommended.
HABITAT CHARACTERIZATION AND INSECTICIDE RESISTANT STATUS OF ANOPHELES GAMBIAE (S.L.) IN MALARIA ENDEMIC DISTRICTS OF SIDAMA REGION, SOUTH ETHIOPIA
(Hawassa University, 2024-05) MEDAN TAYE HUSSE
The prevalence of malaria in Ethiopia has decreased somewhat in recent decades, but it is currently increasing as a result of the introduction of insecticide-resistant Anopheles mosquitoes. Therefore, the purpose of this study was to assess the anopheles mosquito's insecticide susceptibility status and habitat characterization in a selected study area at November. Cross sectional study was used to conduct the study. The presence of Anopheles larvae was confirmed in all water-holding habitats, and information about the habitat's perimeter, water depth, light intensity, current flow, temperature, pH, turbidity, and proximity to the closest house was noted. Additionally, information about vegetation coverage, permanence, surface debris, emergent plant, habitats and substrate type of larval holding habitats were recorded for the purpose of characterizing the habitat. Sample of anopheles larvae were taken to Akililu Lemma Institute of Pathobiology from study area in November 2024. The larvae were then reared there, their insecticide susceptibility tested, and their species was identified using the Coetzee 2020 identification key. In order to test for insecticide susceptibility, 100 adult Anopheles mosquitoes were exposed to each insecticide that the World Health Organization (WHO) recommended (propoxur 0.1%, deltamethrin 0.05%, and alpha-cypermethrin 0.45%). The knockdown times (KDT), percentage knockdown, and percentage mortalities of the exposed mosquitoes were noted. Anopheles gambiae s.l., the species of mosquito that was identified, was resistant to propoxur (0.1%) and delthametrin (0.05%), but it was completely susceptible to alpha cypermethrin (0.45%) across all study sites. In all research sites, alpha-cypermethrin insecticide took less time (18.67-24.23min) to kill 50% of Anopheles gambiae s.l. In every study area, the KDT50 of Anopheles gambiae exposed to propoxur insecticide was high, ranging from 51.95 to 56.25 minutes. Anopheles mosquito species that dominate study area was Anopheles gambiae s.l; it was susceptible to Alpha cypermethrin and resistant to delthametrin and propoxur and it prefer to breed in habitat which exposed to sun light, had stone substrate and had no canopy cover. Anopheles gambiae (s.l) that inhabit Chuko, Dale and Loka Abaya was susceptible to Alphacypermethrin and resistant to Deltamethring & Propoxure. This species was highly productive in habitat like ditches, burrow pits and road puddle which exposed to sun light, without canopy cover and with stony substrate.
IMPACT OF LAND USE TYPE ON THE DIVERSTY AND ABUNDANCE OF ARBUSCULAR MYCORRHIZAL FUNGI IN LOKA ABYA, SIDAMA REGIONAL STATE, ETHIOPIA
(Hawassa University, 2024-04) DILGASA TUSHURA
Arbuscular mycorrhizal fungi play a crucial role in plant health by enhancing nutrient uptake, improving soil structure, and supporting ecosystem stability.This study investigates the role of AMF in the soil-plant interactions across different land-use types in Loka Abaya Woreda, Sidama Region, Ethiopia.The study examines the influence of soil physicochemical properties and plant species diversity on AMF distribution, spore density, and root colonization in agroforestry, natural forests, and cash crop systems.Soil characteristics, including pH, nitrogen, phosphorus, organic carbon, electrical conductivity, and texture, were analyzed across four land-use systems: agroforest, natural forest, cash crop, and grassland, revealing significant variation among different plant species. The soils were slightly acidic to neutral, with pH values ranging from 5.73 to 7.56 and phosphorus concentrations varying from 0.0100 mg/g to 0.3120 mg/g. Plant diversity was assessed using random sampling, resulting in the collection of 414 soil samples. Root colonization rates varied significantly, with Citrus sinensis exhibiting the highest colonization in field soil (94.5%), while Ehretia cymosa Thonn and Euphorbia abyssinica showed lower rates. In natural forests, Lennea schimper had 100% colonization, while Dodonaea angustifolia L.f. exhibited the lowest (84%). AMF colonization and spore densities were generally higher in trap cultures compared to field soils, with the highest spore densities in Psidium guajava (2251 spores/100 g) and Balanites aegyptiaca (1228 spores/100 g). Cash crops like Coffee arabica showed 100% AMF colonization and the highest spore density (838 spores/100 g in field soil). AMF analysis was conducted using Pearson's correlation, with data processed using SPSS software version 24.The study identified 30 AMF morphospecies from eight genera, with five genera Glomus, Acaulospora, Claroideoglomus, Enterophospora, and Rhizophagus intraradices showing significantly higher spore production, contributing 43.50%, 32.33%, 8.46%, 4.23%, and 3.62% of the total spore count, respectively. Notably, no single AMF species dominated across all land-use types, but four species Glomus sp.2, Claroideoglomus sp.1, Glomus mosseae, and Acaulospora sp.2 were commonly found, highlighting their ecological significance. The study found a positive correlation between spore density, root colonization, organic carbon, and nitrogen levels, while high phosphorus and soil pH negatively impacted AMF abundance. These findings emphasize the importance of agroforestry and natural forests in maintaining AMF diversity and enhancing soil health. The study recommends further research into AMF dynamics, particularly across different seasons and with molecular techniques, to enhance the understanding and application of AMF in agricultural systems.
