Global Plant Council Blog

Plant Science for Global Challenges

Tag: wheat

State of the art research meets breeding for wheat’s future

By Mathew Reynolds, Wheat Physiologist at, CIMMYT

First post of our “Global Collaboration” series

Wheat is the most widely grown crop in the world, currently providing about 20 percent of human calorie consumption.  However, demand is predicted to increase by 60 percent within just 30 years, while long-term climate trends threaten to reduce wheat productivity, especially in less developed countries.  

Ravi Singh presents rust resistance wheat trials to SAGARPA officials. Ciudad Obregon, Mexico 2017. Credit: CIMMYT/Alfonso Cortés

CIMMYT, HeDWIC and IWYP

For over half a century, the International Wheat Improvement Network (IWIN), coordinated by CIMMYT, has been a global leader in breeding and disseminating improved wheat varieties to combat this problem, with a major focus on the constraints of resource poor farmers.

Two complementary networks — the Heat and Drought Wheat Improvement Consortium (HeDWIC) and the International Wheat Yield Partnership (IWYP) — are helping to meet the future demand for wheat consumption through global collaboration and technological partnership.

By harnessing the latest technologies in crop physiology, genetics and breeding, network researchers support the development of new varieties that aim to be more climate resilient, in the case of HeDWIC and with higher yield potential, in the case of IWYP

Novel approaches

These novel approaches to collaboration take wheat research from the theoretical to the practical and incorporate science into real-life breeding scenarios.  Methods such as screening genetic resources for physiological traits related to radiation use efficiency and identifying common genetic bases for heat and drought adaptation are leading to more precise breeding strategies and more data for models of genotype-by-environment interaction that help build new plant types and experimental environments for future climates.

IWYP addresses the challenge of raising the genetic wheat yield potential of wheat by up to 50 percent in the next two decades. Achieving this goal requires a strategic and collaborative approach to enable the best scientific teams from across the globe to work together in an integrated program. TheIWYP model of collaboration fosters linkages between ongoing research platforms to develop a cohesive portfolio of activities that maximizes the probability of impact in farmers’ fields IWYP research uses genomic selection to complement the crossing of complex traits by identifying favorable allele combinations among progeny.  The resulting products are delivered to national wheat programs worldwide through the IWIN international nursery system.

Wheat field trip
Credit: CIMMYT

Recently, IWYP research achieved genetic gains through the strategic crossing of biomass and harvest index — source and sink — an approach that also validates the feasibility of incorporating exotic germplasm into mainstream breeding efforts.

In the case of HeDWIC, intensified — and possibly new — breeding strategies are needed to improve the yield potential of wheat in hotter and drier environments. This also requires a combined effort, using genetic diversity with physiological and molecular breeding and bioinformatic technologies, along with the adoption of improved agronomic practices by farmers. The approach already has proof of concept in the release and adoption of three heat and drought tolerant lines in Pakistan.

Next

It is imperative to build increased yield and climate-resilience to into future germplasm in order to avoid the risk of climate-related crop failure and to maintain global food security in a warmer climate. Partnerships like HeDWIC and IWYP give hope to meeting this urgent food security challenge.

 Further readings:

https://www.hedwic.org/resources.htm

https://iwyp.org/publications

https://royalsocietypublishing.org/doi/full/10.1098/rspb.2012.2190

An economist’s perspective on plant sciences: Under-appreciated, over-regulated and under-funded

Get a new view: attend an interdisciplinary conference

When I first volunteered to write a blog about the Plant Wax 2015 conference, I thought I’d be writing about its relevance to the Global Plant Council’s stress resilience initiative. After all, the waxy coating (cuticle) that covers the aerial surfaces of plants is particularly important as a barrier against water loss and pathogens, while reflecting excess heat and UV radiation.

As it turns out, one of the most important lessons I learned from the meeting was a reminder of the powerful synergy that can happen when people with radically different goals and approaches get together to share ideas.

