HARNESSING PLANTS FOR THE FUTURE
“Our world is at a crossroads... Our action or inaction will determine our fate.”
Joanne Chory Director, Plant Molecular and Cellular Biology Laboratory HARNESSING PLANTS FOR THE FUTURE
CONSIDER THIS:
By making the planet 2% more efficient, we can help solve the problem. Get ready, sunny San Diego: Winter is coming.
We’re not talking about a new season of Game of Thrones—although the story is one of epic proportions and high stakes.
Salk Institute scientists will soon have the ability to control the weather, to create at will frigid
Increased CO2 emissions northern winters, baking desert summers and steamy jungle monsoons. In fact, they will be able to simulate nearly any climate on Earth in a state-of-the-art plant research facility slated to begin operation in November 2017.
In the facility’s high-tech grow rooms and chambers, Salk’s plant biologists will put plants through intense paces, subjecting them to temperature, light and moisture conditions that mimic everything from Spanish summers to Swiss winters. The new facility anchors the Institute’s Harnessing Plants Initiative, an ambitious effort launched this fall to develop Effects from global warming biology-based solutions to the urgent challenge of global climate change, one of the most serious threats facing humanity.
“Our world is at a crossroads,” says Joanne Chory, director of Salk’s Plant Molecular and Cellular Biology Laboratory, Howard Hughes Medical Institute (HHMI) investigator and mastermind of the initiative. “Over the next fifty years, the human population will grow to around 10 billion people. Right now we have 7 billion people and we have already strained the planet’s ability to support us. Our action or inaction will determine our fate.” Burgeoning population Chory, who holds the Howard H. and Maryam R. Newman Chair in Plant Biology, and her colleagues have chosen action. Over the past decades, Salk’s plant biology team has emerged as a world leader in pioneering discoveries about the inner workings of plants. They have illuminated the molecular machinery inside plant cells that allows them to grow, survive stress and adapt to new environments. Now, Chory and her colleagues plan to apply their hard-won foundational knowledge of plant biology to the practical purpose of addressing the myriad disruptions posed by global warming. Stressed crops The Harnessing Plants Initiative hinges on developing “ideal plants®” to help tackle the critical and interlinked challenges of human emissions of carbon dioxide, declining agricultural yields and collapsing ecosystems. At the same time, these ideal plants will help meet the burgeoning demands of a rapidly growing human population for plant products.
Collapsed ecosystems Salk has a two-pronged solution:
1. 2.
Use “ideal” terrestrial crop plants to Maintain sequestration capacity Increased demand for capture a significant portion of human- of coastal marine environments by food, fuel, feed and fiber emitted CO2. reversing seagrass loss. SOLUTION 1: Breaking the cycle Utilizing suberin to store more carbon without releasing it.
Suberin = Cork THE 3-IN-1 SOLUTION 1. 2. 3.
CO2 CO2
Plants are naturally Store carbon stably in Increase environmental Feed the world Ideal plants will produce very good at sequestering ® roots (or root systems) stress tolerance. sustainably. more suberin which removes carbon; they have been deep in the soil. - No tilling CO from the atmosphere, doing it for millions of years. 2 - Less fertilizer revitalizes ecosystems and improves agriculture. Carbon Conundrum double,” says Chory. “This puts human consumption and global warming on a Life on Earth begins and ends with carbon. dangerous collision course.” The stuff of life—proteins, carbohydrates, lipids and DNA—is built on a carbon Many efforts are under way to reduce backbone. Life emerged around three the amount of carbon we emit, but billion years ago and has since evolved these initiatives have run into political, into billions of species. The vast majority economic and technological obstacles. of species that have existed have since It has become clear, says Chory, that gone extinct. Interred in the earth ages solely focusing on reducing emissions ago, certain forms of life—plants and won’t solve the problem. We simultaneously algae, in particular—left behind enormous need to focus on removing the carbon concentrations of carbon: coal, petroleum that has accumulated in the atmosphere. and natural gas. Carbon made life By developing specialized crops capable possible, and the end of uncounted of adapting to a changing climate, Chory lives made concentrated, energy-rich and her colleagues believe they can carbon abundantly available for the most substantially increase the amount of enterprising of species, Homo