Public Release: 26-Dec-2018
European wheat lacks climate resilience
European farmers need to take a new course with regard to ensuring climate-resilience of important crops such as wheat
Aarhus University
The climate is not only warming, it is also becoming more variable and extreme. Such unpredictable weather can weaken global food security if major crops such as wheat are not sufficiently resilient – and if we are not properly prepared.
A group of European researchers, including Professor Jørgen E. Olesen from the Department of Agroecology at Aarhus University, has found that current breeding programmes and cultivar selection practices do not provide the needed resilience to climate change.
– The current breeding programmes and cultivar selection practices do not sufficiently prepare for climatic uncertainty and variability, the authors state in a paper recently published in PNAS (Proceedings of the National Academy of Sciences). Not only that – the response diversity of wheat on farmers’ fields in most European countries has worsened in the past five to fifteen years, depending on country.
Researchers predict that greater variability and extremeness of local weather conditions will lead to reduced yields in wheat and increased yield variability.
– Needless to say, decreased yields are not conducive to food security, but higher yield variability also poses problems. It can lead to a market with greater speculation and price volatility. This may threaten stable access to food by the poor, which in turn can enhance political instability and migration, Jørgen E. Olesen points out.
Decreasing variation in response diversity
The researchers base their assessments on thousands of yield observations of wheat cultivars in nine European countries for qualifying how different cultivars respond to weather. The researchers identified the variation of wheat response diversity on farmers’ fields and demonstrated the relation to climate resilience.
The yield responses of all cultivars to different weather events were relatively similar within northern and central Europe, and within southern European countries – the latter particularly with regard to durum wheat. There were serious gaps in wheat resilience across all Europe, especially with regard to yield performance under abundant rain.
– The lack of response diversity can pose serious problems with regard to food security. Therefore, farmers, breeders, and dealers in seeds and grain need to pay more attention to the diversity of cultivars grown, warns Professor Jørgen E. Olesen.
Climate resilience is imperative
Wheat is an important staple food crop in Europe and is the leading source of plant protein in our diet globally, so it is important to ensure that we have climate-resilient wheat cultivars on hand.
Rain, drought, heat or cold at vulnerable times during the growing season can seriously damage yields. Wheat yield is generally sensitive to even a few days of exposure to waterlogging and to wet weather that favours disease. In addition, heat stress rather than drought sensitivity appears to be a limiting factor for adaptation of wheat to climate change in Europe.
The dominant approach of adapting crops to climate change by tailoring genotypes to the most likely long-term change is likely insufficient. The capacity of a single crop variety to maintain good yield performance under climatic variability and extremes is limited, but diversity in responses to critical weather events can effectively enhance climate resilience. Therefore, a set of cultivars with diverse responses to critical weather conditions is prerequisite to promoting crop climate resilience.
The authors stress that the need for climate resilience of staple food crops such as wheat must be better articulated. Increased awareness could foster governance of resilience through research and breeding programmes, incentives and regulation.
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You can read the article “Decline in climate resilience of European wheat” published in PNAS here.
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Rent Seeking 101
First Principle
– there is always a looming existential crisis unless more funding for research is provided to provide policy answers.
ex: “…unpredictable weather can weaken global food security if major crops such as wheat are not sufficiently resilient – and if we are not properly prepared.”
Second Principle
– We’re just the group that can provide that research and communicate it to the public and policy makers.
ex: “The authors stress that the need for climate resilience of staple food crops such as wheat must be better articulated. Increased awareness could foster governance of resilience through research and breeding programmes, incentives and regulation.”
Desired outcome: Now, Show me the money!!!
It has become tiresome to read papers that threaten bad outcomes in the near future, while not giving evidence of bad outcomes in the recent past.
When will this global warming threat start to show itself, so we can read a refreshing paper that starts “IN THE RECENT PAST we have found these detriments….”
These authors even have a reference to some recent past work, the start of which is
[HTML] Climate variation explains a third of global crop yield variability
DK Ray, JS Gerber, GK MacDonald, PC West – Nature communications, 2015 – nature.com
Many studies have examined the role of mean climate change in agriculture, but an
understanding of the influence of inter-annual climate variations on crop yields in different
regions remains elusive. We use detailed crop statistics time series for~ 13,500 political
units to examine how recent climate variability led to variations in maize, rice, wheat and
soybean crop yields worldwide. While some areas show no significant influence of climate
variability, in substantial areas of the global breadbaskets,> 60% of the yield variability can …”
See, they write that “understanding of the influence of inter-annual climate variations on crop yields in different regions remains elusive.” Yet the present authors being discussed omit to stress this uncertainty in their quest to produce the panic that loosens the pocket strings of the research funding bodies. It is all so cynical.
