Wheat and other edible grasses have developed pores that make them more drought tolerant. Stanford scientists have studied these pores with an eye toward future climate change.
These plants, which make up about 60 percent of the calories people consume worldwide, have a modified stoma that experts believe makes them better able to withstand drought or high temperatures. Stanford University scientists have now confirmed the increased efficiency of grass stomata and gained insight into how they develop. Their findings, reported in the March 17 issue of Science, could help us cultivate crops that can thrive in a changing climate.
“Ultimately, we have to feed people,” said Dominique Bergmann, professor of biology and senior author of the paper. “The climate is changing and, regardless of the cause, we’re still relying on plants to be able to survive whatever climate we do have.”
Adjusting an ancient system
Grasses – which include wheat, corn and rice – developed different stomata, which may have helped them spread during a prehistoric period of increased global dryness. Stomata usually have two so-called “guard cells” with a hole in the middle that opens and closes depending on how a plant needs to balance its gas exchange. If a plant needs more CO2 or wants to cool by releasing water vapour, the stomata open. If it needs to conserve water, they stay closed.
The protein in yellow moves out of the guard cells into cells on both sides. By recruiting these cells, grass stomata become better suited to hot and dry environments.
Grasses improved on the original structure by recruiting two extra cells on either side of the guard cells, allowing for a little extra give when the stoma opens. They also respond more rapidly and sensitively to changes in light, temperature or humidity that happen during the day. Scientists hope that by knowing more about how grass developed this system, they may be able to create or select for edible plants that can withstand dry and hot environments, which are likely to become more prevalent as our climate changes.
“We take our food and agriculture for granted. It’s not something the ‘first world’ has to deal with, but there are still large areas of the world that suffer from famine and this will increase,” said Michael Raissig, a postdoctoral researcher in the Bergmann lab and lead author of the paper. “The human population is going to explode in the next 20 to 30 years and most of that is in the developing world. That’s also where climate change will have the biggest effect.”
Growing a better mouth
Scientists have assumed grasses’ unusual stomata make these plants more efficient “breathers.” But, spurred by curiosity and a passion for developmental biology, these researchers decided to test that theory.
Thanks to a bit of luck, they found a mutant of the wheat relative Brachypodium distachyon that had two-celled stomata. Partnering with the Berry lab at the Carnegie Institution for Science, the group compared the stomata from the mutant to the normal four-celled stomata. They not only confirmed that the four-celled version opens wider and faster but also identified which gene creates the four-celled stomata – but it wasn’t a gene they expected.
“Because it was a grass-specific cell-type, we thought it would be a grass-specific factor as well,” said Raissig, “but it’s not.”
Instead of relying on a completely new mechanism, the recruitment of the extra cells seems to be controlled by a well-studied factor which is known to switch other genes on and off. In other plants, that factor is present in guard cells, where it is involved in their development. In grasses, the team found that the factor migrated out of guard cells and directly into two surrounding cells, recruiting them to form the four-celled stomata.
Feeding the world
Over evolutionary time, humans have bred and propagated plants that produce the kinds of foods we like and that can survive extreme weather.
“We’re not consciously breeding for stomata but we’re unconsciously selecting for them,” said Bergmann, who is also a Howard Hughes Medical Institute investigator. “When we want something that’s more drought resistant, or something that can work better in higher temperatures, or something that is just able to take in carbon better, often what we are actually doing is selecting for various properties of stomata.”
The adaptability and productivity of grass makes understanding this plant family critical for human survival, the scientists said. Someday, whether through genetic modification or selective breeding, scientists might be able to use these findings to produce other plants with four-celled stomata. This could also be one of many changes – to chloroplasts or enzymes, for example – that help plants photosynthesize more efficiently to feed a growing population.
“Organic is often proposed a holy grail solution to current environmental and food scarcity problems, but we found that the costs and benefits will vary heavily depending on the context,” said Verena Seufert, a researcher at the Institute for Resources, Environment and Sustainability (IRES).
In their study, Seufert and her co-author Navin Ramankutty, Canada Research Chair in Global Environmental Change and Food Security at UBC, analyzed organic crop farming across 17 criteria such as yield, impact on climate change, farmer livelihood and consumer health.
It is the first study to systematically review the scientific literature on the environmental and socioeconomic performance of organic farming, not only assessing where previous studies agree and disagree, but also identifying the conditions leading to good or bad performance of organic agriculture. [Explore their findings in-depth in this image]
Take two factors that are top of mind for many consumers: synthetic pesticide use and nutritional benefits of organic. Seufert and Ramankutty argue that in countries like Canada where pesticide regulations are stringent and diets are rich in micronutrients, the health benefits of choosing organic may be marginal.
“But in a developing country where pesticide use is not carefully regulated and people are micronutrient deficient, we think that the benefits for consumer and farm worker health may be much higher,” said Ramankutty, professor at IRES and the Liu Institute for Global Issues at UBC.
Another important measure of the sustainability of farming systems is the yield of a crop. To date, most studies have compared the costs and benefits of organic and conventional farms of the same size, which does not account for differences in yield.
