Two Distinct Genotypes of Spissistilus festinus (Say, 1830) (Hemiptera, Membracidae) in the United States Revealed by Phylogenetic and Morphological Analyses

Abstract

Spissistilus festinus (Say, 1830) (Hemiptera: Membracidae) is a frequent pest of leguminous crops in the Southern United States, and a vector of grapevine red blotch virus. There is currently no information on the genetic diversity of S. festinus. In this study, populations of S. festinus were collected in 2015–2017 from various crops and geographic locations in the United States, and fragments of the mitochondrial cytochrome C oxidase 1 (mt-COI) gene and the nuclear internal transcribed spacer 2 (ITS2) region were characterized by polymerase chain reaction and sequencing. Maximum-likelihood and Bayesian analyses of the mt-COI and ITS2 sequences yielded similar phylogenetic tree topologies, revealing two distinct genetic S. festinus lineages with all of the specimens from California comprising one phylogenetic clade, alongside a single GenBank entry from Arizona, and all specimens from the Southeastern United States comprising a statistically-supported distinct clade, regardless of host and year of collection. The mt-COI gene fragment showed up to 10.8% genetic distance between the two phylogenetic clades. These results suggest the existence of two genotypes within S. festinus in the United States. The only distinct morphological trait between the two genotypes was a less elevated pronotum in the representative specimens from California, compared to the representative specimens from the Southeastern United States. Since this phenotypic feature is inconspicuous, a diagnostic polymerase chain reaction targeting a variable region of the mt-COI fragment was developed to reliably distinguish between the specimens of the two genotypes of S. festinus and to facilitate their specific identification.

Mitochondrial COI Sequence Variations within and among Geographic Samples of the Hemp Pest Psylliodes attenuata from China

“…Instead, the observed haplotype sharing among fields located thousands of kilometers apart was likely due to incomplete lineage sorting and/or recent anthropogenic activities such as human travel and trade. Indeed, anthropogenic activities have been found to impact the distributions of a variety of plant pathogens and pests [ 15 , 19 , 20 , 34 , 35 , 36 ]. Even for the Yunnan population of P. attenuata , where no haplotype was found shared with those from other geographic areas, the Yunnan haplotypes were found closely related to those in other regions separated by one or a few mutations, consistent with their recent shared histories.…”

“…For example, at the above-species level, DNA sequence variations at COI locus have been used to assess systematics and taxonomy of insects in Pseudococcidae [ 18 ] and Lepidoptera [ 19 ]. Furthermore, COI sequences have been used to investigate the invasion history of the sirex woodwasp Sirex noctilio populations in China [ 15 ] and to identify the genotypes of three-cornered alfalfa hopper Spissistilus festinus in the United States [ 20 ].…”

Virus De La “Mancha Roja” De La Vid: Una Potencial Enfermedad en Los Viñedos De México

“…Lo anterior coincide con la dinámica de desarrollo analizada por Petro et al (2019), quienes encontraron la mayor incidencia en sus muestreos en viñedos de Cabernet Sauvignon en los meses de mayo, junio y julio; también sugieren que a la falta de vegetación residente los adultos de S. festinus migran a los doseles de las vides para alimentarse de los brotes apicales y los peciolos de las hojas a partir de junio hasta el mes de diciembre, meses en los cuales puede adquirir el GRBV. Cieniewicz et al (2020a) reportan a Spissistilus festinus como el vector de GRBV; recientemente, en EE. UU.…”

“…se identificaron dos genotipos distintos de S. festinus basados en el análisis de las secuencias obtenidas del gen mitocondrial citocromo C oxidasa 1 y la región nuclear ITS2. Con lo anterior, se demostró que la única característica morfológica distintiva entre los genotipos colectados en California y en el sureste de los Estados Unidos es la elevación del pronoto; destacando la posibilidad de la existencia de dos especies crípticas (Cieniewicz et al, 2020a); de las cuales no se cuenta con evidencia contundente si ambas puedan fungir como vector del GRBV. Bahder et al (2016) realizaron ensayos para comprobar la capacidad de adquisición del virus posteriormente a la alimentación de los insectos Erythroneura elegnatula, E. variabilis, E. ziczac y S. festinus en plantas infectadas por GRBV; siendo esta última especie la que mostró una mayor eficiencia en la adquisición del virus (un 75 % de los insectos fueron positivos a la detección por PCR digital), comprobando una transmisión efectiva postinoculación a los tres meses (0.1 %), cuatro meses (0.3 %) y cinco meses (1.6 %) por S. festinus.…”

Two Distinct Genotypes of Spissistilus festinus (Say, 1830) Reproduce and Differentially Transmit Grapevine Red Blotch Virus

“…A recent study indicated that there are two distinct genotypes of S. festinus, one residing in the Southeastern (SE) United States (Alabama, Mississippi, Georgia, North Carolina, and Virginia) and one in California (CA) [18]. Genetic analyses revealed up to 10.8% sequence divergence in the mitochondrial cytochrome C oxidase 1 (mt-COI) gene between specimens of the two phylogenetic clades of S. festinus that were grouped based on sampling location.…”