Crop Disease Prediction – Forecasting for Common Plant Risks

Food security is one of the biggest problems facing the world today. 

With a growing population, reducing land availability, climate change and political uncertainly affecting farm businesses, the issue is rarely far from the headlines. 
One way to mitigate this, however, is to ensure farm businesses are as efficient and productive as possible.
 
By ensuring crop yields are optimised through a dedicated crop disease management plan, not only is the farm businesses less vulnerable to financial losses, food availability is also optimised for consumers.

In this article, we take a deep dive into crop disease forecasting to help growers generate high-yielding crops and healthy returns. 

What is Plant Disease Forecasting?

Before we start, it’s useful to define what plant disease forecasting is. 

As the name suggests, it involves understanding and evaluating the risks faced by crops and assessing the likelihood of those risks turning into disease.
 
There are a number of ways of forecasting plant diseases which range from the traditional – a field walk and using the naked eye to assess disease potential – to advanced technological solutions such as AI, which are becoming increasingly popular due to their accuracy and ability to pick up factors humans tend to miss. 

Why Make Predictions?

Although this might seem like an obvious question, the fact is many growers don’t make predictions around potential disease incidents. Instead, they either react to disease as it appears, or they blanket apply crop protection products to prevent them developing in the first place. 

But neither of these are the most effective or efficient approach. Waiting for disease to appear before taking action will inevitably lead to some degree of yield loss, and blanket applications are costly, can enhance resistance, and are potentially damaging to the environment. 

The main point of making predictions about crop and plant disease is to prevent diseases occurring. The process takes into consideration different variables such as plant variety, weather conditions present and future, historic disease trends and a host of other factors to assess the risk of disease, enabling the grower, along this their agronomist, to prepare for the most likely outcomes. 

By doing this, farmers can not only take preventative measures against diseases, they can react more quickly to outbreaks, minimising damage and loss of yield. 

Done well, plant disease forecasting leads to less incidents of disease, optimised yields, optimised crop health, and better financial returns. 

How to Forecast using Tools and Calculators

Historically, farm records, plant variety, field conditions, and weather predictions were the tools available to farmers and agronomists to predict the risk of crop diseases. 

But as technology has evolved over recent years, it now plays a significant role in doing this.
 
Technology has the power to combine and analyse far more variables and data than people and, as a result, makes far more accurate predictions.
 
This, in turn, makes a farming business far more efficient and has the potential to increase returns for growers.
 
The tools and calculators used for predicting the incidence of crop disease – including our own RHIZA Contour platform – work by employing data gathering technology to gain insights into the crop, field conditions, plant variety, pest prevalence, and a range of other factors. 

This is done via satellite imagery, drones, hyper-local weather forecasting, and physical fieldwork to assess soil conditions and other parameters. 

Powerful forecasting models then combine all this data to make predictions about the likelihood of specific pests or pathogens occurring in the crop. This information is conveyed back to the farmer and their agronomist via computer software or a mobile app, often along with advice on how to manage the risk. 

Effective tools and calculators continue to provide real-time updates as the crop develops, updating management and input advice in line with the changing conditions. 

There are many benefits of taking a digital, data-led approach to disease forecasting. These include better decision-making, enabling farmers to move from calendar-based applications to apply crop protection products in line with the crop’s requirement. 

It also allows for input levels to be optimised, leading to better financial and environmental outcomes, proactive pest control, minimising the risk of a major outbreak, and enhanced crop yields due to taking a data-first approach. 

Common Crops/Diseases for Forecasting

Although there is theoretically no limit to the number of diseases digital tools can predict, they are typically used to make forecasts about the most damaging diseases, as this is where the biggest efficiencies can be realised. 

Some of the most common diseases they used to predict include:

Septoria tritici

This is the most common disease found in winter wheat. Symptoms include oval lesions, water-soaked patches, leaf yellowing, necrotic brown tissue or death.
  
In severe cases, Septoria tritici can cause up to 50% yield loss and affect grain quality, so forecasting an outbreak is incredibly valuable to farmers.

Fusarium Mycotoxins

Fusarium mycotoxins can reduce cereal crop yields by up to 30% in severe cases, meaning accurate forecasting of the condition is vital.
 
The risk of it occurring are increased by warm, dry springs which lead to spore production, combined with rainfall splashing spores onto the ears (tips) of the plant. High rainfall combined with humidity also encourages spread.

BYDV (Barley Yellow Dwarf Virus)

Despite its names, BYDV occurs in wheat and oats as well as barley, and in the worse cases can cause huge yield reductions of up to 60% in winter wheat and 50% in barley. 

As a result, accurately predicting BYDV and managing the crop to prevent its occurrence is highly desirable to growers. 

Yellow Rust

Yellow Rust mainly affects wheat crops and can lead to yield losses of up to 50%, making it an important disease to forecast. 

Symptoms are yellowish, orange-coloured pustules on leaves of adult plants. They are scattered randomly on younger leaves, which also become pale, yellow or brown.

Clubroot

This affects some of the UK’s staple dinner table vegetables including sprouts, cabbage, cauliflower, turnip, swede and radishes.

Infection comes by way of the microorganism, plasmodiophora brassicae, and can lead to yield drops of up to 10%. However, the pathogen can live in the soil for up to 15 years, causing significant financial damage, making forecasting and managing Clubroot a vital strategy. 

Light Leaf Spot

Light Leaf spot is the most economically damaging disease in the UK for oilseed rape. It used to be traditionally associated with Scotland and Northern England but is now more widespread throughout the UK.
Accurately forecasting Light Leaf Spot can therefore help safeguard farm incomes. 

Ramularia Leaf Spot

Ramularia Leaf Spot is a lesser-known variety of Leaf Spot which can cause yield losses of up to one ton per hectare. It used to be confined to northern regions in spring but is becoming more widespread in winter. Ramularia Leaf Spot is usually associated with barley but there are reports of it affecting wheat and oats so accurately forecast this disease can minimise economic losses. 

The Role of AI and Machine Learning

Although crop disease forecasting technology has been around for a number of years, it is being revolutionised by AI and machine learning. 
Machine learning enables the technology to recognise patterns in the data it collects and refine its own decision making in response to these. 

This means that the more the technology is used on a particular farm, the more accurate its crop disease predictions will become over time. 

As a result, machine learning has the potential to revolutionise farmers’ approach to crop production, disease forecasting, and disease treatment over the coming years, driving significant improvements in yield, crop health, and efficiencies. 

Combining this with the expert eyes of an experienced agronomist or grower will ensure your farming business is elevated to the next level. 

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