Increasing wheat yield without sacrificing food safety
Over the centuries since wheat was first domesticated, it has become one of the world's most productive and important crops. Rising consumption per capita and the demand for grain for fuel as well as food underscore the need for higher global yields. A recent study published in the Annals of Applied Biology outlines the delicate balance between boosting yields
Inarguably, plant breeding will have to play its part. In recent years, the study of complex traits has been greatly facilitated by the development of tools and resources to identify quantitative trait loci and characterize individual genes contained within them. Biotechnology (which is currently known as genetic modification, though it could soon mean the application of ‘post-GM’ technologies, such as cisgenesis) will also likely play a role, though it depends on market acceptance. Moreover, the industry must also prepare wheat to meet the problems of drought, high temperature and increasing carbon dioxide concentration that are anticipated to come about as a result of climate change.
Owing in part to the damaging effects of bad headlines (such as the recent attacks on acrylamide), wheat producers must also consider food safety concerns. For example, as wheat products are among the highest contributors to dietary acrylamide intake, the authors focus on this contaminant (which forms from free asparagine and reducing sugars during high temperature cooking and processing) in relation to breeding.
“Breeders must beware of inadvertently increasing acrylamide-forming potential while selecting for yield or other traits, because there is evidence from several crop species of links between asparagine metabolism, yield and protein content,” the authors wrote.
Wheat breeding has already been extremely successful in increasing yield in some regions; thus addressing the problems in areas where yield is still much lower should be a priority. However, if yield were increased elsewhere, farmers in developed countries with high operating costs would need to see improvement to remain competitive. Moreover, high yield in productive regions has come not only from genotypic improvement but also from mechanization and heavy use of agrochemicals—which may not be environmentally sustainable, the authors point out.
Source: The Annals of Applied Biology
DOI: 10.1111/aab.12108
“Food security: the challenge of increasing wheat yield and the importance of not compromising food safety”
Authors: T. Curtis, N. G. Halford
Agricultural technologies could boost global crop yields as much as 67%
Amid increased pressure to feed a growing global population, a new report by the International Food Policy Research Institute (IFPRI) measures the impacts of agricultural innovation on farm productivity, prices, hunger, and trade flows as we approach 2050 and identifies practices that could help farmers worldwide improve the sustainability of growing three of the world's main staple crops: maize, rice, and wheat.
Using a first-of-its-kind data model, IFPRI pinpoints 11 agricultural technologies and practices that can most significantly reduce food prices and food insecurity in developing nations: crop protection, drip irrigation, drought tolerance, heat tolerance, integrated soil fertility management, no-till farming, nutrient use efficiency, organic agriculture, precision agriculture, sprinkler irrigation and water harvesting. Among key findings:
- Although no-till farming alone could increase maize yields by 20%, irrigating the same no-till fields could increase maize yields by 67% in 2050,
- nitrogen-use efficiency could increase rice crop yields by 22%, but irrigation increased the yields by another 21%, and
- heat-tolerant varieties of wheat could increase crop yields from a 17% increase to a 23% increase with irrigation.
In addition, if farmers stacked agricultural technologies in order of crop production schedules, the combination of agricultural technologies and practices could reduce food prices by up to 49% for maize, up to 43% for rice and 45% for wheat due to increased crop productivity. Still, the authors pointed out that the detrimental effects of climate change can’t be overstated. It could decrease maize yields by as much as 18% by 2050 – making it even more difficult to feed the world if farmers cannot adopt production-boosting agricultural technologies in their regions.
Based on current projections, stacked technologies could reduce food insecurity by as much as 36%. Making this a reality, however, depends on farmers gaining access to these technologies and learning how to use them. This underscores the need for improved agricultural education to ensure that farmers are able to use the best available technologies for their region and resources.
Source: The International Food Policy Research Institute
“Food security in a world of natural resource scarcity”
Authors: Mark W. Rosegrant, Jawo Koo, Nicola Cenacchi, Claudia Ringler, Richard Robertson, Myles Fisher, Cindy Cox, Karen Garrett, Nicostrato D. Perez, Pascale Sabbagh
Ancient einkorn wheat shows promising nutrition
The hulled wheat einkorn (Triticum monococcum L. ssp. monococcum), a close relative of durum and bread wheat that was a staple food of early farmers, is returning to the spotlight as a low-impact crop with a promising nutritional profile. Cropped only in small areas of the Mediterranean region and continental Europe, this ancient wheat has some notable dietary advantages over polyploid wheats, though it’s poor in dietary fiber.
Einkorn wholemeal is rich in proteins, lipids (mostly unsaturated fatty acids), fructans and trace elements, including zinc and iron. Moreover, the good concentration of several antioxidant compounds (carotenoids, tocols, conjugated polyphenols, alkylresorcinols and phytosterols) and low β-amylase and lipoxygenase activities—which limit antioxidant degradation during food processing—contribute to the excellent nutritional properties of its flour, superior to those of other wheats.
Conversely, einkorn has relatively low bound polyphenol content and high polyphenol oxidase activity. In spite of eliciting weaker toxic reactions than other Triticum species, einkorn is not suitable for celiacs. Current trends towards the consumption of functional foods suggest that this cereal may still play a significant role in human consumption, especially in the development of new or special foods with superior nutritional quality.
Source: The Journal of the Science of Food and Agriculture
DOI: 10.1002 /jsfa.6382
Authors: Alyssa Hidalgo and Andrea Brandolini
Closing the climate change knowledge gap
Recent changes in crop yields, which are likely to be affected by climate change, will no doubt have an impact future global food security. The authors of a recent study developed a spatially explicit global dataset of historical yields for four major cereal and legume crops—maize, soybean, rice and wheat—to explore changes in mean, year-to-year variation and annual rate of change in crop yields for the 1982-2006 period.
The authors concede that although their understanding of the effects of recent climate change (particularly the increased incidence of climate extremes) on crop yields remains limited, the dataset offers opportunities to close parts of this knowledge gap. They called its development a marked advance in the compilation of global agricultural datasets, which will help improve monitoring and short-term prediction of the status of food availability at a global scale. (Past research has relied on FAO data to analyze trends and temporal variation in yields, though they data cannot be applied to depict the spatial variation of yield within a country.)
Analyses of the dataset showed that crop yields became higher and more stable at the global level, and the global yields of the three cereal crops (maize, rice and wheat) never stagnated between 1994 and 2006.
However, at the latitudinal-mean level, the results corroborate the yield stagnation and collapses in some regions that were previously reported and revealed that regions in the low and mid latitudes of the Southern Hemisphere, where many developing countries are located, faced increased year-to-year yield variation in the recent period.The increases in year-to-year yield variation were at least partly responsible for the yield stagnation and collapses. Further research is needed to elucidate the mechanisms underlying the linkages between the increased year-to-year yield variation and yield stagnation or collapse.
Source: Global Ecology and Biogeography
DOI: 10.1111/geb.12120
“Historical changes in global yields: major cereal and legume crops from 1982 to 2006”
Authors: Toshichika Iizumi, Masayuki Yokozawa, Gen Sakurai, Maria Isabel Travasso, Vladimir Romanenkov, Pascal Oettli, Terry Newby, Yasushi Ishigooka, Jun Furuya