Characterisation of Foliar Diseases of Plantain (Musa paradisiaca) in Delta State, South South Nigeria

Plantain (Musa paradisiaca) is a vital food crop and income source for farming households in Delta State, where its production underpins rural livelihoods in both upland and lowland agroecological settings. Foliar diseases have been widely reported across plantain-growing communities in the state and are believed to contribute significantly to reduced bunch weights and poor market quality. This study characterised the major foliar diseases occurring on plantain in six farming communities across Delta State. Field observations and sample collections were carried out during the 2023 growing season, targeting farms in three local government areas representing distinct agroecological conditions. Symptomatic leaf materials were examined in the laboratory, and pathogenic fungi isolated and identified based on morphological characters and sequence analysis of the internal transcribed spacer region. Black Sigatoka (Mycosphaerella fijiensis) and Yellow Sigatoka (M. musicola) were identified as the predominant causal agents, with Black Sigatoka more prevalent in lowland humid zones. The mean disease index for Black Sigatoka reached 62 percent in severely affected farms, with significant reductions in functional leaf area observed in late-season plantings. Farmers primarily applied mineral oil and copper fungicide mixtures but did so without observing recommended application intervals. The study stresses the need for improved management calendars, the introduction of tolerant Musa hybrids, and strengthened monitoring capacity in the South South zone. Keywords: plantain, Black Sigatoka, Mycosphaerella fijiensis, Delta State, foliar disease.