Abstract: The form and spore yield differentia under total darkness and continuous blue light were observed in laboratory. The results showed that the continuous blue light had little affection on the growth period,while the blue photophase was between 36~96 h,and it was 20 h earlier to produce spore than darkness and the yield of spore increased 145.9% under blue light; Pilot tests were experimented to prove the conclusion,and the yield of spore increased 36.8% under blue light. The spore rate of survival under total darkness and continuous blue light was no difference.

Key words: blue light, Paecilomyces lilacinus, form differentia, spore yield