Previous research has shown that on average, the yield of an organic crop is 19 to 25 per cent lower than under conventional management, and Seufert and Ramankutty find that many of the environmental benefits of organic agriculture diminish once lower yields are accounted for.
“While an organic farm may be better for things like biodiversity, farmers will need more land to grow the same amount of food,” said Seufert. “And land conversion for agriculture is the leading contributor to habitat loss and climate change.”
While their findings suggest that organic alone cannot create a sustainable food future, they conclude that it still has an important role to play. Buying organic is one way that consumers have control over and knowledge of how their food is produced since it is the only farming system regulated in law.
“We need to stop thinking of organic and conventional agriculture as two ends of the spectrum. Instead, consumers should demand better practices for both so that we can achieve the world’s food needs in a sustainable way,” said Seufert.
MFGA's timing bodes well given last week's call by Sustainable Development Minister Cathy Cox for input into a Manitoba Climate and Green Plan for Manitobans to have their say on the carbon pricing plan being imposed by the federal government. The key takeaway point of the MFGA position is the MFGA's advocacy for the plants above the soil and the microbial activity below, looping forages, grasslands, cover crops and annual crops as positives on the carbon front.
The MFGA recommends that the following needs should be addressed with regards to understanding and promoting carbon sequestration in grasslands, forages, cover crops and annual crops and the soils they grow in:
1. As a producer-led group, MFGA should be involved in all policy and partnership discussions around carbon sequestration and other ecosystem services provided by well-managed forage and grasslands, cover crops and annual crop production.
2. Soil carbon benchmarking and monitoring should be done across the Manitoba agricultural lands and the potential benefits of increased soil carbon on a landscape scale should be modelled.
3. Research and testing for Manitoba producers needs to be conducted within Manitoba to quantify the amount of carbon sequestered across a variety of landscapes using forage and grasslands as well as cover crops and perennial stages in crop rotation.
4. Reward or compensation should be provided for producers who are able to retain or restore forages and grasslands and/or manage their soils to store and sequester carbon via incentive programs such as Alternative Land Use Services. This also applies to any other ecosystem services (water retention, flood prevention, biodiversity, etc.) that forages, grasslands and soils provide to society from Manitoba's agricultural lands.
5. The MFGA Aquanty Project Model for the Assiniboine River Basin should be used to run simulations for demonstrating the role that organic carbon stored under forages and grasslands plays in flood and drought mitigation. The MFGA Aquanty Project is on schedule for completion March 2018.
6. Rotational grazing, cover crops and zero-till farming practices for soil health should continue to be supported and promoted by government and industry.
7. An emphasis needs to be placed, in policy and public communications, on the positive linkages of livestock production, well-managed grasslands and sustainably-managed crop lands to soil health, carbon sequestration and other ecosystem services.
Research published in Bioscience suggests that production likely will need to increase between 25 percent and 70 percent to meet 2050 food demand. The assertion that we need to double global crop and animal production by 2050 is not supported by the data, argues Mitch Hunter, doctoral student in agronomy, in Penn State's College of Agricultural Sciences. He says the analysis shows that production needs to keep increasing, but not as fast as many have claimed. | READ MORE
While drones have a foothold in the game of precision agriculture, some researchers are toying with the idea of using them as pollinators as well.
Researchers ordered a small drone online and souped it up with a strip of fuzz made from a horsehair paintbrush covered in a sticky gel. The device is about the size of a hummingbird, and has four spinning blades to keep it soaring. With enough practice, the scientists were able to maneuver the remote-controlled bot so that only the bristles, and not the bulky body or blades, brushed gently against a flower’s stamen to collect pollen – in this case, a wild lily (Lilium japonicum). To ensure the hairs collect pollen efficiently, the researchers covered them with ionic liquid gel (ILG), a sticky substance with a long-lasting “lift-and-stick-again” adhesive quality – perfect for taking pollen from one flower to the next. What’s more, the ILG mixture has another quality: When light hits it, it blends in with the color of its surroundings, potentially camouflaging the bot from would-be predators. | READ MORE
By using a clever combination of two inexpensive additives to the spray, the researchers found they can drastically cut down on the amount of liquid that bounces off. The findings appear in the journal Nature Communications, in a paper by associate professor of mechanical engineering Kripa Varanasi, graduate student Maher Damak, research scientist Seyed Reza Mahmoudi, and former postdoc Md Nasim Hyder.
Previous attempts to reduce this droplet bounce rate have relied on additives such as surfactants, soaplike chemicals that reduce the surface tension of the droplets and cause them to spread more. But tests have shown that this provides only a small improvement; the speedy droplets bounce off while the surface tension is still changing, and the surfactants cause the spray to form smaller droplets that are more easily blown away. | READ MORE
“The research indicates that there may be economic benefits to farmers under specific field conditions”, says Gord Green, President of OSCIA. “Under drought conditions, research has confirmed as high as a 25 per cent increase in corn yield where controlled drainage was used to retain water to better supply the growing crop.”
