Preparation of T. harzianum T9 inoculum
Isolate T9 of T. harzianum, obtained from the Department of
Plant Pathology, Khon Kaen University (KKU), Khon Kaen, Thailand,
was used in the trials. The isolate was cultured on potato dextrose
agar (PDA) in an incubator at 25 2 C. After 3 days of incubation,
mycelium of T. harzianum T9 from PDA in petri dishes was cut using
a 0.5-cm-diameter cork borer and transferred to sterilized sorghum
seeds in bottles containing 30 g of steam-sterilized sorghum grains.
The bottles were regularly shaken to facilitate thorough colonization
by the fungus. After 10 days of incubation, the inoculum was
ready to use.