ISOLATION, CHARACTERIZATION AND EVALUATION OF SYMBIOTIC EFFICIENCY OF INDIGENOUS RHIZOBIA FROM TRAP CULTURES IN BORICHA AND LOKKA ABAYA DISTRICT, SIDAMA REGION, ETHIOPIA
(Hawassa University, 2024-11) WAKWAYYA AMSALE
The excessive use of chemical fertilizers to boost crop yields has significant environmental drawbacks, including soil degradation, water contamination, and greenhouse gas emissions. Additionally, these fertilizers are often costly, making them inaccessible to many smallholder farmers. Leguminous crops play a crucial role in sustainable agriculture, contributing to soil fertility and crop productivity through their symbiotic relationship with rhizobia, which fix atmospheric nitrogen. Identifying and utilizing effective indigenous rhizobia is vital for improving legume yields, as these microorganisms are well-adapted to local environmental conditions, offering a cost-effective and eco-friendly alternative to chemical fertilizers. This study was aimed at isolation and characterization of indigenous rhizobia from soils in Boricha and Lokka Abaya districts in Sidama, Ethiopia, using groundnut and chickpea plants as a trapping host. Fourteen rhizobial isolates were successfully obtained after presumptive and authentication tests. All isolates tolerated alkaline conditions at pH 8, with 10 showing acid tolerance at pH 4. Most isolates grew at pH 5, except NiG2, NiG8, and NiC12, while nine tolerated pH 10. None of the isolates grew at pH 11. Notably, NiG8 was the only isolate capable of solubilizing tri-calcium phosphate. In metal resistance assessments, most isolates demonstrated growth on YEMA medium with aluminum, copper, and zinc, with 10 showing tolerance. Eight isolates exhibited resistance to manganese, and six to cobalt, while only NiG5, NiG8, and NiC12 tolerated mercury. Host range tests revealed significant host specificity and variability; Eight isolates nodulated soya bean effectively, six nodulated the common bean variety "Tafach," seven the "Nasir" variety, and five were effective on fava bean. No isolates nodulated lentil. Further analysis of symbiotic effectiveness showed significant differences (p<0.05) in nodule number, nodule dry weight, and shoot dry weight in fava bean, soya bean, groundnut, Tafach and Nasir. Most isolates exhibited high symbiotic effectiveness, often surpassing the nitrogen control and commercial inoculants. Isolates NiC4 and NiC7 demonstrated high effectiveness on chickpea, with values of 129% and 99.1%, respectively. On groundnut, NiG3 and NiG8 reached 103.4% effectiveness, with NiG6 also achieving 120% on the "Tafach" variety. For variety Nasir NiG6 showed 118.9% effectiveness, and NiG10 recorded 95.9%. These findings highlight the diversity and potentials of indigenous rhizobia to enhance legume productivity and soil fertility.
ISOLATION, CHARACTERIZATION AND EVALUATION OF SYMBIOTIC EFFICIENCY OF INDIGENOUS RHIZOBIA FROM TRAP CULTURES IN BORICHA AND LOKKA ABAYA DISTRICT, SIDAMA REGION, ETHIOPIA
(Hawassa University, 2024-11) WAKWAYYA AMSALE
The excessive use of chemical fertilizers to boost crop yields has significant environmental drawbacks, including soil degradation, water contamination, and greenhouse gas emissions. Additionally, these fertilizers are often costly, making them inaccessible to many smallholder farmers. Leguminous crops play a crucial role in sustainable agriculture, contributing to soil fertility and crop productivity through their symbiotic relationship with rhizobia, which fix atmospheric nitrogen. Identifying and utilizing effective indigenous rhizobia is vital for improving legume yields, as these microorganisms are well-adapted to local environmental conditions, offering a cost-effective and eco-friendly alternative to chemical fertilizers. This study was aimed at isolation and characterization of indigenous rhizobia from soils in Boricha and Lokka Abaya districts in Sidama, Ethiopia, using groundnut and chickpea plants as a trapping host. Fourteen rhizobial isolates were successfully obtained after presumptive and authentication tests. All isolates tolerated alkaline conditions at pH 8, with 10 showing acid tolerance at pH 4. Most isolates grew at pH 5, except NiG2, NiG8, and NiC12, while nine tolerated pH 10. None of the isolates grew at pH 11. Notably, NiG8 was the only isolate capable of solubilizing tri-calcium phosphate. In metal resistance assessments, most isolates demonstrated growth on YEMA medium with aluminum, copper, and zinc, with 10 showing tolerance. Eight isolates exhibited resistance to manganese, and six to cobalt, while only NiG5, NiG8, and NiC12 tolerated mercury. Host range tests revealed significant host specificity and variability; Eight isolates nodulated soya bean effectively, six nodulated the common bean variety "Tafach," seven the "Nasir" variety, and five were effective on fava bean. No isolates nodulated lentil. Further analysis of symbiotic effectiveness showed significant differences (p<0.05) in nodule number, nodule dry weight, and shoot dry weight in fava bean, soya bean, groundnut, Tafach and Nasir. Most isolates exhibited high symbiotic effectiveness, often surpassing the nitrogen control and commercial inoculants. Isolates NiC4 and NiC7 demonstrated high effectiveness on chickpea, with values of 129% and 99.1%, respectively. On groundnut, NiG3 and NiG8 reached 103.4% effectiveness, with NiG6 also achieving 120% on the "Tafach" variety. For variety Nasir NiG6 showed 118.9% effectiveness, and NiG10 recorded 95.9%. These findings highlight the diversity and potentials of indigenous rhizobia to enhance legume productivity and soil fertility.
