Leaf Spot Diseases in Banana (Musa spp.) and their Control (in vitro)

Abstract

Banana cultivators encounter difficulties and confusion in distinguishing foliage diseases and controlling them. An experiment was conducted from January to April in 2013, in Sri Lanka focusing on Black Sigatoka, Yellow Sigatoka, Septoria and Cordana leaf spot diseases. Test series were carried out at field level to study symptom development and, at laboratory to observe isolated pathogens under microscope. Symptoms with reddish brown specks which turning black were belonged to Black Sigatoka and oval shape spots were characteristic to Septoria leaf spot disease. Brownish streaks with yellow colour halo can be used to identify Yellow Sigatoka disease and oval shape spots with characteristic concentric zonations were due to Cordana leaf spot disease. Also cylindrical shaped spores with basal scar on the apex were produced by Mycosphaerella fijiensis (Black Sigatoka disease) and it has six to eight septa. Larger, cylindrical shaped spores with eight to ten septa that were developed by M. musicola (Yellow Sigatoka disease). Spores of M. eumusae (Septoria disease) were cylindrical and straight with four to five septa. Solitary, pyriform conidia were belonged to Cordanamusae (Cordana disease). For disease control five treatm ents including Tebuconazole, Bitertatanol, Carbendazim, Chlorothalonilwere tested [in-vitro) in a CRD experimental design. Tebuconazole and Carbendazim were recorded as the most effective chemicals for Yellow Sigatoka, Black Sigatoka and Septoria leaf spot diseases.