Entomotoxic proteins of Beauveria bassiana Bals. (Vuil.) and their virulence against two cotton insect pests

Abstract

Entomopathogenic fungi are widely used as biocontrol agents against several agricultural pests. Among them, Beauveria bassiana is considered the important one against insect and other arthropod pests. The entomotoxic proteins of B. bassiana were extracted by Sephadex G-25 column, and fractionated using HPLC (BBI, BBII and BBIII) and tested against two hemipteran insect pests i.e., Dysdercus cingulatus Fab. and Phenacoccus solenopsis Tinsely (Hemiptera: Pseudococcidae). Results indicated that protein content was higher in fraction BBII than BBI and BBIII. The vibration frequency in FT-IR obtained with a range of 1650 to 1580 cm−1. Bioassays of fractions (I, II and III) reveal that BBII was highly virulent against third nymphal instar of D. cingulatus (LC50 = 800.2 ppm) and adults of P. solenopsis adult (LC50 = 713.3 ppm). Considering the high virulence of BBII subjected to SDS-PAGE, HPLC and MALDI-TOF analyses. Analyses reveals the presence of 174 kDa and designated as BBF2. These results concluded that the entomotoxic protein of B. bassiana can be utilized for management of these investigated hemipreran pests. Further investigations are necessary for the field application of this entomotoxin against these pests or other insect pests. These results also could be helpful for establishing novel biotechnological uses for this fungus.

Keywords

• Beauveria bassiana
• Entomotoxin
• Characterization
• Insecticidal activity