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Climate change 'spreads crop pests'

Summary

2 September 2013

Global warming is helping pests and diseases that attack crops to spread around the world, according to a new study published in the journal Nature Climate Change. Researchers from the universities of Exeter and Oxford found crop pests are moving towards the poles as regions warm.

Reporter:

Rebecca Morelle

Report

The researchers looked at more than 600 crop pests from around the world.

These included fungi, such as wheat rust, which is devastating harvests in Africa and the Middle East; insects like the mountain pine beetle that's destroying trees in the US; as well as bacteria, viruses and microscopic nematode worms.

They found that over the past 50 years, these destructive species have been on the move. On average, they're spreading 3km every year, shifting north and south towards the poles.

The scientists say this correlates with warming temperatures, allowing the pests to take hold in areas that were once too cold for them to live in.

Currently, between 10% and 20% of the world's crops are lost to pests - and the team warns that rising global temperatures could make the problem worse. The researchers say that improved surveillance of the problem is needed.