Project description:Invertebrate iridescent virus 6 (IIV6) was evaluated for mode of transmission and ability to cause infection in the root weevil, Diaprepes abbreviatus (L.). This is the first evidence of IIV6 infection in D. abbreviatus, which caused both patent and sub-lethal covert infections in both larvae and adults. Adults and larvae were successfully infected with IIV6 by puncture, injection and per os. Transmission of IIV6 was demonstrated between infected and healthy individuals regardless of gender. Virus was detected in egg masses produced by virus-infected females suggesting IIV6 is transmitted transovarially. Virus particles were observed in the cytoplasm of weevil cells, and were shown to infect fat bodies, muscle, and nerve tissues, as visualized using transmission electron microscopy. Patent infections resulted in death of individuals within 3 to 4 days post infection. Individuals with covert infections tested positive for virus infection on day 7 by polymerase chain reaction analysis. Sequencing of PCR amplicons confirmed virus infection. Discovery of new pathogens against root weevils may provide new management tools for development of control strategies based on induced epizootics. This is the first report of a virus infecting D. abbreviatus.
Project description:Calliptamus abbreviatus Ikovnnikov (Orthoptera: Acridoidea) is one of the important pests in the grasslands in northern China. The complete mitochondrial genome of this insect was sequenced. This genome is 16,615 bp long, with an AT content of 73.3%, containing 37 typical animal mitochondrial genes and an AT-rich region. All 13 PCGs share the start codon ATN, and the usual termination codons (TAA) are found from 13 protein-coding genes. All of the 22 typical animal tRNA genes were found in C. abbreviatus mt-genome, and most of the tRNAs could be folded into the classic cloverleaf secondary structure except for tRNA-Ser (AGN), which lacks the dihydrouracil (DHU) stem. The sizes of the large and small ribosomal RNA genes are 1555 and 799 bp long, respectively. The AT content of the AT-rich region is 87.0%. Phylogenetic analysis supports that the coleopteran insects from the same family cluster in the same group.
