Use of DNA Barcodes to Identify Invasive ArmywormSpodopteraSpecies in Florida

Abstract

A critical component for sustaining adequate food production is the protection of local agriculture from invasive pest insects. Essential to this goal is the ability to accurately distinguish foreign from closely related domestic species, a process that has traditionally required identification using diagnostic morphological “keys” that can be both subtle and labor-intensive. This is the case for the Lepidopteran group of insects represented by Spodoptera, a genus of Noctuidae “armyworm” moths that includes several important agricultural pests. Two of the most destructive species, Spodoptera littoralis (Boisduval) (Lepidoptera: Noctuidae) and S. litura (F.) are not yet established in North America. To facilitate the monitoring for these pests, the feasibility of using DNA barcoding methodology for distinguishing between domestic and foreign Spodoptera species was tested. A DNA barcoding database was derived for a subset of Spodoptera species native to Florida, with an emphasis on those attracted to pheromone blends developed for S. litura or S. littoralis. These were then compared to the barcode sequences of S. litura collected from Taiwan and S. littoralis from Portugal. Consistent discrimination of the different species was obtained with phenetic relationships produced that were generally in agreement with phylogenetic studies using morphological characteristics. The data presented here indicate that DNA barcoding has the potential to be an efficient and accurate supplement to morphological methods for the identification of invasive Spodoptera pests in North America.

DNA barcodes for bio-surveillance: regulated and economically important arthropod plant pests

“…For example, aside from enabling the early detection of invasive species (Onah et al 2015), DNA barcoding can reveal source regions (Bellis et al 2015) and introduction patterns (Blacket et al 2015). Nagoshi et al (2011) used it to moni-tor introductions of the invasive armyworm species, Spodoptera litura and S. littoralis, into Florida, while Tyagi et al (2015) and Wei et al (2010) detected the first invasions of Thrips parvispinus and Echinothrips americanus in India and China, repectively. In a similar fashion, DNA barcoding differentiated Heliothis armigera from the native H. zea, revealing the spread of the former species after its introduction into Brazil (Mastrangelo et al 2014).…”

Genetic Characterization of Fall Armyworm (Lepidoptera: Noctuidae) Host Strains in Argentina

“…The unrooted phylogenetic tree was derived using the Tamura-Nei genetic distance model (Tamura and Nei 1993) and unweighted pair-group method with arithmetic average analysis (Sneath and Sokal 1973), with conÞdence assessed by bootstrapping at 1,000ϫ repetition. Spodoptera species are represented by consensus sequences derived from Nagoshi et al (2011). Only conÞdence values above 75% are indicated and nodes below 70% are collapsed.…”

Pathogenicity of indigenous soil isolate of Bacillus thuringiensis to Helicoverpa armigera Hübner 1809 (Lepidoptera: Noctuidae)

“…These species have well-adapted different agro-ecological zones around the globe from Asia to Africa to Europe (Zhang et al 2015). They are polyphagous pests with a wide range of host plants including: cotton, maize, gram, sesame, okra, tomato, potato, and many other fruit and vegetable crops (Aggarwal et al 2006;Nagoshi et al 2011). Nevertheless, due to blind and extensive use of pesticides, these and other lepidopterous pest species have developed resistance to almost all groups of pesticides including organochlorines, organophosphates, carbamates, and pyrethroids (Kranthi et al 2001).…”