The complete mitochondrial genome of the cigarette beetle, Lasioderma serricorne (Coleoptera: Anobiidae)

The investigation of intraspecific characteristics and comparative analyses of the complete mitochondrial genome of Stegobium paniceum (Linnaeus, 1758) (Coleoptera: Ptinidae) assembled from public NGS raw reads of the black truffle, Tuber melanosporum

Due to the rapid development of NGS technologies, a huge amount of NGS raw reads have been accumulated in public repositories, such as the Short Read Archive of NCBI. We successfully rescued the complete mitochondrial genome of Stegobium paniceum, a drug store beetle, from public NGS raw reads of truffle generated from the whole genome project. The circular mitogenome of S. paniceum is 15,474 bp long including 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNAs, and a single large non-coding region of 803 bp. Intraspecific transfer RNAs structure and sequence variations were investigated and simple sequence repeats identified from three S. paniceum mitochondrial genomes were compared showing their diversities as fundamental data to utilize them in various aspects including developing efficient molecular markers in the family, Ptinidae. Phylogenetic analysis of 23 Bostrichoidea mitochondrial genomes presented better species identification based on phylogenetic analyses and the optimal options for constructing phylogenetic trees based on Bostrichoidea mitochondrial genomes. Our results present not only utilization of public NGS raw read sequences but also intraspecific features of S. paniceum mitochondrial genomes and comparative analysis of Bostrichoidea mitochondrial genomes in various aspects.

RNA interference-mediated control of cigarette beetle, Lasioderma serricorne

The cigarette beetle (CB; Lasioderma serricorne) is a pest on many stored products including tobacco. Fumigation is the common control method currently used. However, the options for controlling this pest are limited, due to resistance issues and phasing out of currently used chemical insecticides. Here, we evaluated RNA interference (RNAi) as a potential method for controlling the CB. RNA isolated from different stages was sequenced and assembled into a transcriptome. The CB RNA sequences showed the highest homology with those in the red flour beetle, Tribolium castaneum. Orthologs of proteins known to function in RNAi pathway were identified in the CB transcriptome, suggesting that RNAi may work well in this insect. Also, ³² P-labeled double-stranded RNA (dsRNA) injected into CB larvae and adults was processed to small interference RNAs. We selected 12 genes that were shown to be the effective RNAi targets in T. castaneum and other insects and identified orthologs of them in the CB by searching its transcriptome. Injection of dsRNA targeting genes coding for GAWKY, Kinesin, Sec23, SNF7, and 26S proteasome subunit 6B into the CB larvae caused 100% mortality. Feeding dsRNA targeting SNF7 and 26S proteasome subunit 6B by sucrose droplet assay induced more than 90% mortality, which is 1.8 times higher than the mortality induced by dsGFP control (53%). These data demonstrate an efficient RNAi response in CB, suggesting that RNAi could be developed as an efficient method to control this pest.

Biology, Ecology, and Control of Lasioderma serricorne (F.) (Coleoptera: Anobiidae): A Review

The cigarette beetle, Lasioderma serricorne(F.) (Coleoptera: Anobiidae), is an important pest in the food and tobacco industry in many regions of the world. Despite a great deal of research, control of this pest still relies on the use of phosphine fumigation, which is becoming less effective as the insect develops resistance to this compound. In addition, series of other nonchemical methods used to control the insect have given mixed and irregular results. This review summarizes and discusses information on important aspects of the biology and ecology of the cigarette beetle, and its control. The topics covered include a taxonomic discussion of the cigarette beetle, which includes a discussion of other anobiid species of economic importance. The mating behavior of the insect and conditions favorable for pest development were described. The review also includes a discussion of the life stages of the insect, its feeding habit, and economic damage. Important aspects of its chemical ecology and a discussion on the association between this species and its microorganisms, and major natural enemies, were presented. A summary of its flight behavior, including the factors governing flight initiation and temporal and seasonal flight activity were reviewed. Finally, the control methods currently used in the management of the insect were described. The review also identifies potential areas of further research on L. serricorne and gives an analysis of the control methods worthy of further investigation in the search for practical and sustainable methods for the management of this pest.