Island-wide molecular survey targeting Pseudocercospora spp. causing Sigatoka leaf spot diseases of banana in Mauritius

The Sigatoka disease complex, caused by Pseudocercospora fijiensis, P. musae, and P. eumusae, severely impacts banana production worldwide. Although all three species have been reported in Mauritius, their distribution across the island has not been assessed. In April 2024, surveys were conducted at 43 sites across the island, and species-specific real-time PCR assays were used for pathogen identification. P. eumusae was the predominant species, detected at all sites (88% prevalence). P. fijiensis occurred at lower frequency (11%) but was present in all regions, confirming its rapid expansion since its first detection in 2022. P. musae was rare (1%) and confined to three sites across three regions. Coexistence between P. eumusae and P. fijiensis was observed at eleven sites, while all three species co-occurred at three. These findings provide the first island-wide molecular assessment of three Pseudocercospora spp. in Mauritius and demonstrate the continuing spread of P. fijiensis, underscoring the need for sustained monitoring and management strategies.