New project to use earth observation data and climate forecasts for targeted management of wheat blast disease

CABI is leading a new project using earth observation data and climate forecasts for targeted management of wheat blast disease in India, Bangladesh, Thailand, Australia, and the United Kingdom.

Wheat blast (Magnaporthe oryzae Triticum or ‘MoT’) is a severe problem in Bangladesh and South America amid humid, warmer climates and is a plant disease of global concern, threatening crop production, biosecurity, and food security.

CABI and partners, with expertise in earth observation, remote sensing, pest and disease modelling, datasets, and information dissemination, are producing wheat blast risk maps to help as part of a targeted management approach to the disease.

Wheat blast is a plant disease of global concern, threatening crop production, biosecurity, and food security (Credit: CABI).

Highly destructive disease

The project is funded by the Science and Technology Facilities Council (STFC) and involves working with Assimila Ltd, Cervantes Agritech, the University of Leicester, RAL Space, CSIRO, and the New South Wales Department of Primary Industries, who are all leading experts in their fields.

First discovered in Brazil in 1985, wheat blast is a highly destructive disease resulting in yield losses of over 50% when environmental conditions are favourable. It gradually spread to Bolivia, Paraguay, and Argentina. In 2016, it emerged in Bangladesh, and in 2018, it was observed in Zambia.

Wheat blast is caused by Magnaporthe oryzae Triticum (MoT), a fungal pathogen that spreads quickly and travels long distances in the air through infected seeds and spores. It is feared the consequences of climate change pose the risk of the disease infecting other wheat-growing areas around the world.

Wheat blast CLIMEX model

So far, CABI and Cervantes Agritech have  developed a wheat blast CLIMEX model – a niche model that is used to indicate where and when pest and diseases may occur given certain weather conditions such as temperature and precipitation.

The model will help to investigate the potential distribution of the disease using eco-physiological tolerances, and global occurrence records. It will also contribute to understanding the phenology of the disease in different locations.

Initial results show a good fit between the modelled suitable areas and the known distribution of wheat blast disease, including potential suitable areas in other countries including Central and North America, Africa, and Australia.

Pascale Bodevin, CABI’s Project Manager for the project, said, ″Climate change has altered the way pests and diseases establish and spread around the world.

″Countries and habitats that would historically be deemed inhabitable by a species, are changing due to rising temperatures and changing precipitation patterns which are expanding the distribution of species into new areas.

″Likewise, the consequences of increased global trade and pathways have led to pests and diseases travelling between countries accidentally, widening the species’ reach.

″Under these conditions, wheat blast is expected to spread mainly in tropical regions. A more humid and warmer climate in the future will likely increase the number of suitable areas for wheat blast in the Southern hemisphere.″

Tools developed

The scientists, by integrating the novel use of earth observation data and modelling methods, are creating a framework which will not only enable the targeted management of wheat blast but also see tools developed to help understand and manage biosecurity risk for countries that are currently free of the disease.

The project’s key research objectives include using earth observation data to classify crop types in temporally and spatially complex environments in Bangladesh; linking niche and infection models with crop-type models to derive actionable risk products.

It also seeks to identify unique spectral signatures of wheat blast using high-resolution remote sensing data and engaging with key stakeholders to understand wheat blast management and how information is currently delivered.

Ms Bodevin added, ″Capturing local data and validating it will enable the project to collaborate with an existing research programme in wheat blast management and extension and outreach programmes in Bangladesh.

″The project is also working with key stakeholders in India and Thailand to understand how information is currently communicated in these countries and evaluate the potential risk of the disease.″

Biological stresses of wheat blast

Future work will focus on improving the distribution and phenology models with more refined stress parameters – conditions that affect the cycle of the disease pathogen such as cold-wet, hot-dry or moist-freezing.

Meanwhile, Cervantes Agritech, is developing a real-time infection model that will identify locations and times when MoT infections can occur. This model will be implemented in the DYMEX modelling platform [a model that helps to forecast pest populations (spatial and temporal) and disease infection] to model MoT dynamics in Bangladesh.

Earth observation data is also being used to detect the biological stresses of wheat blast on wheat in Bangladesh, while scaling drone-mounted hyperspectral reflectance of Wheat Blast is being explored.

Professor Darren Kriticos, Co-founder and Managing Director at Cervantes Agritech of Cervantes Agritech highlighted the importance of this work.

He said, ″The systems that we are developing harness the strengths of EO data and process-based modelling and will help manage MoT in both the short- and long-term. In the short-term, high-risk areas can be targeted for surveillance and management.

″In the long-term, the high-risk areas can be targeted for deployment of resistant wheat varieties or in extreme cases planting other crops. The models we are developing here in Bangladesh can be rapidly and easily deployed to other areas where MoT is a problem, and we will extend the system to other diseases.″

Ms Bodevin added that while CABI is also leading on impact pathways and stakeholder consultation for the project, we are collaborating with key stakeholders in Bangladesh, Australia, India, and Thailand to understand the current knowledge-sharing pathways for wheat blast information within these countries.