Abstract

Endophytic microorganisms inhabit internal plant tissues without causing apparent disease and represent an important source of biological diversity and bioactive metabolites. Aquatic plants provide unique ecological niches for microbial colonization due to fluctuating oxygen availability, high moisture levels, and complex nutrient dynamics. Nelumbo nucifera Gaertn., commonly known as sacred lotus, is an aquatic angiosperm widely distributed throughout Asia and valued for its ecological, nutritional, and medicinal importance. Recent studies indicate that this plant hosts diverse communities of fungal and bacterial endophytes with significant functional potential. The present review summarizes the diversity, biological activities, and potential applications of endophytes associated with N. nucifera. Reported fungal endophytes include genera such as Colletotrichum, Diaporthe, Fusarium, and Aspergillus, while bacterial endophytes are commonly represented by plant growth–promoting genera such as Bacillus and Pseudomonas. These microorganisms exhibit several beneficial traits including phosphate solubilization, siderophore production, ammonia production, hydrogen cyanide synthesis, and extracellular enzyme secretion. Several isolates have demonstrated antimicrobial activity against pathogenic microorganisms, including methicillin-resistant Staphylococcus aureus (MRSA). In addition, bacterial strains such as Bacillus velezensis have shown promising antagonistic activity against Fusarium oxysporum, the causal agent of lotus rot disease. Overall, endophytes associated with N. nucifera represent a valuable reservoir of bioactive compounds and beneficial microorganisms with potential applications in agriculture, medicine, and biotechnology.

Key words: Nelumbo nucifera, endophytic microorganisms, antimicrobial activity, plant growth promotion, aquatic plants