Water drops on a leaf

Plants are coated with a hydrophobic waxy covering known as a cuticle. Image credit: Adrian Scottow. Licensed under: CC BY-SA 2.0.

A meeting of two worlds

Biologists are from Venus, organic geochemists are from Mars

In the run up to the meeting, held 16–19 June 2015 in beautiful Ascona, Switzerland, I realized that the majority of speakers and delegates were organic geochemists, rather than plant scientists like myself. Other than brief discussions with the academics in the University of Bristol’s School of Chemistry I hadn’t had much interaction with this area of research, so didn’t really know what to expect.

Plant biologists are interested in cuticular waxes because of their impact on the physiology of the plant. The cuticle is composed of many different types of compounds, including alkanes, alcohols, aldehydes, ketones and esters, to say nothing of the more complicated compounds I learnt about at the conference (triterpenoids, anyone?). Each compound gives the wax certain characteristics, making it more suited to a particular environment, or to enhancing a particular function. Many of these changes, however, are yet to be fully understood.

 

The structure of the cuticle

The cuticle is formed of hydrophobic wax compounds on a scaffold of cutin (a polyester polymer), topped with a layer comprising only wax. Image credit: Yeats and Rose, 2013. Plant Physiology.

 

Organic geochemists, on the other hand, extract plant waxes from soils, sediments and rocks and analyze them as an integrated signal to cleverly reconstruct past climates. They typically investigate n-alkanes, the simplest straight-chain compounds found in waxes, which are least likely to break down over time. Amazingly, they can look at the ratio of deuterium (heavy hydrogen, 2H) to normal hydrogen (1H) in the n-alkanes to work out the plants’ source of water, or the ratio of 13C to 12C to work out whether the majority of plants at that time were using C3 or C4 photosynthesis.

The Plant Wax conference was organized to try and bring these two very different groups together, encouraging communication and crossover between research fields, and specifically, to answer the question: what could we learn from each other?

 

Leaf fossil

Plant waxes can be preserved in fossils, but organic geochemists typically look at sediments and sedimentary rocks. Image credit: James St. John. Licensed under CC BY 2.0.

Interdisciplinary cooperation

At the start of the conference, I don’t think the majority of biologists had much knowledge of the finer details of organic geochemistry. Likewise, many geochemists said they only had a general overview understanding of wax biosynthesis and plant physiology. The two fields have very little crossover in the scientific literature.

Since geologists’ isotope studies are based on generalizations made from modern biological studies in a few plant species, the geologists had several requests for biologists. Firstly, to improve climate reconstructions, they asked for more biological data!

The geochemists asked the biologists whether there was anything they could help us with. It was quite hard for me to imagine how their methods – environmental reconstructions of the past based on biological studies – could help us with modern plant biology.

In fact, I felt a little smug. I’d been feeling decidedly ignorant while hearing about ingenious geochemistry research, so I almost felt vindicated: did they need us more than we needed them?

It wasn’t until the last day of the conference that I realized just how wrong I was.

Dr Nikolai Pedentchouk

Dr Nikolai Pedentchouk

One of the last talks was by Dr Nikolai Pedentchouk, University of East Anglia, UK. He’s a collaborator of Amelia Frizell-Armitage, my fellow Global Plant Council New Media Fellow, and works on wheat waxes from an organic geochemist’s perspective.

Nikolai described his research into carbon and hydrogen isotopes in the waxy compounds of glaucous (dull blue-ish grey wax) versus non-glaucous (glossy green) wheat: “I used a field set-up to investigate several issues that are of interest to palaeoecologists and palaeoclimatologists and potentially to plant biochemists. We really wanted to know whether differences in leaf wax composition or amount resulted in differences in the isotope values of individual compound classes”.

How could this isotope research be useful to biologists? Amazingly, it could be used to elucidate the biosynthetic pathways for the different compounds in wheat wax – something that has so far not been possible using standard biological techniques.

“When plants synthesize organic compounds they fractionate stable isotopes, for example 13C vs. 12C and 2H vs. 1H. By measuring the isotopic composition of individual compound classes we could potentially reconstruct the order of reactions that could have led to the biosynthesis of a particular compound”, explained Nikolai.

