Department of Biotechnology
URI for this collectionhttps://rps.wku.edu.et/handle/123456789/45780
Department of Biotechnology
Browse
5 results
Search Results
Item IAA-PRODUCING BACTERIA FROM THE RHIZOSPHERE OF CHICKPEA PLANT (Cicer arietinum L.) ISOLATION CHARACTERIZATION AND THEIR EFFECTS ON PLANT GROWTH PERFORMANCE(Wolkite University, 2024-01-01) DEBEBE LANDINA LATAIndole-3-acetic acid (IAA), a crucial plant hormone, regulates diverse physiological processes. Plant growth-promoting rhizobacteria naturally present in soil can enhance plant growth by producing IAA. This study aimed to isolate and characterize IAA-producing bacteria from the chickpea (Cicer arietinum L.) rhizosphere and evaluate their effects on plant growth. A total of 118 bacteria were isolated from 54 chickpea rhizosphere samples collected from Gurage Zone, Ethiopia. Purified isolates were designated as GAC; a Salkowski colorimetric was used for IAA production; and Bergey's systematic bacteriology manual was used for biochemical examination. The highest IAA-producing isolates were grown under various conditions and in vitro screened for their growth promotion traits. A PCR investigation was performed to determine the presence of IAA and nitrogen-fixing genes, and the isolates were evaluated for greenhouse conditions. Out of 118, 27 isolates produced IAA and eight isolates with the highest IAA-production (22.88-26.47 μg/ml) were selected. Morphological and biochemical identification classified six isolates as Pseudomonas and two as Bacillus. Optimal conditions for IAA-production were observed at 500 μg/ml tryptophan, 35 °C, and pH 7.0. A 48-hour incubation was ideal, except for GAC-34 and GAC-73, which required 72 hours. GAC-2 isolate achieved optimal IAA production with sucrose (45.28 μg/ml) and lowest by GAC-92 with fructose (7.72 μg/ml), and GAC-91 isolate produced the optimum IAA level with tryptone (9.62 μg/ml) and lowest by GAC-34 with peptone (2.81 μg/ml). Selected isolates demonstrated nitrogen fixation by producing ammonia, changing the medium to a dark blue/yellow color. The GAC-118 isolate exhibited maximum phosphate solubilization (11.00 mm). GAC-118 isolate confirmed the presence of nifH, nifK, and ipdC genes. Greenhouse experiments revealed that these isolates significantly enhanced chickpea growth parameters (P≤0.05) compared to the control. Thus, uses of IAA-producing bacteria from chickpea rhizosphere could enhance Ethiopian crop productivity; further molecular identification and field studies needed.Item SCREENING PLANT GROWTH PROMOTING ATTRIBUTES OF RHIZOSPHERIC PSEUDOMONAS SPECIES FOR ABIOTIC STRESS TOLERANCE ON SORGHUM(Wolkite University, 2023-11-01) MEKDES MULUGETASorghum is an economically important crop that is used for food, feed, and biomass production worldwide. Despite its economic importance, sorghum productivity is affected by biotic and abiotic stresses. By encouraging plant water-use efficiency, osmotic stress tolerance, and root development, PGPR (Plant Growth-Promoting Rhizobacteria) application assists in preventing drought and improves plant resilience and survival in environments where water is scarce. Therefore, the application of (PGPR) in sorghum demonstrates promising potential for sustainable and resilient agricultural practices. The present study aimed to screen the growth-promoting attributes of Rhizospheric Pseudomonas spp. for abiotic stress tolerance in sorghum using a combination of techniques and approaches to gain a comprehensive understanding of the interactions between the Pseudomonas rhizospheric bacteria and the sorghum. Based on this there is a need to improve agricultural sustainability and chemical effects on the environment using PGPR. The sample was isolated from different areas of Ethiopia, and 210 isolated bacteria were screened using the serial dilution method. The response of PGPR was tested under temperature, pH, salt, and drought stress. The genes implicated in PGPR were amplified using PCR (polymerase chain reaction), and the bacteria were identified using 16S RNA. Based on biochemical tests 68 showed nitrogen fixation and 50 showed phosphate solubilization. Based on molecular examination, of the 68 isolates, 16 were positive amplifications for the nifH target amplicon and 10 for the acdS target amplicon, and of the 50 isolates, 21 were positive amplifications for the pqq target amplicon. Using the R software analysis, the Pseudomonas MS-22 isolate demonstrates its potential as a growth- promoting rhizobacteria; further research is required to identify optimal strains and application methods for sustained benefits. The implications of these findings extend to the realm of sustainable agriculture, where harnessing the potential of Pseudomonas MS-22 could pave the way for eco-friendly and efficient agricultural practices.Item THE PREVALENCE AND IDENTIFICATION OF ANTIBIOTICS RESISTANCE GENES IN COMMON UROPATHOGENS ATTENDING ATTAT HOSPITAL ETHIOPIA(Wolkite University, 2023-11-01) WONDWESEN MITIKU SISAYEUrinary tract infections (UTIs) are infections of the urinary framework (the kidneys, ureters, bladder, and urethra). UTI occurs when bacteria, primarily from the genital area or the stomach-related tract, stick to the entrance of the urethra and start to spread. In Ethiopia and the Gurage Zone specifically, there is a significant research deficit regarding the identification and prevalence of antibiotic resistance genes in common urinary tract bacterial infections. The aim of this study designed to estimate the prevalence of uropathogenic bacterial urinary tract infections and identify individuals with genes associated with antibiotic resistance at the Attat Hospital, Ethiopia. A cross-sectional study involved 384 across-section were involved in the current study patients from the Attat Hospital. Culture on Blood, Macconkey and Nutrient agar was carried