# The NEMA Device for Efficient Extraction and Rearing of Entomopathogenic Nematodes

## TL;DR

A new device called the NEMA Device simplifies the collection and breeding of beneficial nematodes, making them more accessible for research and sustainable agriculture.

## Contribution

The NEMA Device is a novel, portable, and efficient tool that combines nematode extraction and rearing into one system.

## Key findings

- The NEMA Device recovered more nematodes from soil than traditional methods like the Baermann funnel.
- It produced comparable nematode numbers to the White trap method while being easier to use and less prone to contamination.
- The device is scalable, cost-effective, and suitable for both lab and field use.

## Abstract

Nematodes are tiny worms found in soil that play important roles in farming and the environment. Some types, called entomopathogenic nematodes (EPNs), help naturally control insect pests, reducing the need for chemical pesticides. To study or use these helpful nematodes, scientists need to collect them from soil and raise more in laboratories. Traditional tools for conducting this are often slow, messy, and hard to use outside of a lab. In this study, we designed a new tool called the NEMA Device, made from common plumbing parts, that combines both collecting and raising nematodes into one simple system. We tested the NEMA Device with two different nematode species and found that it recovered more nematodes from soil than standard methods and produced just as many new ones. The device was also easier to use, more portable, and less likely to become contaminated. By making it easier and more reliable to work with beneficial nematodes, the NEMA Device could help more farmers, students, and scientists use these natural pest controllers in both research and agriculture. This could support more sustainable, low-chemical approaches to growing food while making nematode research more accessible around the world.

Entomopathogenic nematodes (EPNs) are valuable biological control agents and research models in agriculture and ecology. Traditional extraction and rearing methods for EPNs, such as the Baermann funnel and White trap, work well but have limitations in efficiency and practicality. The NEMA Device, constructed from PVC components, was designed to address these limitations by combining extraction and rearing into a single tool with improved portability, scalability, and ease of use. The efficiency of the NEMA Device was evaluated by comparing it to the conventional Baermann funnel extraction method and the White trap method for nematode multiplication. Validation of the instrument was performed using two nematode species, Steinernema khuongi and Heterorhabditis bacteriophora, which vary in size and can be used for pest control. Our results demonstrated that the NEMA Device achieved higher recovery rates of both S. khuongi and H. bacteriophora compared to the Baermann method. Additionally, the production rate of nematodes using the NEMA Device was comparable to that of the White trap method, with no significant difference observed between the two methods. The NEMA Device offers a standardized, cost-effective methodology for the extraction and multiplication of EPNs, enhancing the accessibility and efficiency of studying these agriculturally important nematodes and potentially improving biological control outcomes.