Me, when it comes to farming yields and weather, I prefer to listen to farmers with dirt on their hands. Actual dirt, that is, not linguistic dirt. Geoff.
BTW, did you also notice the absence of evidence that the climate is becoming more heavy with variables to be feared, induced by climate change? When I study actual figures about increased forced variability, I find it is indeed a fugitive will o’ the wisp.
‘The climate is not only warming, it is also becoming more variable and extreme.’
A No True Scotsman fallacy.
It is just an assertion. Without proof or even evidence.
Gamecock,
You can do what I have just done for my home town, Melbourne. Maybe the many Victorian wheat growers are close enough to feel some of the same weather.
Can you see a trend to more, warmer, exceptional days? I cannot. That dotted green regression line looks quite level to me. Geoff
http://www.geoffstuff.com/melb_hottest_days.jpg
Turtles all the way down.
Yet more money wasted on useless “research”. The money could have been put to good use elswewhere.
I expect the referenced paper is a load of crap & haven’t bothered to read it. However the headline raises an interesting point; Europe, America and other advanced countries gain their high crop yields (in part) from raising monocultures. Not only does an entire region grow the same crop, it is all a clone from a single prototypical high-yield plant. This lack of genetic variation creates a situation with very low resilience and therefore creates a high risk of widespread crop failure from such things as pests and disease that would only affect a few small areas in other circumstances.
I seem to recollect that the world record for wheat yields was grown by a farmer in New Zealand in 2017 where a season of perfect weather and skilled crop management gave a yield of 16.791 tonnes per hectare, almost 250 bushels per acre!
The main danger to wheat crops in Europe is from frost with no snow cover, and lack of rain in the grain filling period.
In the UK we are usually lucky and have yields of wheat which vary from 8 to 10 tonnes per hectare, whereas in Eastern Europe yields can vary between 6 tonnes per hectare and zero.
In the dry summer of 2018 in the UK wheat yields averaged about 7.5 tonnes per hectare.
Here is a graph of the steady increase of wheat production and decrease in area harvested in Europe from FAOSTAT.
Wheat yields are mainly a function of good agricultural practices and demand pull, not of weather and climate.
http://www.fao.org/faostat/en/#data/QC/visualize
“The climate is not only warming, it is also becoming more variable and extreme.” The data does not support it The climate has not been any more variable and extreme than it has been in the past. The climate change that we have been experiencing is so small that it takes networks of very sophisticated sensors decades to even detect it,
Meanwhile, in the real world, wheat is grown over a very wide range of climate zones. This map is for the USA, but you get the idea:
Note that, for example, hard red winter wheat is grown from Canada to south Texas.
Wheat yields continue to climb, worldwide. One of the reason is that wheat, a C3 grass, responds very, very positively to higher CO2 levels. Thanks to the good folks at http://co2science.org here is a list of some of the papers about studies of CO2’s benefits fortriticum aestivum (wheat):
Akin, D.E., Kimball, B.A., Windham, W.R., Pinter Jr., P.J., Wall, G.W., Garcia, R.L., LaMorte, W.H. and Morrison III, W.H. 1995. Effect of free-air CO2 enrichment (FACE) on forage quality of wheat. Animal Feed Science and Technology 53: 29-43.
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Balaguer, L., Barnes, J.D., Panicucci, A. and Borland, A.M. 1995. Production and utilization of assimilates in wheat (Triticum aestivum L.) leaves exposed to elevated O3 and/or CO2. New Phytologist 129: 557-568.
Barrett, D.J., Richardson, A.E. and Gifford, R.M. 1998. Elevated atmospheric CO2 concentrations increase wheat root phosphate activity when growth is limited by phosphorus. Australian Journal of Plant Physiology 25: 87-93.
Batts, G.R., Morison, J.I.L., Ellis, R.H., Hadley, P. and Wheeler, T.R. 1997. Effects of CO2 and temperature on growth and yield of crops of winter wheat over four seasons. European Journal of Agronomy 7: 43-52.