Glaucous and non-glaucous wheat wax crystals

Wax crystals of glaucous (dull blue-ish grey) and non-glaucous (glossy) wheat wax crystals, taken on a scanning electron microscope. Image credit: Amelia Frizell-Armitage.

New perspectives

Nikolai’s application of geochemical techniques to solve a biological problem really opened my eyes to the innovations that can be made when people from vastly different research backgrounds work together and share ideas. Whether its using quantum mechanics to improve our understanding of photosynthesis, or chemical and computational modeling to advance synthetic biology, interdisciplinary collaboration is driving plant science research forwards, and I encourage you all to think outside your research box too!

Increasing Food Production in a Changing World

The fifth report of the International Panel on Climate Change (IPCC) published last year announced that climate change is already negatively affecting our food supply and this problem is only going to be amplified in coming decades.

Our climate is projected to warm by 5ºC by 2050, with increased incidence of extreme weather events. Coinciding with this is a rapidly rising global population, predicted to reach 9.6 billion by 2050. Feeding all these extra mouths is challenge enough. Doing this under changing weather and climate conditions becomes even more difficult.

Food shortages resulting from population growth or unusual weather events can lead to rising food prices and political instability. A global rice shortage in 2008 saw prices rise by over 50%, resulting in riots in Asia and Africa. We might expect events such as this to become more common in the future as the food supply becomes more and more affected by climate change.

Not surprisingly food security is currently a buzz word in the research community, and many resources are being poured into trying to ensure a stable food supply for future generations.

Some climate skeptics argue that increases in carbon dioxide could boost plant growth, resulting in higher yielding plants under climate change. However, the reality is that any positive effect the increased CO2 could have on plant growth is likely to be outweighed by higher temperatures and extreme weather events.

Since the IPCC report there have been a number of studies focussed on the staple food crop wheat, and how yields could be affected in the future.

Wheat

Wheat was first domesticated 10,000 years ago and is now grown more widely than any other crop. Photo by jayneandd used under CC BY 2.0.

Wheat yields are sensitive to temperature, and are predicted to fall by around 6% for every 1ºC rise in temperature. If we do not cut down current emissions, the earth could warm by 5ºC by 2050, equating to a 30% reduction in wheat yields due to temperature increases alone.

This 30% reduction in yield is only the tip of the iceberg. Yields could be further reduced by increased instances of disease epidemics. For example, Fusarium Ear Blight is a wheat disease that causes spikelet bleaching and enhanced senescence. A severe epidemic can wipe out 60% of a wheat crop. In order to take effect, the disease requires wet weather at flowering, something which we can expect to happen more often in the future according to climate models.

Extreme weather events, such as flooding, are predicted to increase over the coming decades, and will cause unavoidable crop losses. This will exacerbate problems with declining yields, further increasing the difficulty of feeding a growing population.

What can we do?

Primarily, we should be trying to limit the extent of climate change, and to do so we need to act now. Reducing emissions and moving to sustainable energy sources should be at the top of the agenda.  However, most climate scientists agree that even if we act now to reduce our emissions, there will be at least 2ºC of warming, which is already impacting on food production.

We therefore need to make our food sources more resilient to climate change. In terms of wheat this means breeding varieties that are tolerant to higher temperatures and diseases. Additionally, we will need to adapt our farming methods, to be more intensive yet sustainable, and perhaps alter our diets.

Stress Resilience Forum, 23–25 October, Iguassu Falls, Brazil

In October the Global Plant Council, in collaboration with the Society of Experimental Biology, will bring together experts from around the world to discuss current research efforts in plant stress resilience. Abstract submission and registration for the Stress Resilience Forum is now open, and we welcome researchers at all levels to take part.

The meeting takes place immediately before the International Plant Molecular Biology Conference (25–30 October), also at Iguassu Falls, and which also includes several scientific sessions on plant stresses.