March 4, 2025 | Journal of Fungi |
The diversity and identity of Fusarium oxysporum f. sp. cubense (Foc), which causes Fusarium wilt in bananas, were examined in a study conducted by researchers from Assam Agricultural University and the ICAR-Indian Institute of Horticultural Research, India. This disease poses a major threat to banana cultivation globally and significantly impacts the production of the Malbhog variety (AAB group) in northeastern India.
The study involved isolating 25 Foc strains from wilt-affected Malbhog banana plantations. Pathogenicity tests confirmed their role as causal agents of the disease. Morphological and cultural characterization of the isolates revealed significant variability in colony appearance, pigmentation, chlamydospore presence, and conidial dimensions. Molecular identification using race-specific primers indicated all isolates belonged to Race 1 of Foc, with no detection of the more virulent Tropical Race 4.
To assess genetic diversity, ISSR (Inter Simple Sequence Repeat) markers were used, revealing five major genetic clusters among the isolates. High levels of polymorphism were observed, with 96% of the genetic diversity present within populations, as supported by Nei’s genetic diversity, Shannon’s information index, and AMOVA results.
These findings offer valuable insight into the population structure of Foc affecting Malbhog bananas and support the development of targeted disease management strategies to mitigate the risk of Fusarium wilt epidemics in the region.
