Distribution of Phasmarhabditis (Nematode: Rhabditidae) and Their Gastropod Hosts in California Plant Nurseries and Garden Centers

Jacob Schurkman; Irma Tandingan De Ley; Kyle Anesko; Timothy Paine; Rory Mc Donnell; Adler R Dillman

doi:10.3389/fpls.2022.856863

Distribution of Phasmarhabditis (Nematode: Rhabditidae) and Their Gastropod Hosts in California Plant Nurseries and Garden Centers

Front Plant Sci. 2022 May 17:13:856863. doi: 10.3389/fpls.2022.856863. eCollection 2022.

Authors

Jacob Schurkman¹, Irma Tandingan De Ley¹, Kyle Anesko¹, Timothy Paine², Rory Mc Donnell³, Adler R Dillman¹

Affiliations

¹ Department of Nematology, University of California, Riverside, Riverside, CA, United States.
² Department of Entomology, University of California, Riverside, Riverside, CA, United States.
³ Department of Crop and Soil Science, Oregon State University, Corvallis, OR, United States.

Abstract

Three species of Phasmarhabditis were recovered from 75 nurseries and garden centers in 28 counties in California during fall and winter 2012-2021. A total of 18 mollusk species were recovered, most of them invasive. Nematodes were identified by sequencing the D2-D3 expansion segments of the large subunit (LSU or 28S) rRNA. Based on these surveys, P. californica was the most widespread species (37 isolates, 53.6% recovery); followed by P. hermaphrodita (26 isolates; 37.7% recovery); P. papillosa and a closely related P. papillosa isolate (6 isolates; 8.7% recovery). Nematode isolates were mainly collected from four invasive slugs (Deroceras reticulatum, D. laeve, Arion hortensis agg, Ambigolimax valentianus) and snails (Oxychilus spp. and Discus spp.). Results suggest that P. californica and P. hermaphrodita share an ecological niche in Northern, Central, Coastal, and Southern California, north of Los Angeles County.

Keywords: P. hermaphrodita; P. papillosa; Phasmarhabditis californica; invasive gastropods; nurseries.