Antagonistic Potentials of Actinomycetes Isolated from Coastal Area of Niger Delta against Citrus sinensis (Sweet Orange) and Lycopersicum esculentum (Tomato) Fungal Pathogens

Abstract

The antagonistic potentials of actinomycetes isolated from coastal area of Niger Delta against Citrus sinensis (sweet orange) and Lycopersicum esculentum (tomato) fungal pathogens were investigated. Marine sediment and water samples were collected from ten (10) different points from Onne Light Flow Terminal Seaport situated in Eleme Local Government Area of Rivers State, Nigeria. The actinomycetes were isolated on Glycerol Starch Casein Nitrate Agar using spread plate technique as well as characterized phenotypically and biochemically using API - 20 A tests. A total of fifteen (15) isolates were identified in the genera Streptomyces and Actinomyces using API identification system. These strains were screened for antagonistic effects against the isolated fungal phytopathogens using cross streak antagonistic method on Glycerol Starch Casein Potato Dextrose Agar. The result revealed that amongst the 15 marine aactinomycetes strains (MAB1 - MAB15), 5 (33.33 %) and 4 (26.67 %) strains had no activities against Penicillium digitatum O1 and Fusarium solani T2 while 10 (66.67 %), 15 (100.00 %) and 11 (73.33 %) strains had total activities against Penicillium digitatum O1, Aspergillus niger O2, Rhizopus stolonifer O3, Rhizopus stolonifer T1 and Fusarium solani T2. Also, strains MAB8 and MAB15 had the strongest significant (P < 0.05) inhibition of 91.60 % on Penicillium digitatum O1 while MAB13 had the weakest significant (P < 0.05) inhibition of 33.30 % on Fusarium solani T2 mycelial growths. Thus, majority of actinomycetes strains (86.67 %) possess biocontrol potentials against these phytopathogens and could be promising alternatives to fungicides which are not eco - friendly.

Keywords: Actinomycetes, biocontrol, marine environment, Niger Delta, fungal phytopathogens

Cite this Article

Bright Obidinma Uba, Ebere Linda Okoye, Ogechi Jecinta Anyaeji_, Ogochukwu Chikaemerem Ogbonnaya. Antagonistic Potentials of Actinomycetes Isolated from Coastal Area of Niger Delta against Citrus sinensis (Sweet Orange) and Lycopersicum esculentum (Tomato) Fungal Pathogens. Research & Reviews: A Journal of Biotechnology. 2019; 8(3): 4–15p.