_____________________________________________________________________________________________________ *Corresponding author: E-mail: lihx@gsau.edu.cn; Asian Research Journal of Agriculture 15(2): 27-44, 2022; Article no.ARJA.84800 ISSN: 2456-561X Mechanism of Antagonistic Bioagents in Controlling Root-Knot Nematodes (Meloidogyne sp.): A Review Thomas Afriyie Boakye a , Dominic Kwadwo Anning b , Huixia Li a* , Richard Osei a , Solomon Boamah a and Samuel Anim c a College of Plant Protection, Gansu Agricultural University/ Biocontrol Engineering Laboratory of Crop Disease and Pests of Gansu Province, Lanzhou-730070, China. b Council for Scientific and Industrial Research – Oil Palm Research Institute, P. O. Box- 74, Kade, Ghana. c Department of Agriculture, Sekyere Central District, P. O. Box NU 64, Nsuta, Ashanti, Ghana. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/ARJA/2022/v15i230153 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/84800 Received 15 December 2021 Accepted 19 February 2022 Published 20 February 2022 ABSTRACT Root-knot nematodes are among the most significant pathogenic organisms due to their global distribution, capacity for destruction, and economic importance. Antagonistic bioagents are more effective alternative to synthetic pesticides in the suppression of root-knot nematodes. Bioagents reduce the use of synthetic chemicals, which are hazardous to both humans and the environment. Despite this, some bioagents, such as fungi and bacteria have unknown mechanisms. This review discusses the nematophagous bacteria and fungi that have been discovered so far, including Pochonia, Trichoderma sp., Pseudomonas sp., and Bacillus sp., with an overview of the current advances in research regarding their molecular and biochemical control mechanisms. Biological control agents (BCAs), as valuable ecological enemies of nematode infestations, use a range of mechanisms, such as parasitism, nutrient competition, toxin production, induce systemic resistance to antibiotics, enzymes, and enhance plant health. They suppress nematodes directly, improve plant growth, and facilitate the colonization and activities of antagonistic microbes in the rhizosphere. Understanding the molecular basis of BCAs suppression mechanisms provides the basis for their future incorporation into phytopathogen or plant disease control management. This study reviews Review Article