Abstract:
Paddy grains infected by brown spot disease were collected from farmers field in Batticaloa
district, during Maha 1995/96. The samples were brought to Agricultural Biology Laboratory,
Eastern University where the experiments were conducted.
In one experiment, infected seeds were surface sterilized by immersing for 2-3 mins. In 5%
sodium hypochlorite solution and placed in fungicided amended Oat Meal Agar (OMA) media
with Captan, Mancozeb and Hinosan, contained in sterile petridishes. They were incubated at
room temperature for one week in a wooden incubation chamber. In another experiment infected
seeds were soaked in solutions of the same three fungisides for six hours and placed in OMA
pour plates which were also incubated as in the first experiment. Unamended OMA medium and
untreated seeds were used as control, in the first and second experiments, respectively.
Fungicide Mancozeb completely inhibited mycelia development in paddy grains during the
experimental period. Captan significantly inhibited mycelia growth and sporulation. There was no
significant difference with respect to mycelial growth fungi, Cochliobolus Iunatus and
Cochliobolus sativus, colonies were observed in paddy grains in both.
Moncozeb appears to be the most suitable fungicide to control brown spot disease in paddy
grains. However, these fungicides are to be tested under field conditions before any conclusion is
made.