IN VITRO AND IN VIVO INVESTIGATION OF PLANT GROWTH PROMOTING AND BIOPROTECTING RHIZOBACTERIA ON EARLY MAIZE PLANT GROWTH

The use of soil microorganisms as biofertilizers and biocontrol agents in agriculture is important in maintaining the soil ecological balance and sustainability of agroecosystems. Rhizobacteria were isolated and identified from the rhizosphere of matured field grown with maize (Zea mays L.) at the field of Federal University of Agriculture, Abeokuta teaching and  research  farm. The effect of inoculation of maize seeds (Oba super 2) with rhizobacteria on growth promotion and bioprotection against Fusarium moniliforme were investigated in vitro and in pot experiment in a screen house. Eight treatments representative of at least all the different genera of the isolated rhizobacteria and an uninoculated control in both cases were used. Treatments were replicated 3 times in a completely randomised design. Data obtained were subjected to analysis of variance (ANOVA) and means separated using Fisher’s LSD test (P<0.05). Fifty four rhizobacteria were isolated and identified consisting of Bacillus cereus (22%), Pseudomonas aeruginosa (2%), Micrococcus acidophilus (26%), Proteus morganii (11%), Staphylococcus aureus (9%), Streptococcus faecium (28%) and Staphylococcus parasiticus (2%). The in-vitro growth promotion study revealed that there was no significance difference among treatments in plant height and root mass. However, Pseudomonas aeruginosa and Bacillus cereus significantly increased the plant height length (0.13-0.21) and root mass (0.10-0.12) above control. The in-vitro biocontrol screening revealed that none of the treatments except Pseudomonas aeruginosa and Bacillus cereus showed inhibition (2.0-2.5mm) against Fusarium moniliforme. Results from the screen house study showed that treatment significantly increased the plant height and root mass except Staphylococcus aureus and Staphylococcus parasiticus and only Bacillus cereus and Pseudomonas aeruginosa increased only the root mass.  Bacillus cereus, Pseudomonas aeruginosa, Micrococcus acidophilus, Proteus morganii greatly reduce the recovery of the pathogen (Fusarium moniliforme) from infected seeds whereas Streptococcus faecalis was slightly effective. It was observed from the study that only Pseudomonas aeruginosa and Bacillus cereus had traits of plant growth and bioprotection and as such they have prospects for use as plant growth promoting and as biocontrol.Â

COMPARATIVE EFFECTS OF ARBUSCULAR MYCORRHIZAL AND DEGRADED SAWDUST ON GROWTH AND YIELD CHARACTER OF PEPPER (CAPSICUM SPP)

The experiment was conducted to evaluate the effect of Arbuscular mycorrhiza  and degraded sawdust on growth and yield characters of bell pepper (Capsicum annum L.)  The experiment was 2x4 factorial arranged in a Completely Randomized Design (CRD)) with four replicates. The eight treatments were combinations of two early maturing varieties of bell peppers (PEP and Gombe) and soil amendments (degraded sawdust, Glomus etunicatum and steam sterilized homogenous soil as control (C). The two varieties of bell pepper differed significantly in growth and fruit parameters. Variety Gombe had higher plant  height (22.2cm) and produced more fruits of bell pepper (1.7) than variety PEP inspite of its larger leaf area (23.1cm2) by the latter. The results also showed that soil amendment with degraded sawdust alone and combination with Glomus etunicatum improved the growth parameters such as plant height, stem girth, leaf area as well as numbers of flowers and fruits of bell pepper. The interaction of pepper and soil amendments was significant on all the growth and yield parameters with varieties exhibiting differential reactions to the soil amendment treatments. Soil amendments with degraded sawdust and combination of degraded sawdust with Arbuscular mycorrhiza  had positive effects on the growth and yield characters of both varieties of pepper used (PEP and Gombe).   &nbsp

PLASMID PROFILE OF ANTIBIOTIC RESISTANT BACTERIA IN SACHET WATER SAMPLES SOLD IN ABEOKUTA, SOUTHWEST, NIGERIA

Antibiotic sensitivity pattern of bacterial isolates obtained from sachet water from Abeokuta, Ogun State, Nigeria was investigated.ª¤? A total of 300 sachet water samples were collected during the dry and rainy season of 2011 to 2012. Selected physicochemical analysis of the sachet water showed a pH range of 5.5-6.5, turbidity of 1.0 «¤??1.5 NTU and temperature of 28-300C. The mean aerobic mesophilic bacterial count of the sachet water samples ranged from 13.4 x 103 «¤?? 18.7 x 103 CFU/mL, while the mean total coliform count ranged from 0.153 - 0.163 x 103 CFU/mL. The physicochemical parameters of the sachet water samples were within the WHO standard for potable water. Bacteria isolated from sachet water samples include Escherichia coli, Klebsiella sp, Enterobacter sp and Pseudomonas aeruginosa. Most of the isolates were highly sensitive to Levoxin and Ceftazidime. Plasmid analyses revealed that there were detectable plasmids in 7.1% of the 14 multi-drug resistant isolates. Cured plasmid encoded resistant isolates were susceptible to Ceftazidime, Ceftriaxone, Gentamycin, Augmentin and Streptomycin