sapiens. carbon captured and stored in the planet’s soils. At the same time, they plan to Since the dawn of the Industrial Revolution, identify varieties of seagrasses to maintain humans have become very good at and restore coastal aquatic ecosystems, exhuming the remains of our carbonized where massive amounts of carbon are predecessors for use as energy to power stored in the roots of these grasses. our modern societies. Too good, it seems. Over the past century, the concentration of greenhouse gases in the atmosphere has Corking Carbon steadily increased, mostly from burning fossil fuels. Currently, humans emit around Plants are excellent at scrubbing carbon 35 gigatons of carbon dioxide into the from the atmosphere. Every year, the atmosphere annually through industry, world’s plants breathe in around 64
“Our world is at transportation, electricity generation and gigatons of CO2 from the air, storing the a crossroads... other activities. Greenhouse gases prevent carbon in leaves, shoots and roots. To get light from the sun from reflecting back into a sense of the staggering amount of carbon Our action or space, effectively trapping heat. The result plants absorb, consider that an adult inaction will has been a 1.5-degree increase in average African elephant at the San Diego Zoo can global surface temperature since the late weigh up to 6.8 metric tons. One gigaton determine our 19th century—global warming. is equivalent to more than 100 million of fate.” those elephants. Now multiply by 64. The impact of this warming is unmistakable. The polar ice caps are melting with While plants store this carbon in the alarming rapidity and the oceans are form of numerous biomolecules, almost Joanne Chory swelling as they warm. Both factors all of these materials are degraded by Professor and Director raise sea level, which threatens coastal animals, fungi and bacteria and the Plant Molecular and communities with erosion and flooding, stored CO thereby released. The Salk Cellular Biology Laboratory 2 and the warming oceans fuel massive team has identified one particular plant- storms and extreme weather. Recent made molecule, called suberin, that is summers have been the hottest and highly resistant to this degradation and driest on record, resulting in increasing can thereby remain in the soil. Suberin, numbers of forest fires. better known to wine aficionados as cork, is a waxy, water-repellant and carbon-rich The same conditions are suppressing substance, and is at the heart of the Salk global agricultural yields, a trend that team’s strategy to address the problem is likely to worsen if predictions of an of meeting human needs while reducing additional global warming of 2 to 3 carbon in the atmosphere. Each growing degrees over the next few decades season, annual crops—plants that live prove accurate. “The human population only one season, such as corn or wheat—
will grow by around 40 percent over the breathe in CO2 to build plump leaves, tall next 50 years and the middle class may stems and thick roots. Joseph Noel Joseph Ecker Julie Law
Uncovered the blueprints used Led sequencing of the first plant genome Identified mechanisms by plants to produce chemical and mapped the first plant epigenome for epigenetic regulation compounds
At the end of the season, the plants die Increasing the amount of suberin each their quest to develop the ideal plant, the and rot, releasing much of that carbon cell produces is one strategy; another is Salk team will experiment with both Lotus back into the atmosphere. to increase the number of cells—in other and Arabidopsis thaliana, the common words, to grow larger roots. In both mustard weed that is the predominant “What if you could tweak this carbon cases, the newest addition to Salk’s plant research model. Much of what cycle in the plant so that it absorbed plant biology team, Associate Professor scientists know about the fundamentals more carbon and released less?” says Wolfgang Busch, is providing critical of plant molecular and cellular biology has Joseph Noel, a member of Salk’s plant expertise. Busch combines techniques come from studying Arabidopsis. Adding biology team and Howard Hughes from genetics, genomics and other Lotus to the research mix will allow the Medical Institute investigator. science fields to understand how Salk team to expand its research to focus root growth in given environments is on a plant more closely related to crops. “We realized that a crop with a larger, determined by a plant’s genes. This is important to the Harnessing Plants suberin-dense root would capture more Initiative, as the carbon-capturing plants carbon in the ground,” he says. “Roots “There is still a great deal we don’t the Salk team is designing would need to last longer than other parts of plants, know about how genes