An international tillage research group is predicting that global wheat yields will drop by 6% for each degree centigrade of global warming together with increased variability of yield across regions and seasons.

This is the key finding from an international group of agronomists, who used a combination of computer modelling technologies and artificial heating experiments to focus on the responses of wheat to high temperatures. The group included a number of Rothamsted Research scientists.

Some 30 wheat crop models were compared with two previously unpublished data sets from tillage field experiments in which wheat was exposed to mean temperatures ranging from 15 oC to 32oC during the growing season.

The study’s results indicated global wheat production losses of 6% for each degree centigrade of global warming with increased variability of yield across regions and seasons.

“Options exist to adapt and mitigate the adverse effects of climate change on global wheat production,” commented Dr Mikhail Semenov, whose team at Rothamsted Research contributed to the research.

“Breeding for late maturing cultivars with longer grain filling to recapture the temperature-induced loss of biomass and grain yield could be beneficial as long as exposure to heat stress and terminal drought does not become counter-productive.

Optimising this trade-off should be region specific, and crop modelling is a key exploration tool to underpin crop adaptation for a changing climate.”

Professor Martin Parry, leading the 20:20 Wheat Institute Strategic Programme at Rothamsted Research, said that the modelling technology work is an excellent example of collaborative research which will help ensure that agronomists will have the knowledge needed to develop  the crops for the future environments.