STABILITY OF BIOSURFACTANT PRODUCED BY PSEUDOMONAS TAENENSIS

Biosurfactants are one of the microbial bioproducts that are naturally synthesized and are applicable for many industrial purposes. In this study, antibacterial, stability and antibiotic susceptibility of biosurfactant was evaluated. Biosurfactants produced from different substrates (groundnut cake, cassava flour waste, pome, cooking oil, engine oil, cassava waste water, molasses, cassava peel, potato) by Pseudomonas taenensis were evaluated for antibacterial activity using agar well diffusion method. Antibiotics susceptibility of Pseudomonas taenensis was carried out using different antibiotics (augmentin, ofloxacin, tetracyclin and ciprofloxacin, cotrimoxazole, pefloxacin, amoxylin, ceftriazone, nitrofuranton and gentamycin). The stability of the biosurfactant was evaluated by adjusting the biosurfactant to: pH (2, 4, 6, 8, 10 and 12) using 1M NaOH and 1M HCl, temperature (4, 30, 37, 55, 75 and 100 °C) and NaCl (0, 5, 10, 15, 20 and 25 %). Results showed that only biosurfactant produced using cassava waste water as substrate was sensitive to Escherichia coli while biosurfactant produced using cassava flour waste, pome and molasses were sensitive to Staphylococcus aureus. Biosurfactant-producing isolate (Pseudomonas taenensis) was sensitive to four antibiotics (augmentin, ofloxacin, tetracyclin and ciprofloxacin) and resistant to six antibiotics (cotrimoxazole, pefloxacin, amoxylin, ceftriazone, nitrofuranton and gentamycin). Biosurfactant was stable over all the wide ranges of pH, temperature and sodium chloride concentrations investigated. This study therefore revealed that biosurfactant have good stability, thus, could survive environmental stress; Not all biosurfactant and biosurfactant producers have antimicrobial and antibiotic property.   &nbsp

SIAM WEED (Chromolaena odorata) AND COWDUNG COMPOST EFFECTS ON PHYSICOCHEMICAL PROPERTIES, YIELD and MINERAL NUTRITION OF TOMATOES(Lycopersicon esculentum L)

Greenhouse trials were conducted to evaluate the effects of  siam weed (chromolaena odorata) and cowdung compost on  physicochemical properties, yield and mineral nutrition of tomatoes(lycopersicon esculentum l). The nutritional value of tomato makes it one of the crop that is a daily household consumption by every family.Compost was prepared in this study from Siam weed (Chromolaena odorata) and cowdung. Three compost samples were prepared from Cowdung and siam weed at ratio 100g: 100g (sample A),  200g chopped siam weed (sample B) and 200g cowdung (sample C). These three samples were composted in plastic drums perforated for aeration and each sample was replicated three times. The content in the drums were regularly turned and monitored at 1, 10, 30 and 60 days for physicochemical properties. The physicochemical and mineral element analyses of the compost were carried out using standard procedures.The pH of the composted samples ranged between 5.8 to 6.9. Nitrogen, phosphorus and potassium contents increased with days of composting while those of heavy metals decreased. The result of plant height for the two varieties ranges  between 5.31-119.8, number of  fruits is between 11-21 and the yield (kg) parameter ranges between 0.76-1.91. Treatment. A gave higher mineral element over other treatment applied. The order of mineral elements contributed to the fruits were as follows treatments A>C>B>D   &nbsp

Microbial Dynamics and Biogas Production during Single and Co-digestion of Cow Dung and Rice Husk

