First Report and Molecular Variability of Belonolaimus longicaudatus Associated with Turfgrass in Maryland.

Abstract

Turfgrass is a crop used extensively in athletic fields and golf courses in Maryland. A soil sample collected in July 2023 from an athletic field in Baltimore County, Maryland, part of a turfgrass nematode survey, contained Belonolaimus longicaudatus. In the southeastern United States, B. longicaudatus is an economically important pathogen of warm season turfgrass. The density was four individuals/100 cm³ of soil, and no visual symptoms were observed in the bermudagrass field. Morphological features and morphometrics of males and females were consistent with B. longicaudatus and placed the Maryland population in a subclade that was geographically represented by populations from north and west Florida, Texas, and South Carolina. Sequencing of the internal transcribed spacer region ITS1 and ITS2 and 28S large ribosomal subunit D2-23 expansion region confirmed the species' identity. Phylogenetic trees and parsimony network analysis placed the Maryland isolate in a large grouping of B. longicaudatus populations including those from Alabama, Delaware, Florida, Indiana, Mississippi, South Carolina, and Texas. To our knowledge, this is the first report of B. longicaudatus in Maryland.