1.2.1 Preparation of non-dormant chlamydospore
The agar containing mycelium grown on PDA was separated into 6~8 even small rounds with a sterilized hole punch (aperture 5×5 mm) and inoculated in the above triangular flask containing Sandburg’s liquid culture medium. The flask was shocked at 28 ℃ at 200 r/min for 72 h and the culture was stopped. 10 mL of the culture containing mycelium was inoculated into a triangle flask containing 1000 mL of 200 g grains [28]. Then the culture was placed in an incubator at 28 ℃ for 21 days. When more mycelium grew on the grain and yellow powder culture was observed by naked eye, it was proved that more chlamydospore had been produced, and the culture was terminated. An appropriate amount of 0.05% sterilized Tweene-80 solution was added to the triangular flask, and the solution was swirled for 1-2 min, then mycelium and spores were washed off the grains, and the crude spore suspension was collected and placed in ultrasonic cell pulverization instrument (SCO-2500, Shanghai Shengyan Ultrasonic Instrument Co., LTD.), and subjected to ultrasonic treatment for 5 min at 150W and 20 KHZ. At an interval of 30 s, the spore suspension was filtered through a 300-mesh copper screen, the filtrate was centrifuged at 1000 r/min for 5 min, and then washed with sterilized distilled water for 3 times. The sediment (i.e. chlamydospore) was suspended with sterilized distilled water and counted with a blood cell count plate. Finally, the concentration of the spore suspension was adjusted with distilled water to about 1×104 spores /mL for further use.