Browsing by Author "Otaye, D. O."

Now showing 1 - 3 of 3

Antimicrobial Activity of Streptomycetes Isolated from the Mau Forest Complex in Kenya
(Egerton University, 2018-01) Njoroge, H. W.; Muia, A. W.; Boga, H. I.; Otaye, D. O.
Search for newprinciples in biocontrol of plant pathogens different from the classical fungicides is of worldwide interest. Members of the genus Streptomyces are known to produce about 80% of all known antibiotics in the world. These antibiotics have beenapplied in medicine, veterinary and in agriculture. Presumptive Streptomyces from the Mau Forest Complex were isolated from soils obtained from different sites within the Mau Complex. 270 isolates were screened for antimicrobial activity against selected plant pathogenic bacteria and two fungal plant pathogens i.e. Erwinia carotovora, Xanthomonas campestris pv. campestris, Pseudomonas savastonoi pv. phaseolicola, Fusarium moniliforme, Ascochyta rabie; the reference cultures were: Staphylococcus aureus ATCC25923; Escherichia coli ATCC 25922; Pseudomonas aeruginosa ATCC 27853 and Bacillus subtilis ATCC 6633. 14 (0.05%) of the isolates showed antibacterial activity against the test bacteria while 39 (0.14%) isolates had antifungal activity. Ethyl acetate extracts of culture filtrates from the isolates produced significantly different (P<0.05) inhibitory effects to some of the tester microorganisms. Five of these isolates had both antifungal and antibacterial activity. There were further characterized using biochemical, microscopy and morphological methods. These methods showed that they were Gram positive and had similarities to members of the genus Streptomyces. The study found that soils from Mau Forest complex harbor diverse group of bacteria including Streptomyces species that could be exploited for control of plant diseases. There is need to establish their effectiveness in green house and field studies.
The Use of Trichoderma Viride C. in the Management of Chilli Root Knot Disease in Nakuru County, Kenya
(Egerton University Institutional Repository, 2018-07) Waweru, C. M.,; Muthamia, J. M.,; Otaye, D. O.
The Use of Trichoderma Viride C. in the Management of Chilli Root Knot Disease in Nakuru County, Kenya
(Egerton University, 2018-01) Waweru, C. M.; Muthamia, J. M.; Otaye, D. O.
Chilli (Capsicum annum L.) is a sub-tropical crop grown for its pungent tasting fruits and sour leaves. Kenya is among the largest exporters of chilli. Chilli yields are largely reduced by sedentary nematodes (Meloidogyne spp). Chillis are prone to root knot nematodes which reduce the quality and yields. This study focused on the use of Trichoderma viride as a potential biocontrol agent against root knot nematodes. Investigation was done on the effect of Trichoderma viride at different concentrations on the plant height, leaf number, stem diameter, number of galls, nitrogen and phosphorous levels in chilli infected with root knot nematodes. Four dilutions of Trichoderma viride were obtained through serial dilution (100%, 50%, 25% and 12.5%). Bio-control efficacy of Trichoderma viride against the root knot nematodes was tested under glasshouse and field conditions. Evaluation after treatment of plants with T. viride isolates showed that there was no significant effect on plant heights, number of galls, stem diameter or leaf number in chilli. There was significant difference in the nitrogen and phosphorous levels when different treatments of Trichoderma viride were applied on chilli with root knot nematodes