Cultural and Morphological Characterization of Causal Agentsof Twister Disease of Onion

In recent years, twister disease of onion has become epidemic in coastal tract and other onion growing districts of Karnataka. Infected samples which are collected from different locations during survey were subjected to identification and were characterized for morphological and cultural characters to assess the diversity of the pathogens. This disease C.gloeosporioides and F. oxysporum are causing heavy yield loss The pathogens causing have been identified C. gloeosporioides varies with color cream, pink and grey where as C. acutatum color pink, brown, yellow and cream and regular to irregular margin and fluffy course to smooth growth with or without sectoring producing good sporulation where as F. oxysporum had white, cream and pink color exhibiting their variability.