Investigation on the insecticidal potential of Aspergillus japonicas D-19 isolated from the Tibetan plateau against Locusta migratoria manilensis (Meyen) (Orthoptera: Acrididae)

Abstract:

By using dilution coating method a fungus D3-19 with insecticidal activity against locusts was isolated from soil of the Qinghai-Tibet Plateau. By the morphological observation and ITS sequence analysis, D3-19 was preliminary identification as A.japonicas. Indoor bioassay results showed that both fermentation liquor and conidial suspension of A.japonicas D3-19 had insecticidal activity against L. migratoria. For 96 and 144 h of treatment, The corrected mortalities of the A. japonicas D3-19 fermentation liquor against L.migratoriawere 86.67% and 100%, respectively. Meanwhile, the LC 50 value of L.migratoria to the A. japonicas D3-19 conidia suspension was 3.42×10 5 conidia/mL. The result showed that, 3×10 8 conidia/mL conidial suspension of A. japonicas D3-19 had insecticidal activity against all life stages of L. migratoria, and the LT 50 (median lethal time) values of emerging adults, fourth to fifth instars, third instars larvae, and second instars larvae were 155 h, 104.8 h, 54.6 h, and 30.6 h, respectively.