Identification and virulence of a fungal entomopathogen strain NDBJJ-BFG to Colorado potato beetle Leptinotarsa decemlineata (Say).

YuLin D, Hui W, ZhiYan M, Liu Y, XiaoDong D, DeYing M. Journal of Plant Protection. 2018;45(4):751-758.

To screen the control potential strain to control Colorado potato beetle, Leptinotarsa decemlineata (Say), the strain NDB JJ-BFG was isolated from L. decemlineata infected by disease. The classification of the strain NDBJJ-BFG was determined with both morphological and molecular biological methods, and the LC50 and LT50 of L. decemlineata larvae were monitored using spraying and covering with soil. The strain NDBJJ-BFG was identified as Beauveria bassiana (Bals.) Vuill based on morphological characteristics and rDNAITS sequence analysis. LC50 values of the 1st instar, 2nd instar, 3rd instar and 4th instar larvae were 9.67×105, 1.51×106, 5.09×106 and 6.84×106 spores/mL, respectively. LC50 values of the pupae of spraying treatment and soil treatment were 1.43×107 spores/mL and 8.15×106 spores/mL, respectively, and LC50 values of adult were 5.08×107 spores/mL and 2.97×108 spores/mL, respectively. LT50 value increased along with larva instar increasing at the same concentration of spore suspension, and LTso value of the adult was the highest, then followed by pupae. At the same larva instar, LT50 value decreased along with the concentration of spore suspension increasing. Therefore, the strain NDBJJ-BFG exhibited high virulence to both the 1st and 2nd instar larvae of L. decemlineata, and had high potential ability for the biological control of L. decemlineata.