3.Pathogenicity Test (Koch's postulate)
Pathogenicity of the fungal isolate was tested on plants of Ca. assamicum by infecting the leaves with sporulating culture. The spore suspension was prepared by adding 2 ml of sterilized water to a PDA plate and the conidia were dislodged with a sterile glass rod. To infect the leaves,200 µl of the spore suspension was deposited carefully over each leaf. The inoculations were repeated for three consecutive days and the plants were kept in a growth chamber(LebTech LCG-5201;temperature 28+0.5 c; RH 95%;photoperiod 12 h; light 8500 Iux).