Anaerobic digestion is achieved by the combined effort of hydrolytic, acetogenic and methanogenic bacteria. Microbial dynamics and biogas production during anaerobic digestion of cow dung and rice husk were studied in this research. The experiment lasted for 30 days using a 10 L scale bio-digester. All proximate parameters reduced significantly after digestion for CD (cow dung), RH (rice husk), and CD:RH (cow dung and rice husk) except moisture content, which increased for all substrates. Ash content (1.08-1.67 mg) and crude fibre (1.27-1.96 mg) increased in CD only. The pH ranges for the substrates were CD (7.0-7.5), RH (6.1-7.6), and CD:RH (6.1-7.8). Temperature ranges were CD (27.4 oC-33.5 oC), RH (27.2 oC-33.3 oC) and CD:RH (27.3 oC-33.4 oC). The total biogas production of the substrates and components of each gas produced were, CD (4327.65 cm3 : 62.4 % CH4, 37.4 % CO2, 0.2 % H2S), RH (150 cm3 : 100 % CO2), and CD:RH (4730.55 cm3 : 73.8  % CH4, 25.8 % CO2, 0.4 % H2S). Percentage distribution of the digester’s microflora include aerobes (40.75 %), anaerobes (31.25 %), fungi (25 %) and methanogenic bacteria (3 %). Hydrolytic bacteria and fungi isolated were Bacillus spp, Enterobacter spp, Pseudomonas spp, Proteus spp, Micrococcus spp, Aspergillus spp, Penicillium spp and Streptococcus spp. Acetogens isolated were Clostridium spp, Streptococcus spp and Pseudomonas spp. Methanococcus spp and Methanobacterium spp were the only isolated methanogens. Rice husk produced the least amount of biogas

Potential Biosurfactant-producing Bacteria from Pharmaceutical Wastewater using Simple Screening Methods in South-West, Nigeria

Emerging multiple opportunities for industrial production and environmental applications have focused increasing research attention on biosurfactants in recent years. Hydrocarbon-polluted soils have proved a major source of biosurfactant-producing bacteria. In this study an alternative method of producing biosurfactants was established, based on pharmaceutical effluents. Pharmaceutical effluents are a rich source of complex organic compounds with potential as a substrate for microbial biosurfactant production. A successful biosurfactant screening assay is achieved when a combination of different methods are employed. Biosurfactant producing bacteria were isolated from pharmaceutical effluent and identified by biochemical methods. The best biosurfactant producer was identified by a molecular method. The biosurfactant screening techniques employed were drop collapse assay, haemolytic assay, oil spreading assay, bacteria adhesion to hydrocarbon assay and emulsification assay. Analysis of haemolytic activity indicated that 35 isolates (44.30 %) produced beta-haemolysis, 12 isolates (15.19 %) produced gamma-haemolysis, while 32 isolates (40.51 %) produced alpha-haemolysis. The highest zone of clearance was 42.0±1.73 by isolate DF7 and lowest zone of clearance was obtained from isolate GC5 of 12.0±0.73. Screening of the 35 isolates using the oil spreading test showed that 28 isolates (80.0 %) were positive, while 7 isolates (20.0 %) were negative. The highest zone of clearance for the oil in water was 19.0±0.1 by DF1 while the lowest zone was 4.3±0.33 by MB3. The drop collapse test revealed that 22 isolates (78.57 %) were positive and 6 isolates (21.43 %) were negative. At 0 h, the highest emulsification percentage was 74.4 % by Bacillus licheniformis and the lowest was 42.5 % by Arthrobacter globiformis. After 24h, the highest emulsification value (69.23 %) was obtained for Bacillus clausis, while the lowest value (30.84 %) was obtained for Arthrobacter globiformis. The findings demonstrated the ability of the isolates to produce biosurfactant, and confirmed the capacity of Bacillus clausis isolated from pharmaceutical effluents as a potential bacteria for biosurfactant production

INHIBITION OF Fusarium oxysporum Pathogenic Fungus USING COMPOST EXTRACT FROM Chromolaena odorata (SIAM WEED) AND COW DUNG

The study was conducted to evaluate the efficacy of composts extract from cow dung and Chromolae-na odorata in controlling Fusarium oxysporum. Three compost samples were prepared in this study from Siam weed (Chromolaena odorata) and cow dung. Sample A was prepared from Cow dung and siam weed at ratio 100g: 100g, Sample B was prepared from 200g chopped siam weed and sample C contained 200g cow dung. These three samples were composted in plastic drums perforated for aera-tion and each sample were replicated three times. The content in the drums were regularly turned and monitored for 1, 10, 30 and 60 days. The microbiological analysis of the composts were determined using standard procedures. The inhibitory activities of the sterilised compost extracts on the F. ox-ysporum were determined using agar well diffusion method. The bacterial, coliform and fungal loads ranged from 1.50 – 9.0 × 107 cfu/ml, 0.3 – 6.0× 107 cfu/ml and 0.1 – 2.50 × 107 cfu/ml respectively. Inhibitory activities of the compost extracts on F. oxysporum at different days of composting increased with days of composting. The highest zone of inhibition was recorded by extract from compost pre-pared from C. odorata at 60 days of composting, closely followed by extract from compost prepared from mixture of cow dung and C. odorata at 60 days of composting. No antifungal activity was found in all extracts from the 24h-composts. Highest disease severity was recorded in extract of 24 h and on control. All extract at 60 days of fermentation were healthy The study therefore revealed the potentials of extracts from Chromolaena odorata and cow dung for the inhibition of Fusarium oxysporum of many crops

