African Journal of Infectious Diseases Research

ISSN 2756-3340

African Journal of Infectious Diseases Research ISSN 2756-3340 Vol. 11 (1), pp. 001-012, January, 2024. © International Scholars Journals

Full Length Research Paper

Harnessing potential antagonistic bacteria for managing Magnaporthe grisea in rice crops

David P. Tokpah1, 2*, Hongwei Li1, John T. Newmah2, Zipporah Page2, Zogbo Luther2, Charles F. King2, Melissa S. Smith2 and Victor M. Voor2

1Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Agriculture, Nanjing 210095, Jiangsu, China.

2Central Agricultural Research Institute, Suakoko, Bong County, Liberia.

Accepted 4 July, 2023

Abstract

Rice blast caused by Magnaporthe grisea, frequently affects rice in the world. This research is intended to screen biological control agents for controlling M. grisea, referencing the study biological control agents testing approaches, since biological control is an environmentally friendly plant disease controlling approach. 710 bacterial isolates were discovered from rice tissues, of which hopeful biological control scores were discovered referencing their abilities in antagonism inhibition and secreting extracellular hydrolytic enzyme. Biological control discovery against M. grisea were experimented on 35 bacterial strains with hopeful biological control characteristic examining through amplified ribosomal DNA restriction analysis (ARDRA) and BOX analysis on isolates with high assessment scores. Five biological control agents (BCAs) with protection efficacy of more than 40% in greenhouse and field experiment were discovered. Pantoea ananatis HS-8 and Bacillus cereus DL-7 performed well in greenhouse experiment, and field test respectively. In general, correlation coefficient is 0.95 between assessment scores of 35 experimented BCAs and correlation coefficient between antagonism test and biological control efficacy show 0.72 against M. grisea. Biological control efficacies results in greenhouse and field experiments showed positive correlation with assessment scores, proposing that the BCAs evaluating and screening method set-up is reference for screening BCAs for controlling M. grisea.

Key words: Biological control agents (BCAs), biological control efficacy, extracellular metabolites, Magnaporthy grisea.