Successful Propagation of Single-Pair Nematode Cultures on Pluronic-Enhanced Carrot Discs

Pratylenchus penetrans (Ppen) is an economically important plant-parasitic nematode (PPN), which can be challenging to study in culture. There is great interest in potential control of Ppen through manipulation of its bacterial endosymbionts Wolbachia and ‘ Candidatus Cardinium’. With a broad host range of over 300 plant species, Ppen is a prime candidate for genomics and transcriptomics studies aimed at understanding parasitism and potential biological control approaches. However, these studies require the ability to culture large populations and establish isofemale lines in which host genotype diversity is minimized and maternally inherited endosymbiont status is uniform, particularly because endosymbiont prevalence is typically less than 100% in natural populations. Establishing aseptic isofemale lines has been traditionally challenging for Ppen due to the biology of this sexually reproducing migratory endoparasite. Here, we describe the development of an optimized reproducible protocol for establishing Ppen isofemale lines using surface-sterilized carrot discs and Pluronic F-127 gel, enabling pure, contamination-free cultures under laboratory conditions. Among various tested media, only carrot discs in Pluronic gel supported full development from juveniles to reproductive adults. This new method promises to facilitate numerous studies on both PPN–plant interactions and PPN–endosymbiont interactions and may prove particularly useful for genomic and transcriptomic and symbiont manipulation experiments. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .