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Abstract Dasychira pudibunda is a defoliating forest pest, and it caused an outbreak in oriental beech forests in Bursa, Turkey, in 2019. Examination of collected dead larvae revealed that the body contents were liquefied as in baculovirus infections. Transmission electron microscopy showed that the isolate had many nucleocapsids in an envelope in the occlusion bodies. The isolate was named Dasychira pudibunda nucleopolyhedrovirus-T1 (DapuNPV-T1). Host range studies showed that DapuNPV-T1 was virulent to lymantriid insects. The fact that few pests were found in the surveys conducted in the region between 2020-2022 shows that the epidemic was suppressed seriously by DapuNPV-T1 in 2019. [ABSTRACT FROM AUTHOR]

The fall webworm (Hyphantria cunea) impacts a wide variety of crops and cultivated broadleaf plant species. The pest is native to North America, was introduced to Europe and has since spread further as far as central Asia. Despite several attempts to control its distribution, the pest continues to spread causing damage all over the world. A naturally occurring baculovirus, Hyphantria cunea granulovirus (HycuGV-Hc1), isolated from the larvae of H. cunea in Turkey appears to have a potential as microbial control agent against this pest. In this report we describe the complete genome sequence and organization of the granulovirus isolate (HycuGV-Hc1) that infects the larval stages and compare it to other baculovirus genomes. The HycuGV-Hc1 genome is a circular double-stranded DNA of 114,825 bp in size with a nucleotide distribution of 39.3% G + C. Bioinformatics analysis predicted 132 putative open reading frames of (ORFs) ≥ 150 nucleotides. There are 24 ORFs with unknown function. Seven homologous repeated regions (hr s) and two bro genes (bro -1 and bro -2) were identified in the genome. Comparison to other baculovirus genomes, HycuGV-Hc1 revealed some differences in gene content and organization. Gene parity plots and phylogenetics confirmed that HycuGV-Hc1 is a Betabaculovirus and is closely related to Plutella xylostella granulovirus. This study expands our knowledge on the genetic variation of HycuGV isolates and provides further novel knowledge on the nature of granuloviruses. • The HycuGV-Hc1 DNA genome has 114,825 bp, GC content of 39.3% and 132 putative ORFs. • Seven homologous regions (hrs) were identified in the genome. • The phylogenetic tree showed that HycuGV-Hc1 to be closely related to the PlxyGV. • HycuGV-Hc1 is infective for H. cunea larvae which impacts a wide variety of crops. [ABSTRACT FROM AUTHOR]

The gypsy moth (Lymantria dispar L., Lepidoptera: Lymantriidae) is one of the most serious pest of various forestal, food and industrial crops worldwide. We have characterized a new Lymantria dispar nucleopolyhedrovirus (LdMNPV-T4) variant, which was isolated from dead L. dispar larvae in Turkey. Scanning electron microscope observations showed that the polyhedral occlusion bodies (OBs) of the LdMNPV-T4 were irregularly shaped. Transmission electron microscopy revealed that OBs of LdMNPV-T4 were occupied with several virions in which multiple nucleocapsids packaged by viral envelope. Restriction analysis of the LdMNPV-T4 DNA purified from the viral inclusion bodies yielded BamHI, BglII, EcoRI and HindIII fragments. The mean size estimated for the complete LdMNPV-T4 genome was calculated to be 163.3 kb. Phylogenetic analysis of amplified polh, lef-8 and lef-9 sequences showed its relation to the other NPVs from Lymantria species. Mortality values of the LdMNPV-T4 at four different concentrations against third instar larvae of L. dispar ranged from 45% to 88%. These results suggest that LdMNPV-T4 isolated from Turkey is a promising microbial control agent to be utilized for the biological control of L. dispar. [ABSTRACT FROM AUTHOR]