out after a dipstick urine examination. Using the gram stain and biochemical testing, pathogenic bacteria were isolated and recognized. The Kirby Bauer disc diffusion method for determining antibiotic sensitivity and resistance employed erythromycin, cefepime, tetracycline, clarithromycin, vacomycin, pencilin, and ciprofloxacin. Genomic extraction and PCR amplification for detection of tetraA , vanA and blaSHV antibiotics resistance gene were done. According to the proportion of participants who experienced UTIs during the research period, the prevalence was 75.0%. Staphylococcus aureus was the sole Gram- positive bacteria found; other Gram-negative bacteria included Escherichia coli, Klebsiella pneumonia, Entrobactor aerogenes, Protus valigaris, Proteus mirabilis, and Pseudomonas aeruginosa. The most often isolated bacterium was Escherichia coli (49.3%), whereas P. aeuruginosa was the least frequent (2.8%). The most effective antibiotic for all bacteria was ciprofloxacin, and the isolates tested negative for tetracycline. The molecular investigation identified three different genes with E. coli, K. pnumoniae, and S. aeurus, respectively: 53.8% tetA, 54.2% blaSHV, and 78.6% vanA. In order to prevent multidrug resistance, which would otherwise have an influence on the rising cost of care, the study advises regular surveillance and investigation of antibiotic use in the therapy of UTI. The need for future molecular analysis of antibiotic resistance genes cannot be overstated.Item ISOLATION AND MOLECULAR DETECTION OF ANTIBIOTIC RESISTANCE GENE OF STAPHYLOCOCCUS AUREUS FROM COW MILK SAMPLE IN WOLKITE DISTRICT ETHIOPIA(Wolkite University, 2023-11-01) AYANSA KEBENESSA MEDEKSAStaphylococcus aureus is one of the most frequent organisms known to cause food poisoning and other diseases including humans and animals. Raw milk is known to be a major means of transmission of this pathogenic bacterium to humans and animals. This study aims to isolate, characterize, and molecular detection of antibiotic resistance genes for Staphylococcus aureus from cow milk samples collected from wolkite, Ethiopia. A total of 385 samples of cow milk were collected randomly. Each of the samples collected was serially diluted, cultured on blood agar, and incubated at 37 oC for 24hr and preliminary screening for possible Staphylococcus species isolate was conducted. The secondary screening for possible Staphylococcus aureus such as coagulase test, fermentation of mannitol salt agar, anti-biotic sensitivity tests, and molecular characterization for nuc gene and mecA genes were conducted. A total of 30 possible Staphylococcus species were isolated and 21 isolates were screened as S. aureus based on the advanced biological identification software. The rest of the isolates were found to be positive for catalase, triple sugar iron tests, cocci in shape, positive to gram staining, non- motile, and negative to vogues pressure tests. Some of them were coagulase- positive and 60% were positive to mannitol salt agar. All tested isolates were resistant to penicillin, 53.9% were multidrug-resistant and most of them were sensitive to clindamycin. Under the PCR detection of antibiotic resistance genes, 70% of the possible isolates were found to have the mecA gene while 80% were positive for the nuc gene. These isolates were predicted to be S. aureus subsp. aureus, S. cohnii, S. intermedius, and S. vitulinusin which nearly all of them have belonged to S. aureus subsp. aureus following the methods of advanced biological identification software identification tools. In conclusion, the recent isolates obtained from raw milk harbored specific genes responsible for disease-causing that were reported and available in the genomic DNA of S. aureus throughout the history of evolution.Item MICROPROPAGATION OF TWO BANANAS (MUSA SPP.) VARITIES USING SHOOT EXPLANT FROM GURAGE ZONE, ETHIOPIA(WOLKITE UNIVERSITY, 2024-04) GENET DARGEThe banana (Musa spp.) is one of the most important fruits for production and consumption due to its great nutritional importance. Nearly all banana genotypes are being threatened by bacterial wilt disease due to conventional propagation. Banana propagation rates achieved by tissue culture techniques are much higher than those reported by conventional methods. The objectives of this research were to develop a mass in vitro regeneration protocol for two elite banana dwarf Cavendish and ducase varieties from shoot tip explants. The experiment was laid out in CRD with three replications in factorial arrangement. Sodium hypochlorite (NaOCl) in three concentration levels (1, 2, and 5%) with 70% ethanol was used for surface sterilization. For controlling browning on explants at shoot initiation, explants were aseptically cultured on MS basal medium supplemented with 25mg, 50mg, ascorbic acid, and 1g and 2g of activated charcoal. Then the initiated shoots were transferred to MS basal media supplemented with 2, 2.5, or 3 mg/l of BAP alone and in combination with 0.5 mg/l of Kn. Plantlets were planted on different mixes of soil in (2:1:1). The sterilization experiment showed that 2% NaOCl was found to be effective. The results showed that from levels of antioxidant treatments up to 85%, initiated shoots survived medium containing 2 g/l activated charcoal. The use of 2g AC and 50mg AA as anti-browning agents in the medium for banana explants was suitable for shoot tip culture. On the shoot multiplication, maximum shoots per ex-plant (8.33) were obtained on a medium containing 3 mg/l BAP and 0.5 mg/L KN. The highest increase in root length was observed with the 80 g/l bulla, resulting in 6.90cm on the du case variety. The acclimatization experiment showed 100% plantlet survival in all media mixtures. In this study, among the two cultivars tested, dwarf Cavendish was found to be more responsive to in vitro propagation techniques.