and molecular be food-producing crops deployed at a particularly in perennial plants that live mechanisms determine how a plant root scale sufficient to put a significant dent multiple years. Even in dead roots, decides to grow to a certain size or in in global warming. suberin decays very slowly.” a certain direction in the soil,” Busch says. “To breed crops with large roots “Most of the world’s arable land is already Carbon stored in suberin could that produce a lot of suberin, we’ll being used for agriculture, and we are potentially stay in the soil for hundreds need a better understanding of how already straining our natural ecosystems or even thousands of years. So you to influence both aspects at the genetic and our capacity to generate food and have two possible benefits: store more and molecular level.” other plant products,” says Busch. carbon and store it for a long time. An “A legume crop bred with a large root expert on the structure and chemistry In addition to his expertise, Busch brought could be planted on farms around the of compounds produced by plants a plant with him to Salk: Lotus japonicus. world and could potentially have multiple and on how plants have evolved unique A native plant of Japan, known commonly advantages over current crops.” ways to make their own specialized in English as birdsfoot trefoil, Lotus is a wild products to adapt to nearly every legume that has become the laboratory Deploying an “ideal” legume crop on ecosystem on Earth, Noel is exploring stand-in—a “model organism” in scientific a relatively small portion of the world’s how plant cells can be coaxed to parlance—for studying the biology of all farmland could capture a significant produce more suberin—and thus legumes, a group of plants that includes portion of global CO2 emissions. Among capture more carbon. chickpeas, beans, peanuts and lentils. In the other advantages of legumes is that Salk’s World-Class Plant Biology
Joanne Chory Wolfgang Busch Team
Discovered multiple pathways that Identified multiple key genes for regulate plant form and size in response regulating root growth to the environment crops could be perennials, surviving and climates ranging from arid regions of “To breed crops producing year after year, which avoids northern Africa to temperate northern annual replanting. The roots would remain Europe. In Japan, Lotus grows from with large roots undisturbed, keeping the plant’s carbon tropical Okinawa to frigid Hokkaido, that produce a lot haul locked underground. Legumes also the northernmost of the country’s tend to make friends. Most grow nodules major islands. of suberin, we’ll on their roots as homes for bacteria called need a better rhizobia, which convert nitrogen from Julie Law, another member of the Salk the air into usable forms the plants need plant biology team, says the natural understanding of to thrive. This is why farmers include variation that allows plants to live in legumes in crop rotations with other plants very different conditions is a kind of how to influence to help replenish soil nitrogen. The crops evolutionary playbook that the Harnessing both aspects at envisioned by the Salk team thus require Plants Initiative can draw from. “As plants less fertilizer than normal crops, reducing spread and adapted to new conditions, the genetic and the harmful farm run-off that damages they evolved new survival skills,” says Law, molecular level.” aquatic ecosystems. an assistant professor at Salk. “We can learn from these plants to design crops that will be highly adaptable and can grow Wolfgang Busch Learning from Nature in a range of climates.” Salk plant biology professor
Salk’s new plant growth facility will be For instance, the climate of the Midwest, critical to finding ways to turn crops into the traditional breadbasket of the United carbon warehouses. Just as important, States, is becoming hotter and drier. At it will help the researchers find ways to the same time, flooding due to heavier grow plants in a variety of conditions. rains has increased. Looking globally, a Plants are highly attuned to specific 2016 study estimated that drought and climates, and subtle variations in extreme heat reduced worldwide crop temperature, rainfall, humidity and soil yields by as much as 10 percent between salinity can have a serious impact on 1964 and 2007. Many plants developed their growth. Even within a species, to capture and store large amounts of plants can prefer very different carbon will need to be heat and drought environments. Arabidopsis, for instance, tolerant to thrive. Resilience to flooding grows naturally around the globe, in might also come in handy, as extreme SOLUTION 2: An unexpected ally
Coastal marine plants can be transformative.
Climate Adaptive Restore global food-producing ecosystems.
