Vertwillium Wilt of Polyalthia longifolia - a New Disease Report from India

Verticillium dahliae was identified as a pathogen causing wilt disease of Polyalthia longifolia. It was isolated from the infected ischolar_mains of the seedlings collected from Central Forest Nursery of Imphal, Manipur, India. Four fungicides viz. Bavistin 50% WP, Dithane M-45, Dithane Z-78 and Fytolan 50% WP were screened against the pathogen at different concentrations using poison food technique in vitro and then in field-conditions using soil drenching technique. The results revealed that Bavistin 50% WP was most effective at 75 ppm with 100% growth inhibition followed by Dithane M-45, Dithane Z-78 and minimum efficacy was observed by Fytolan 50% WP with 31.27% growth inhibition in laboratory conditions. All selected fungicides were evaluated against pathogen in field conditions at 0.1% and 0.2 % concentrations. Bavistin 50% WP was found to be the most effective at 0.2% concentration. Thus the present study recommends soil drenching with Bavistin 50% WP at aminimal concentration of 0.2% for management of the disease.