Simultaneous infection of Leptodelphax maculigera (Hemiptera: Delphacidae) by maize rayado fino virus (MRFV) and maize bushy stunt phytoplasma (MPSP) detected in Rio Grande do Sul, Brazil

Abstract

The corn stunt disease is a major threat to maize production in Brazil. In addition to the more common insect vector Dalbulus maidis (Hemiptera: Cicadellidae), the African species Leptodelphax maculigera (Hemiptera: Delphacidae) was recently found in the Brazilian states of Goiás, Paraná and Santa Catarina, raising concern regarding its potential ability to transmit stunt pathogens. We confirmed the presence of L. maculigera in the state of Rio Grande do Sul by conducting a population survey with yellow sticky traps and light traps in three different sites, although it corresponded to only 2.3% of the D. maidis population captured during the same period. Molecular analysis via RT-qPCR multiplex confirmed the simultaneous infection of L. maculigera by two corn stunt pathogens—Maize rayado fino virus (MRFV) and Maize bushy stunt phytoplasma (MBSP)—in 76.9% of the samples, while the remaining 23.1% showed single infection by MRFV. The confirmation of infectivity by two stunt pathogens in L. maculigera will aid in the outlining of management strategies for this insect vector.