Bencze, S., Veisz, O. and Bedo, Z. 2005. Effect of elevated CO2 and high temperature on the photosynthesis and yield of wheat. Cereal Research Communications 33: 385-388.
Bencze, S., Veisz, O. and Bedo, Z. 2004a. Effects of high atmospheric CO2 and heat stress on phytomass, yield and grain quality of winter wheat. Cereal Research Communications 32: 75-82.
Bencze, S., Veisz, O. and Bedo, Z. 2004b. Effects of high atmospheric CO2 on the morphological and heading characteristics of winter wheat. Cereal Research Communications 32: 233-240.
Benlloch-Gonzalez, M., Bochicchio, R., Berger, J., Bramley, H. and Palta, J.A. 2014. High temperature reduces the positive effect of elevated CO2 on wheat root system growth. Field Crops Research 165: 71-78.
Bunce, J.A. 2016. Responses of soybeans and wheat to elevated CO2 in free-air and open top chamber systems. Field Crops Research 186: 78-85.
Butterly, C.R., Armstrong, R., Chen, D. and Tang, C. 2015. Carbon and nitrogen partitioning of wheat and field pea grown with two nitrogen levels under elevated CO2. Plant and Soil 391: 367-382.
Cardoso-Vilhena, J., Balaguer, L., Eamus, D., Ollerenshaw, J. and Barnes, J. 2004. Mechanisms underlying the amelioration of O3-induced damage by elevated atmospheric concentrations of CO2. Journal of Experimental Botany 55: 771-781.
Cardoso-Vilhena, J. and Barnes, J. 2001. Does nitrogen supply affect the response of wheat (Triticum aestivum cv. Hanno) to the combination of elevated CO2 and O3? Journal of Experimental Botany 52: 1901-1911.
Chen, F.J., Wu, G. and Ge, F. 2004. Impacts of elevated CO2 on the population abundance and reproductive activity of aphid Sitobion avenae Fabricius feeding on spring wheat. JEN 128: 723-730.
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Christ, R.A. and Korner, C. 1995. Responses of shoot and root gas exchange, leaf blade expansion and biomass production to pulses of elevated CO2 in hydroponic wheat. Journal of Experimental Botany 46: 1661-1667.
Dahal, K., Knowles, V.L., Plaxton, W.C. and Huner, N.P.A. 2014. Enhancement of photosynthetic performance, water use efficiency and grain yield during long-term growth under elevated CO2 in wheat and rye is growth temperature and cultivar dependent. Environmental and Experimental Botany 106: 207-220.
Deepak, S.S. and Agrawal, M. 1999. Growth and yield responses of wheat plants to elevated levels of CO2 and SO2, singly and in combination. Environmental Pollution 104: 411-419.
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Dijkstra, P., Schapendonk, A.H.M.C., Groenwold, K., Jansen, M. and Van de Geijn, S.C. 1999. Seasonal changes in the response of winter wheat to elevated atmospheric CO2 concentration grown in open-top chambers and field tracking enclosures. Global Change Biology 5: 563-576.
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It’s just as well there are clever people about to tell the farmers what’s going on or they’d be trying to grow the same crops year after year not seeing yeilds drop and income falling. Sarc
James Bull
For at least 6,000 years wheat has been grown and is still being grown in southern Iraq-Khuzistan and in Sind. The two hottest non-desert areas in the World with summer temperatures regularily 50+ C.
If there is a place in the World too hot for wheat it hasn’t been found yet.
PS They grow a lot of barley there too, so your beer is climate-proof too.
It’s too bad that large agribusinesses are too dumb to know what to plant and that they have a non-farming academic telling them how to run their multi-national farming enterprises. Or, maybe optimizing the yield for a narrower range is a better bet than selecting a seed that will have a lower crop yield, but will produce over a wider range of possible weather conditions.
I can believe cultivated wheat, worldwide, lacks the diversity to withstand much climate variation at all. This paper failed to prove that.
As a thought experiment alone, consider that a farmer who wants to be successful copies what a successful farmer does, right down to the selection of not just what to plant but the actual variety of anything planted. So we have more and more farmers depending on fewer and fewer varieties until they all plant just one. Just one little disruption as e.g., the fungus currently decimating banana crops, and an entire season or even several is suddenly shot. But the research as described in this report did not support this conclusion.
http://agridata.ec.europa.eu/extensions/DashboardCereals/CerealsProduction.html