Successfully detecting early-stage diseases, before any symptoms are visible to the naked eye, is challenging for both growers and agronomists: understanding the exact strain and potential resistance to pesticide makes this process even more difficult.

However, advancements in agri-tech mean scientific tools are available to support traditional agronomy methods, bringing the laboratory to the farm and unlocking the potential for a greater understanding of crop diseases.

Molecular biology in the field

Can molecular biology take place in a muddy field? The answer is, yes it can! This is because, as with many technologies, molecular diagnostics tools have become much cheaper, smaller, and user-friendly over time. This means you really don’t need to be an expert to use them.

Consequently, many medical technologies such as lateral flow tests – once unknown to those outside the scientific community but now commonly used as at-home COVID tests – or LAMP assays are becoming more common in agriculture. These portable tools can be used to detect and identify crop pests or diseases quickly, and can also indicate whether or not they carry resistance genes that may affect their management.

Rapid, portable scientific testing

In agriculture, lateral flow tests work by detecting the unique proteins within pests and diseases, helping to identify different strains. LAMP machines conduct a similar task, but instead amplify an organism’s DNA to detect its unique DNA sequences.

Both techniques are rapid and highly portable, meaning they can be done almost anywhere. CHAP partner Newcastle University has used our mobile crop science labs to demonstrate blackgrass resistance testing at grower events, but agronomists could just as easily do this in a car or on the tailgate of their pickup.

Suddenly, this makes molecular diagnostics so much more accessible and functional for an agronomist, researcher or even farmer.

Why use molecular biology?

Essentially, molecular biology is the study of the structure and function of biological molecules and how they interact with one another in living organisms, to perform the functions of life.

This molecular information can be very powerful and useful because biological molecules vary between different pests and diseases: there are even slight differences between individuals.

Molecular diagnostics works to identify these different molecules, mainly DNA and proteins, even from very small samples. Understanding what pests or diseases are present in crops or on a farm – even before they have started to cause damage – has the potential to transform crop protection and reduce yield losses.

Early and accurate detection of pathogens or pests would allow growers to make more-informed crop management choices, facilitate the early deployment of biopesticides or biological control agents and allow more targeted use of pesticides.

Worldwide applications

CHAP’s Molecular Diagnostics Laboratory supported work on the Innovate UK-funded Potato Cyst Nematode (PCN) in Kenya project, to develop an assessment tool to enable farmers to identify PCN infestations in their fields.

Potatoes are an important crop for Kenya, but like the UK, farmers face the hidden challenge of PCN, which can cause up to 80% yield loss.

The project involved PES Technologies and the International Centre of Insect Physiology and Ecology (icipe) in Nairobi, who have been working to identify different PCN species by looking at the shape, size and structure of cysts and individual nematodes. CHAP then used molecular diagnostics to confirm identification of these different species, which has been vital in the development of the PCN assessment tool.

The PCN Assessment Tool will enable researchers and farmers to identify PCN-infected areas, to better inform crop-rotation choices.

Valuable agricultural research tool

Taking science to the field can work to support trials and industry research too. This is demonstrated through CHAP’s collaboration with Newcastle University and member, crop protection manufacturer UPL, to conduct in-field latent Septoria (Zymoseptoria tritici) testing in wheat.

As the latent period for Septoria is three to four weeks, understanding the relative levels of disease present can not only give an indication of potential risk, but also show the performance of fungicide treatments previously applied. Newcastle University extracted and tested DNA from leaf samples at trial sites to detect Septoria, using molecular diagnostic techniques. Being able to showcase this at the trial site itself made for an enhanced customer experience, when UPL hosted their trial open days.

Improved accessibility

There will always be a place for laboratory-based molecular diagnostics, but it is exciting to see technology enabling such techniques to make their way into the field. Improving the accessibility of science, sparking ideas, and fostering our understanding of plant health systems.

To find out about our facilities relevant to this article, go to Molecular Diagnostics Laboratory and National Reference Collection. You can also read more about the PCN project in Kenya.

To find out about becoming a member go to our members page. If you have a project idea or want to find out how you can work with CHAP, please send us an email using the enquiries form at the bottom of our homepage.

Please note, the opinions expressed in this article are the author’s own and do not necessarily reflect the views or opinions of CHAP.