Citrus anthracnose

Citrus anthracnose

    Causal organism: Colletotrichum gloeosporioides
    Symptoms
    • The disease causes defoliation and tip drying of twigs, called whither tip.
    • Shedding of leaves and dieback of twigs.
    • Acervuli appear as black dots on the dead twigs. Light green spots appear which later turn brown.
    • The pathogen also infects the stem-end of immature fruits causing fruit drop.
    • In severe cases branches also show die back symptoms.
    Etiology
    • Septate mycelia, asexual fruiting body is the –acervulus and setae are present
    • Primary source of inoculum: Dormant mycelia
    • Secondary source of inoculum: Conidia produced in Acervulus
    Epidemiology
    • Disease is favoured by warm weather at temperature of 30-32oC, RH 80-85%, cloudy weather and presence of susceptible host.
    Management
    • Collect affected leaves and burn them.
    • Avoid excess N application.
    • Irrigation during summer is required.
    • Chemicals: Carbendazim @-1.5gm/lt and Benomyl- @1gm/lt

Last modified: Friday, 20 January 2012, 1:24 PM