Comparison of two culture medium of Metarhizium pingshaense SG-A and its pathogenic activity against Diaphania indica(Saunders)
In order to compare the biological characteristics and pathogenicity of Metarhizium pingshaense SG-A on two media,the size of colony,sporulation yield and spore germination rate of M.pingshaense SG-A on potato glucose AGAR medium(PDA)and sabouraud dextrose agar with yeast extract(SDAY)were measured after 14 days.The pathogenicity of M.pingshaense SG-A against different insect states of Diaphania indica(Saunders)was determined by dip method.The biological characteristics on different media and pathogenicity to D.indica of M.pingshaense SG-A were measured.The results showed that the spore production of M.pingshaense SG-A after 14 days of PDA culture was significantly higher than that of SDAY culture medium,and there was no significant difference in colony size and spore germination rate.M.pingshaense SG-A showed high pathogenicity against the 2nd and 4th instar larvae and pupae,and the pupae had the high-est pathogenicity.The LC50 was 1.93 × 105 conidia·mL-1,and the cumulative mortality of pupae was 90％when the spore concentration was 1×108 conidia·mL-1.The cumulative mortality of 2nd instar and 4th instar larvae also reached 86.67％and 83.33％,respectively,but the death time of 4th instar larvae was earlier than that of pupa and 2nd instar nymphs,and the LT50 was 2.60 days.In conclusion,M.pingshaense SG-A has high pathogenicity against each species of D.indica,which can further explore its biocontrol potential.
万方数据
维普
