Black sigatoka

Black Sigatoka leaf spots begin as minute (1mm) reddish-brown flecks on the lower leaf surface that gradually increase in size to form dark linear streaks (4–12mm) parallel to the leaf veins that are visible on both leaf surfaces. As the streaks mature they expand, becoming oval spots often with a distinctive yellow halo. As the lesions mature further they become sunken and the centre turns grey. In susceptible cultivars, high levels of disease can cause large areas of the leaf surface to die.