# Low-Cost Heating Modalities Allow the Detection of Biomarkers for Plant Infection Using Rapid Evaporative Ionization Mass Spectrometry (REIMS) That Are Pathogen Specific

## TL;DR

This paper shows that low-cost heating tools can be used with a mass spectrometry technique to detect specific plant infection biomarkers, offering a fast and accurate diagnostic method for agriculture.

## Contribution

The novel use of low-cost heating modalities with REIMS to detect pathogen-specific biomarkers in plant infections.

## Key findings

- A 450 nm laser provided the highest diagnostic classification accuracy for plant infection detection.
- REIMS can distinguish between different infection causes using pathogen-specific biomarkers.
- Low-cost heating tools enable in situ and high-throughput plant metabolome analysis.

## Abstract

Agricultural pathogens
reduce annual crop yields by up to 40% and
present a barrier to improving crop production to a level by which
it will be able to support a global population of 9 billion by 2050.
Current diagnostic methods are slow and lack specificity and typically
rely on visual signs of infection, which appear late in the infection
cycle. In this work, we explored whether the ambient ionization method
rapid evaporative ionization mass spectrometry (REIMS) could be used
to detect pathogen-specific biomarkers of infection against two important
pathogens: the nematode and bacteria in the tomato plant (). Unlike previous implementations of REIMS for human clinical diagnostics,
we explored the use of low-cost heating modalities in the form of
a 450 nm laser and soldering iron (both below $200). After optimization,
we found that the 450 nm laser provided the highest level of diagnostic
classification accuracy and, importantly, could distinguish between
infection causes with pathogen-specific biomarkers. This shows both
the novel utility of REIMS for analysis of plant material, which would
allow in situ and high-throughput analysis by the
community for a broad range of plant metabolome applications, and
also the potential of low-cost 450 nm lasers for use beyond this.