Nuclear polyhedrosis virus DNA identification and first evaluation against Strawberry pest, Pentodon algerinum (Coleoptera: Scarabaeidae)

Abstract

In Egypt, The white grub, Pentodon algerinum (Coleoptera: Scarabaeidae) damages various economic important plants recently strawberry. This study aimed to DNA identification and first evaluation of the Spodopteda littoralis Nuclear polyhedrosis virus (SpliNPV) and Pentodon algerinum Nuclear polyhedrosis virus (PNPV) against Pentodon algerinum third instar larvae in the laboratory to find successful safe alternative control method against this pest. Bioassay was made by two experiments, one used five SpliNPV concentrations, 6.7X10 6 , 3.11X10 7 , 1.1X10 8 , 3.64X10 9 and 3.64X10 10 Polyhedral inclusion bodies (PIB/ml) achieved 80, 100, 100, 80 & 90% mortality respectively during thirteen days. Another experiment used four PNPV concentrations, 8.2x10 7 , 8.2x 10 8 , 2.6x10 9 and 8.2x10 9 PIB/ml caused 100, 70, 67 & 72.7% mortality respectively during ten days. SpliNPV Lethal concentrations LC50 6.2x10 14 & LC90 8.9x10 9 PIB/ml were more than PNPV LC50 2.8X10 9 & LC90 1.8X10 8 PIB/ml. Thus PNPV and SpliNPV were effective against Pentodon larvae but PNPV was effective and specific more than SpliNPV. DNA of SpliNPV and PNPV was identified by RAPD PCR using four RAPD primers, Operon A9, A20, B17 & B7 (Operon Technologies, Inc., Alameda, CA, USA) using automated (Bio Rad, USA) thermal cycler. Total 33 bands were produced including 24 PNPV bands with molecular weights between 152-1204 base pairs (bp) included between resulted 9 SpliNPV bands having molecular weights between 138-1767 bp. Therefore PNPV is similar to SpliNPV in almost its DNA sites and also is a polymorphic copy from SpliNPV. Thus PNPV and SpliNPV can be recommended against this pest.