DNA barcoding of Bradysia (Diptera: Sciaridae) for detection of the immature stages on agricultural crops

Abstract

We investigated the usefulness of mitochondrial cytochrome c oxidase (COI) DNA barcoding of the genus Bradysia for the detection of immature stages and cryptic species complex. Although the larvae of some species in this genus are agricultural pests, immature stages are rarely identified due to the lack of key morphological characteristics. We constructed partial sequences of the COI gene for 25 species of Bradysia as a first step towards a DNA barcode. Using these data, Bradysia impatiens, B. procera and B. peraffinis were identified from larval specimens collected, respectively, from paprika, ginseng and oak sawdust beds used for cultivating shiitake. Our findings reveal a complex of three species within the B. tilicola group. These species were all identified as important pest B. ocellaris based on the morphology of male genital structures; however, the interspecific genetic divergence of the COI region was significantly greater (16.1–19.4%) than the intraspecific variation in each species. Therefore, B. ocellaris may consist of at least three species. The results demonstrate that COI DNA barcodes are useful for Bradysia species identification.

The application of rapid evaporative ionization mass spectrometry in the analysis of Drosophila species—a potential new tool in entomology

“…These include cuticular hydrocarbon analysis [26], immunological [27] or protein-based assays [28] as well as mass spectrometry-based applications such as matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) [29]. However, DNA barcoding is often the method of choice, as it can handle a variety of sample conditions, developmental stages and cover a large number of species and taxa [30][31][32]. In routine identification or monitoring actions, identifying unknowns is not the only challenge.…”

DNA barcoding for biosecurity: case studies from the UK plant protection program

“…Molecular (as opposed to morphological) identification strategies may be needed for a number of reasons. Most commonly, key diagnostic structures may be damaged or missing, or there is no primary description or morphological key to the taxa or life stage being examined (Shin et al 2015). Another common application is to expedite identification following detection.…”

Effects of short‐term heat stress on the growth and development of Bradysia cellarum and Bradysia impatiens

“…Bradysia impatiens Johansen, 1912 (= Bradysia difformis Frey, 1948), commonly known as the fungus gnat maggot, is considered an important pest of greenhouse crops, nursery bed crops, house crops and mushrooms (Hellqvist, ; Jagdale, Casey, Canas, & Grewal, ; Mohrig, Heller, Hippa, Vilkamaa, & Menzel, ; Santos & Zanuncio, ; Shin et al, ; White, Smith, & Menzel, ). Bradysia impatiens is reported to be an introduced species in South African (Hurley, Govender, Coutinho, Wingfield, & Wingfield, ; Hurley, Slippers, et al, ) and was first recorded on edible fungi in Yunnan Province, China, in 2009 (Shen et al, ).…”

“…Studies on feeding behaviours, occurrence regulations and chemical control strategies for both insects have been reported in Shandong, Hebei, Beijing, Tianjin and other provinces of China (Mei et al, ). Several studies have also investigated the genetic diversity and molecular characteristics of the two species (Chen et al, ; Tang et al, ; Hurley, Slippers, & Wingfield, ; Shin, Jung, & Menzel, ; Shin et al, ).…”