Interaction between Fusarium oxysporum f. sp. cubense and Radopholus similis can lead to changes in the resistance of banana cultivars to Fusarium wilt

Fusarium oxysporum f. sp. cubense (Foc) causes Panama disease or Fusarium wilt of bananas. The association between soil-inhabiting fungi and nematodes can increase the severity of symptoms and suppress the resistance of plants to diseases. In this study, the interaction between Foc race 1 and Radopholus similis, a burrowing nematode that parasitizes banana plants, was analyzed using one moderately susceptible cultivar and seven resistant cultivars of banana. Two Foc isolates that differed in virulence were tested. The analyses of symptoms and stained fungal structures in the roots demonstrated that R. similis interacting with Foc in different inoculation sequences caused changes in symptom severity and the resistance pattern to Foc isolate 0801 (race 1) in cultivars ‘Terra Maranhão’, ‘BRS Pacovan Ken’, ‘BRS Vitória’, and ‘BRS Platina’. The data generated in this study have relevant implications for banana breeding programs in the classification of cultivars for durable resistance to Fusarium wilt and for understanding pathogen interactions during occurrence of the disease.