Plants in Peril: Part 2
- Rebecca Murray-Watson
- Nov 21, 2019
- 2 min read
Updated: Dec 12, 2019
In response to a comment on last week’s blog, this week I’m looking at how climate change will affect wheat diseases in a little more detail. Wheat is one of the most important food sources worldwide, contributing to nearly 20% of total available calories. It's grown on more land than any other commercial crop, with global production approaches 700 million tonnes per year.
As wheat is both a vital food source and underpins many local economies, understanding how its production is affected by climate change is of utmost importance. In this post, I’d like to highlight a review published a few years ago that looks at how climate change could affect several wheat diseases in different geographic areas.
Below I’ve included an extract from a table detailing the review's outcomes on leaf rust, which can reduce yield by 20%.
Adapted from Juroszek and von Tiedemann (2012). Displays the projected effect of climate change on Puccinia recondita, the pathogen behind leaf rust.
The future outlook for wheat production very much depends on the area of study. Similar to the Brazilian bananas in last week's blog, in some areas, climate change could actually lower disease incidence. However, in other cases, such as in Germany, the situation could get worse. In the UK, the picture remains unclear.
It makes sense that climate change could cause a decrease in disease incidence; just as new areas may open up to pathogens, their current ranges could become inhospitable. It should be noted that although disease incidence may decrease in some regions, that doesn’t mean climate change is ‘good’ for crops; plenty of other studies show increased temperatures or changing rainfall patterns would negatively impact wheat production.
These differing outcomes highlight the need for region-specific action plans and mitigation techniques. While the direct consequences must be dealt with locally, action must be taken at a much higher level to ensure that our food networks can cope with a changing climate.
clontarfmurrays-I agree, the uneven distribution of wealth causes a whole host of global problems, and with climate change it's particularly bitter considering the countries feeling the worst effects are often the least to blame. I'll be watching the proceedings UN Environment Conference in Madrid to see if richer nations become incrementally more willing to accept responsibility for helping the countries who need it.
rm844-Thanks for your encouragement! Nice to hear from someone who actually studies plant diseases. Interesting point about areas where plants could be grown, but aren't; I suppose that brings issues of land-use change if we were to start plating there, but I wonder if moving where we grow plants entirely could help mitigate the effects of terrible diseases (provided the diseases don't move with them...)
Louisa-I’ve heard of a few early warning systems for plants (my sister researches plant diseases!), but upon searching online, I found precious little information on them. However, I did find this rather interesting grant awarded by the Bill and Melinda Gates Foundation for the creation and support of such a system (https://gcgh.grandchallenges.org/grant/disease-and-pest-data-collection-and-early-warning-system).
Several experts have also called for the development of a (European) warning system, so watch this space: https://www.nature.com/news/deadly-new-wheat-disease-threatens-europe-s-crops-1.21424?fbclid=IwAR1ne3UDDOCtie3eGq-cBDp9WQYVnn4-GGzyrrwoAB-eFdSTXKEcawBN7KU
As for GM; GM has huge potential but as with new technologies, it should be done in consultation with those that know the land, which usually means collaboration with local experts. Changing species entirely in Ethiopia, as you mentioned, does not sound like a wise decision… However, changing varieties of…
Planning for the management of future crop epidemics is so important for food security under climate change, but I'm not sure I've ever heard of an early warning system for crop diseases, let alone a global early warning system - is that something you've come across?
There's definitely a major role for genetically modified crops that are higher yield, more resistant to disease, and tolerant of flood and drought (especially in Africa where there has only been limited cultivation of GM so far). However inevitably there are risks associated with wholesale adoption of new varieties: I remember hearing of a case in Ethiopia where a (government-sponsored) switch to maize from a variety of local crops such as tuff and sorghum…
I work on plant diseases and can confirm that one of the greatest threats to food security is climate change. Whilst it's true and some areas can become more suitable to certain crops, there's a host of cultural and infrastructure barriers that may mean that though the areas are environmentally suitable, the new crops will remain ungrown. Regardless, with the last two blogs you've done an excellent job of hightlighting the overlooked threat of agriculture on our food supply systems.