Technique for establishing pathogenic behaviour of Phytophthora colocasiae (rac.) causing leaf blight of colocasia

A new technique was devised for establishing pathogenic behavior of Phytophthora colocasiae on detached plant parts of colocasia in the laboratory as well as in pot culture. Results showed that incubation period was shorter in inoculated leaves (23.39 days) and stalks (108.70 days) and was highest in corms (220.20 days) under laboratory conditions. In pot culture study, the incubation period was shorter on new leaves, stalks and corms in comparison to older leaves, stalks and corms.