30X Greater Carbon Restoration Fishery Breeding Storage Grounds Carbon Capture Boosting carbon-storage Better understanding of Seagrasses are essential capacity of seagrasses is key seagrass biology will enhance to healthy fisheries such Use coasts to capture and to fighting global warming. ecosystem restoration. as coral reefs. store for millennia. rain events and resulting floods are also repositories of the planet’s carbon. Coastal a growing threat to crops. By collecting seagrass beds store nearly twice as much varieties of Arabidopsis and Lotus from carbon per acre as terrestrial forests a range of different climates, then growing and account for about 10 percent of the them under hot, dry conditions in the carbon stored in the ocean. Unfortunately, new climate simulation facility at Salk, due to dredging and pollution, seagrass the Institute’s plant biologists can identify ecosystems are seriously threatened the plants best adapted to that situation. around the world. About 1.5 percent of They can look for what makes plants these ecosystems disappear each year. resistant to flooding or cold snaps—or Changing water temperatures due to global any other climate threats that seem to warming accelerates this decline. As they be increasing in frequency. They can go, so goes a range of important functions then analyze the genetic and molecular they serve: carbon sequestration, habitat makeup of these plants to find out what for fish, and storm and flood protections makes them durable, and use what for coastal communities. they find to breed those traits into their “ideal plants.” Maintaining existing seagrass ecosystems and restoring others, says Noel, offers a “The ideal plant doesn’t just capture clear-cut solution to addressing climate carbon and produce food,” says Law. change. Similar to land plants, seagrasses “It also grows where you want it to grow. grow in a range of climates, so as water As climate changes, many regions are conditions change and kill off grasses in a becoming hotter and drier, but others region, scientists can draw from the natural are getting colder and wetter. We need variation to identify replacements from a toolbox of adaptive traits to draw from.” other areas that are more likely to survive the new normal. A tropical seagrass, for In addition to identifying key genetic instance, might grow well in an area where traits for developing ideal plants, Law temperate waters are warming. Another and Joseph Ecker, another Salk professor tactic might be to restore ecosystems with and HHMI investigator, are searching carbon-hungry varieties of seagrasses. “The essence of for key patterns of epigenomic modifications, chemical changes that “Certain varieties of seagrass have greater climate change alter a plant’s genetic activity without carbon storage capacity,” adds Noel. from a plant’s changing the letters of the DNA alphabet “If this trait was bred into other varieties (A-T-C-G). These patterns have allowed of grasses, we could sequester far more perspective is plants in nature to adapt to various carbon in coastal ecosystems.” responding to environments, and will likely be crucial to developing the ideal plants envisioned The Salk team plans to identify what stress.” by the Salk team. traits make certain seagrasses suited to various ecosystems, and to use that “The essence of climate change from knowledge to identify what varieties Joseph Ecker a plant’s perspective is responding to could be transplanted to ecosystems Salk plant biology professor stress, because changes in the plant’s where climate change is killing grasses. environment can represent an existential Restoring compromised aquatic threat,” says Ecker. “Developing a ecosystems would have the double thorough understanding of the genetic benefit of capturing more carbon in and epigenetic mechanisms that control the sea and reestablishing ecosystems, plants’ stress responses will allow us such as coral reefs, that support fisheries.” to develop crops that are more resilient and precisely suited to specific climate “That’s the beauty of both our terrestrial regimes.” and our aquatic strategies,” says Noel. “They address the food problem and the climate change problem simultaneously, An Aquatic Ally on the land and in the water. We humans are going to need to be very smart to get In addition to land plants, the Salk through the next century, and that means team plans to extend their research developing strategic solutions based on to seagrasses, one of the other major good science.” At Salk, we study plants so humans will have the food, clothing, energy and medicines they need now and in the future. Your tax-deductible support helps Salk scientists better understand plants deep down—from their root systems to their epigenome.
To learn more about Salk’s Harnessing Plants Initiative, and to donate now, contact Brent Wakefield, senior director of External Relations, at (858) 453-4100 x1556 or [email protected].
Salk Institute for Biological Studies 10010 N Torrey Pines Rd La Jolla, California 92037-1002 Telephone: (858) 453-4100 www.salk.edu