Wheat accounts for 20% of the world’s calorie consumption and growers, including those in the UK, have a key role in meeting rising demand.

Alan Tracy, president of US Wheat Associates, estimated that world wheat trade would rise from the current 150m tonnes to more than 200m tonnes by 2030.

See also: Global warming threat to wheat yields 

This offers opportunities for wheat exporters, the top four being USA, EU, Australia and Canada.

But there are many challenges, including yield plateaus in some countries and a shrinking global wheat area as farmers switch to soya bean and maize growing.

Fight for land

“This fight for land is already happening in the US,” said Mr Tracy.

Maize and soya have moved north and west competing with spring wheat, and for maize it is due to corn rootworm resistance.

“In fact, the number-one county for soya production is next to the Canadian border,” he told the Cereal Future Forum in Brussels.

But while the US wheat area has fallen, total production has been maintained, of which half is exported. This is due to an increase in wheat yield.

It’s not just in the US, the same trend is being seen in Eastern Europe and Russia. “The wheat area in Ukraine is trending down. Corn exports are now double those of wheat,” said Mr Tracy.

Yelto Zimmer, researcher at the Thunen Institute of Farm Economics in Germany, said that in Russia, maize and wheat yields were almost the same at 2.5t/ha in 2000. Twelve years later and maize outyields wheat by almost 2t/ha and he believes maize will expand at the expense of wheat.

However, in the short term, he believes there will be no impact of the falling wheat area on prices as livestock farmers switch to maize.

Trade distortions

Another pressure point for wheat exporting countries is subsidised competition, and Mr Tracy pointed to China, India and Turkey as examples where state intervention is distorting the market. “US wheat has been effectively driven out of Egypt by cheap Russian wheat,” he said.

Wheat is also at a disadvantage when it comes to technology, with soya and maize growers benefitting from GM technology. The amount spent on wheat breeding is lagging behind other crops on an area basis.

With yields, Dr Zimmer said the picture is much more positive with an upward trend, except in Europe. Yields here have stagnated, some countries have even seen a decline, such as France and the UK.

Australia

Conserving moisture and employing drastic measures to get on top of glyphosate-resistant weeds have been a key part of grower Chris Reichstein’s (pictured right) wheat strategy in Western Australia.

“The main challenge is weather, and in Western Australia we have seen a decline in rainfall. Since 1900, the average has fallen from 700mm to 600mm, and we are also seeing fewer decent sowing rains.”

To conserve moisture, Mr Reichstein has put a greater emphasis on controlling summer weeds that consume moisture.

He also adds soil amendments and has adopted full stubble retention with a no-till approach. “There is about 95% adoption of no-till in Western Australia.

“Timings also have to be spot on as we can’t afford to lose any moisture,” said Mr Reichstein.

Another challenge has been herbicide resistance and he sees Western Australia as a world leader in this. “We bought the land five years ago and found it came with Round-up ready ryegrass.

“We have finally got on top of this through an integrated weed management approach.”

The first step was herbicide resistance testing. “If you don’t measure it, you can’t manage it,” he said.

Rotation is the second measure, both in terms of a wider range of cropping and herbicide actives applied. “Sometimes you find that old chemistry may work.”

Mr Reichstein then gives fields an “autumn tickle”, disturbing the soil to encourage germination and then knock down weeds – similar to stale seed-beds in the UK to tackle blackgrass.

“We then go in with a ‘double knock’ – first glyphosate and then 14 days later with paraquat to clean out any remaining weeds.”

Upping seed rates also helps. “The normal rate is 70kg/ha, but we have had to go as high as 100kg/ha.”

At harvest, he swaths and sprays with a desiccant to ensure there is no viable weed seed and uses Chaff Carts behind the combine to capture the weed seeds. “The cart spreads straw while weed seed is collected, dumped and burnt.”

Other machines (Chaff Lines) put chaff into tramlines, so weeds face a hostile environment. Other farmers have adopted windrow (straw) burning as this helps take pressure off herbicides, he explained.