Research shows the benefits from controlled tile drainage vary depending on the crop, amount of rainfall, and timing of rainfall in relation to the stage of crop growth. Under the new partnership, a new tool will be developed to allow extension staff and farmers to better calculate the crop yield benefits of controlled tile drainage under varying conditions.
“With extremes in weather increasing due to climate change, every competitive edge counts”, says Dr. Michael Sawada, scientist at the University of Ottawa. “Additionally, controlled drainage can reduce the flow of phosphorus and other nutrients to help protect our water resources.”
The collaborative project runs until the winter of 2018.
Funding for the “Controlled Tile Drainage – Calculate Your Benefits” project is provided through Growing Forward 2, AgriRisk Initiatives, which supports the research and development, as well as the implementation and administration of new risk management tools for use in the agriculture sector.
Agriculture has an important role in climate change, and the OFA is advocating for the sector to mitigate impacts as they participate in the Climate Change Action Plan. Also, the OFA is preparing to work on new legislation, like the Waste Free Ontario Act, which will reduce waste and the dependence on rural landfills.
The work on regulations is ongoing. There’s a push for a more effective regulatory system for the agriculture sector. Minister of Economic Development, Employment and Infrastructure, Brad Duguid, has emphasized his parliamentary assistant will pursue Burden Reduction legislation (Bill 218) to modernize and update legislation.
The Minister of Agriculture, Food and Rural Affairs, Jeff Leal, reinforces the need for effective programs and services to rural communities. Other priorities include the importance of economic growth, which will include investing in better infrastructure, affordable education and a competitive low-carbon economy.
For more information, visit ofa.on.ca.
The LandPKS mobile app, which includes the LandInfo and LandCover modules, taps cloud computing, digital and traditional soil-mapping, and GPS data to provide information on the sustainable potential of land under current and future climate conditions.
The current version of the LandInfo module allows the user to collect soil and site topographic data, while the LandCover module is used to document ground cover, vegetation height, plant density, and spatial patterns of vegetation affecting soil erosion. Domestic and international development organizations and land-management agencies are already using the app to crowd-source the local information needed to inform management decisions.
Read the full story here.
“This year’s harvest has been a long, drawn out affair, filled with frustration and disappointment,” said Harry Brook, crop specialist, AF, in a press release. “Many producers still have crop left to be harvested or are taking it off wet, with grain being binned or bagged or piled at unheard of moisture levels. These crops cannot be left out in the cold for extended periods of time unattended.”
Once the crop is harvested and in storage, the excess moisture must be dealt with as soon as possible. “If you don’t have ready access to a grain dryer or have aeration for your bins, you must closely monitor the grain or oilseed for signs of heating. If you see signs that there is heating, you will need to cool the grain by circulating the grain out of and back into the bin. Depending on bin or pile size, this may have to be done fairly frequently.”
Brook has a caution for producers who are using grain bags for short term storage. “Remember that very damp or wet grain in a bag will start to mould. Some moulds will grow at cold temperatures and losses can be high. If bags are used for wet grain storage it should only be short term until crop drying occurs and close monitoring can again begin.”
When drying grain, there are maximum temperatures that should be used on the various crops. “There are tables that outline the maximum temperatures to be used to dry grain. Don’t exceed those maximum drying temperatures to avoid quality losses. With a large amount of moisture to be removed or a big seed, multiple passes of drying and cooling will be needed. In large seed like fababeans, drying might take three or four cycles to bring it down to safe storage levels. The cooling is required to let the moisture content in the seed equalize.”
If there is aeration, some supplemental heat can be used to help dry down the crop. However, Brook said, in this case smaller bins will be more useful than large bins. “To make this work, the fan has to have sufficient air flow to provide at least 0.5 cfm/bushel before adding the supplemental heat. Success will depend on the cleanliness of the grain and, even then, a load or two will have to be circulated out of the bin and back in to help equalize moistures and prevent dry and wet channels in the grain.”
Brook recommends restricting the air temperature increase to 10 C or less as higher temperatures can reduce efficiency and increase the chances of over-drying. For every 10 C increase in air temperature, the relative humidity is halved.
“If you have crop that is damp or wet, monitor it closely for signs of heating and, if it occurs, take the appropriate measures to retain the value of the crop. It is too costly to do otherwise.”
Shallow banding N risks volatilization lossWhat would the late John Harapiak think of this: Nitrogen…
Organic farming not always best for the planetMany consumers think organic is better for humans and the…
New pea processing plant to be built near Portage la Prairie, M.B.A new $400 million pea processing plant is in the…
Banking on edible dry beansWhen Meghan Moran, the canola and edible bean specialist for…
Royal Manitoba Winter FairMon Mar 27, 2017
Employee Selection WebinarMon Mar 27, 2017 @10:00am -
Cultivating the Great Clay Belt Agriculture SymposiumThu Mar 30, 2017
Hiring Employees WebinarMon Apr 03, 2017 @10:00am -
Spring Workshop on Organic ResearchFri Apr 07, 2017 @ 8:30am - 04:00pm