ISOLATION, CHARACTERIZATION, SYMBIOTIC EFFECTIVENESS AND HOST RANGE OF RHIZOBIA TRAPPED USING COMMON BEAN (Phaseolus vulgaris) FROM FARMERS FIELD IN HAWELLA DISTRICT; SIDAMA REGION
(Hawassa University, 2024-05) DEMEKECH DANIEL
Rhizobia differ greatly in their symbiotic properties and efficiency in nitrogen fixation and therefore, the selection of highly effective strains is of great importance when attempting to achieve a successful preparation of rhizobial inoculants. The aim of this study was to isolate, characterize, and evaluate symbiotic effectiveness and host range of rhizobia trapped from small holder farmers’ fields in Hawella district of Sidama regional state using common bean. A total of 8 bacterial isolates were trapped from different soil samples. Of these, only five isolates were authenticated as rhizobia. These five isolates showed differences in various presumptive, cultural, biochemical and physiological characteristics. The results revealed that the indigenous common bean rhizobia isolates considerably differ in their symbiotic efficiency. Two rhizobial isolates (CBR7 and CBR8) significantly produced high nodule number, nodule dry weight and shoot dry weight (p<0.05). The remaining three isolates were not effective in fixing atmospheric nitrogen with the host plants. In addition, all the five isolates formed nodules faba bean, alfalfa and lentils exhibiting potential host promiscuity. Isolates CBR7 and CBR8 exhibited high N2 fixation efficiency and can be recommended for further evaluation to use them as inoculants for different legumes. Furthermore, we recommend detailed molecular characterization to determine their phylogenetic and taxonomic positions.
NEGLECTED AND UNDERUTILIZED ROOT AND TUBER CROPS, THEIR PROVISIONING ECOSYSTEM SERVICES, AND TRADITIONAL MANAGEMENT PRACTICES, IN MERAB BADAWACHO WOREDA, HADIYA ZONE, CENTRAL ETHIOPIA
(Hawassa University, 2024-05) TARIKU TAREKGN
Root and tuber crops are high-yield potential crops mainly grown for multiple purposes in the home gardens in Ethiopia. Despite these benefits, they are mostly neglected and underutilized as well as are given little attention by both policy-makers and researchers. This study evaluated the neglected and underutilized root and tuber crops (NURTCs), their provisioning ecosystem services, and traditional management practices in Hadiya zone, Central Ethiopia. The study site was selected using a purposive sampling technique. Relevant data were gathered using questionnaire household survey, semi-structured interviews, field observations, and key informant interviews. The study engaged a total of 320 sample households from the selected sites. The most widely used NURTCs in terms of food; income and traditional medicine were Enset (Ensete ventricosum (Welw.) Cheesman), Taro (Colocasia esculenta (L.) Schott)), Sweet potato (Ipomoea batatas (L.) Lam), Ethiopian potato (Plectranthus edulis (Vatke) Agnew) and Yams (Dioscorea spp.). These crops delivered multiple provisioning ecosystem services, including source of food, income, livestock feed and traditional medicine. The crops were used as main food and food supplements by the majority of households, contributing a major share to the traditional food system. About 83.4%, 56.5% and 33.4% of the households used the crops for income generation, traditional medicine and animal feed, respectively. The major traditional management practices were mixed cropping, crop rotation, fallowing land, storing of planting materials, and pest management. Households practiced manual methods to control weed, pest and disease. They used different indigenous soil fertility management mechanisms, with 98.4% of them using animal manure to increase soil fertility, productivity and ecosystem services. Despite those benefits and rich management systems, the production of the crops were declining as witnessed by about 85% of the households, indicate their vulnerability to genetic erosion. An increase in population size, shrinking in home-garden size, and new weeds, pests and disease were the main contributor for their decline. Overall, the NURTCs provide multiple ecosystem services such as food, income, livestock fodder, and medicine and are mainly managed by traditional knowledge and skill. As they are the vital part of livelihood systems, there should be a support from all key stakeholders regarding addressing the bottlenecks constraining the production, productivity and gene conservation of the NURTCs that are effective in giving greater yield per unit farm, and providing multiple provisioning ecosystem services.