Mr Reichstein had also taken drastic measures to improve soil quality. “Our soils are like sand being shallow duplex soils and we have looked to increase the clay content.”

Duplex soils are those with contrasting textures between soil layers. It involves physically digging out the lower clay layer and spreading it to achieve a target of 5% clay content.

France

“Farming is a risky business,” said French wheat grower Philippe Heusele (pictured below), who has adopted a range of measures to make his business more resilient to price volatility.

He farms 406ha of cropping 50km west of Paris, including wheat, spring barley, sugar beet, potatoes, hemp and flax for fibre.

A key part of his strategy is diversifying cropping and adding value where possible. “Sugar beet is sold for biofuel, potatoes to McCain, green beans for canning, flax for fibre and hemp for fibre and seed,” he said.

“We sell through a co-op and use pool prices for cereals. Crops are grown on contract wherever possible, with wheat on a pool price plus premium contract and potatoes at an agreed fixed price.”

He also has crop insurance covering for losses, such as hail storms. The scheme covers for dramatic losses that leave the crop yielding less than 70% of average yield. “In 2009, two-thirds of the rape was damaged by hail. It covers for 13 different possibilities.”

He is also taking advantage of a government income tax smoothing system. “It allows you to pay in the good years and take out in the bad years.”

CAP reform has left French farmers at a disadvantage. “Arable farmers in France are being paid €85/ha less than farmers in Germany,” said Mr Heusele.

Like in the UK, French growers face a wheat yield plateau. “Our main concern is how to break through this ceiling; I can’t seem to get past the 9t/ha barrier.” He puts part of the blame on the stricter use of nitrogen fertiliser.

Most of Mr Heusele’s wheat is for the quality market with a minimum protein requirements. However, protein values are declining on his farm and across France. It has fallen from 12.5% in 2003 to 11.1% in 2014, compared with a UK average of 11.3% in 2014.

Germany

More stringent nitrogen rules could spell the end to milling wheat growing in some parts of Germany.

Doreen Riske (pictured) farms 2,350ha in north-east Germany, 100km from the Polish border, growing winter cereal, potatoes, sugar beet, peas and lupins.

A harsh climate has always been a feature, with cold winters and temperatures as low as -20C. But conditions during the growing season are becoming more extreme, often being very dry and cold in late spring/early summer and with wetter summers.

A key crop is wheat – quality wheat for milling and baking – but new rules could see nitrogen rates cut by 40-50kg/ha.

“We use a N sensor and N-check [in-field leaf tissue analysis] and apply according to the results, typically 188-220kg/ha in three to four dressings,” she said.

The nitrogen balance (surplus) was 54kg/ha of N a year for 2012-2014, which is not quite enough for meeting protein specs and so Ms Riske is looking at other options.

“I don’t know what the new fertiliser regulations will mean and if there is a future for quality wheat. We may have to consider growing C category [feed] wheat instead,” she said.

The wheat yield frontier

New technology and advances in agronomy have a vital role in raising wheat yields, but deploying existing technology could raise the UK average by 25%.

The key question being asked in light of a rising population and limited land availability is where the extra yield is going to come from?

“We are seeing a 1%/year increase in genetic gain for yield, but this is not enough to keep up with rising demand in food,” warned Matthew Reynolds (pictured below) of the International Maize and Wheat Improvement Center (CIMMYT) based in Mexico.

Breeding

However, it’s not all doom and gloom as there are genetic resources yet to be looked at.

“There are half a million accessions [registered gene sequences] worldwide and 170,000 in the World Wheat Collection at CIMMYT.

“Another example of genetic resource is crossing with close wild relatives to produce synthetic wheat. Only 8% of wild species have been used and you don’t need transgenics [GM] to get more diversity,” said Dr Reynolds.

He believes they could be a future source of disease resistance and better drought tolerance.