CHANGES IN MICROBIOLOGICAL AND PHYSICO-CHEMICAL PROPERTIES DURING COMPOSTING OF SIAM WEED (Chromolaena odorata) AND COWDUNG

Three compost samples were prepared in this study from Siam weed (Chromolaena odorata) and cowdung. Sample A was prepared from Cow dung and siam weed at ratio 100g: 100g, Sample B was prepared from 200g chopped siam weed and sample C contained 200g cowdung. These three sam-ples were composted in plastic drums perforated for aeration and each sample were replicated three times. The content in the drums were regularly turned and monitored at 1, 10, 30 and 60 days for mi-crobiological and physicochemical properties. The microbiological and physicochemical analyses of the compost were carried out using standard procedures. Bacterial, Coliform and Fungal count in-creased from day 1 to the 30th day and thereafter decreased from 30th day to the 60th day in all the composting samples. The bacteria species isolated and identified were Pseudomonas fragilis, Pseu-domonas nitrificans, Proteus mirabilis, E. coli, Streptococcus faecium, Micrococcus luteus, Clostridium perfringes, Bacillus cereus, Proteus morganii, Micrococcus acidophilus. Fungal species were Aspergil-lus flavus, Aspergillus fumigatus, Fusarium oxysporium, Penicillum chrysogenum, Aspergillus niger, Mucor sp. and Saccharomyces cerevisiae. The pH of the composted samples ranges between 5.8 to 6.9. The nitrogen, phosphorus and potassium content increased with days of composting but the heavy metals decreased with days of composting. The sulfatase, phosphatase, dehydrogenase, amyl-ase and cellulose enzymes in the three samples increased from day 1 to the 60th day. Sulfatase en-zyme which was the highest ranged from 25 to 76.5% in the three sample, phosphatase (14 to 60.5%), dehydrogenase (20.5 to 55.0%), cellulose (16.5 to 49%) and amylase which was the least enzyme recorded ranged from 5.0 to 38%

High level antibiotic resistance and relatedness of Staphylococcus aureus in raw cow milk and soft cheese in Abeokuta, Nigeria.

Prevalence of pathogenic S. aureus with multiple antibiotic resistance in raw milk and soft cheese in Abeokuta, kept rising and is now becoming a serious public health concern. Therefore, the S. aureus resistance profiles and their resistance relatedness in raw cow milk and soft cheese were studied.A total of 100 raw cow milk samples were randomly collected from boarded and free ranged cattle in different herds in Abeokuta, Nigeria while same number of samples of soft cheese were randomly purchased from various hawkers in different popular markets (Ologborugburu, Alabata, Kotopo, Ita-Oshin, and Lafenwa) in Abeokuta. S. aureus and other bacteria were isolated and biochemically characterized while coagulase S. aureus were tested for their antimicrobial resistance pattern and their resistance relatedness was determined using Dendro-UPGMA construction software.High occurrence rate of E.coli (22.1%), Citrobacter freundii (18.3%) and Pseudomonas fluorescens (16.4%) were found in milk and Pseudomonas fluorescens and Klebsilella specie (14.0%) in soft cheese. A significant rate of coagulase positive Staphylococcus aureus of 9.6% and 5.3% was found in milk and soft cheese samples respectively. Antibiotic resistant pattern show significant 100% resistance of S. aureus strains to Tetracycline, Penicillin and 50% to Amoxicillin while 100% and 92.9% show MIC > 16ug/ml to Amoxicillin, Tetracycline and Penicillin respectively. Similarly, 100% resistance to Tetracycline and Penicillin was shown by the S. aureus obtained in Soft cheese while only 50% show resistance to cefotaxime. All the 24 coagulase S. aureus isolates were divided into two major clusters Sa and Sb with 31% resistance relatedness. The Sa clusters were further divided into two sub-clusters sa1 and sa2 with 34% antibiogram resistance relatedness while sa2 was further divided into two major clades sa2v and sa2i having 46% resistance relatedness. Of 14 S. aureus strains found to belong to clade sa2v, 4 strains were found in milk sold in Ologborugburu, 2 in Alabata and1 in Kotopo. S. aureus strains with same antibiogram profile were found in 4 samples of Soft cheese sold in Kotopo, 3 in Ita-oshi and 3 in Lafenwa. Only 1 S. aurues strain was found to belong to sb cluster. Rapid dissemination of resistant S. aureus across Abeokuta with similar antibiotic resistant profile call for urgent surveillance and practical preventive action against retailing and consumption of raw milk and soft cheese in Abeokuta, Nigeria.Keywords: S. aureus, antibiotics, resistance, milk, soft chees