Driving global breeding efforts is the Global Wheat Initiative, which was established in 2011 following endorsement from the G20 farm ministers. It brings together 15 countries, two international research organisations and nine private companies, including Bayer CropScience, CIMMYT and the UK’s Biotechnology and Biological Sciences Research Council.

The aim is to raise yields by 50% and there are various expert working groups, including one co-ordinating the sequencing of the wheat genome.

Yield potential

To look at what’s possible in terms of wheat production, Joachim Lammel (pictured bottom) of Yara International calculated backwards from the theoretical maximum with current varieties.

In north-west Germany, 23t/ha is theoretically possible if using 100% of solar energy, but in reality the upper maximum is 16t/ha when taking cloud cover in an average year into account.

Yara has been investigating canopy efficiency in capturing light energy, which involved irrigating crops and fertigation [water and nutrients applied].

“We found there is a 4.99t/ha irrigation effect and 0.6t/ha response to fertigation. Therefore, the highest attainable yield is 12.9t/ha, but farm yields are averaging at 7.3t/ha,” he said.

To explore the role of light interception, Yara researchers looked at different plot sizes – large plots, a plot measuring 40x40cm, plus one at 80x80cm with the inner 40x40cm portion harvested.

The big plot yielded 11.7t/ha, 80x80cm gave 14.8t/ha and 40x40cm yielded 19.8t/ha.

“We concluded that light interception is an important factor and, therefore, genetic potential of wheat is much higher than that seen in the field,” said Dr Lammel.

One way to improve interception is with spikes on ears. Dr Reynolds highlighted that spikes on ears of elite spring wheat can intercept up to 45% of sunlight, but are overlooked by breeders.

He has been looking at spike photosynthesis, but it is difficult to measure as plants can recycle carbon and oxygen so researchers can’t use gas exchange as a measure of photosynthesis.

“Instead we shaded spikelets to see what happened. We now have a molecular marker for spike photosynthesis and are just about to publish our findings.”

There are also developments in selection technology with drones identifying drought-tolerant varieties by thermal imaging crop plots.

Canopy temperature is associated with heat stress, the cooler it is, the better the plant can withstand drought, he explained.

Closing the gap

Bayer CropScience’s global cereals manager Steve Patterson (pictured right) described the technology and agronomy challenge as “significant”.

“There is no single solution – it will be about better integrating all technologies with ‘new’ agronomy.”

Using today’s technology and employing best practice, average yields could rise by an estimated 50% in Mexico and North Dakota, while the UK, which already has a high average yield, could see an extra 25% (see graphic on p56).

He said the next step up would require new technology, including weed management systems for grassweeds and broad-leaved weeds and new traits.

“To achieve this, we need to integrate chemistry, biological control and traits,” said Mr Patterson.

Bayer is playing its part having set up a long-term innovation programme to enhance wheat productivity. The company has a 10-year plan to invest in research and development through to 2020.

One example is developing hybrid wheat and Mr Patterson believes varieties offering improved yield will be ready for market after 2020.

The company has also established a Weed Research Centre in Frankfurt, Germany. “One-third of yield can be lost with weeds – more than pathogens and pests globally,” stressed Christine Brunel-Ligneau, head of integrated weed management.

Blackgrass is a key problem in the UK and some other parts of Europe, while other resistant grassweed species are a headache for farmers elsewhere in the world.

She said it was a worsening situation, with wheat at the top of the resistance league table with 70 resistant species, while maize has 61.

Mr Patterson believes collaboration is essential in delivering the new technology.

An example is the VIB Research Institute near Ghent, which works in close partnership with four universities and is funded by the Flemish government.

The research hub also hosts companies, including Bayer and other agchem firms.

Scientists from both organisations are collaborating with the aim of producing crops with higher yields and improved tolerance to stresses such as drought or soil salinity.

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 About 230 experts, farmer breeders and other representatives recently attended the Bayer CropScience Cereal Future Forum in Brussels. The aim was to discuss the challenges and new approaches to enhance wheat yield and quality.