Researchers at the University of Illinois are unlocking the full potential of a problematic compound found in plant growth to create a shortcut aimed at boosting crop yields that are 40 percent more productive, a possible breakthrough to potentially tackle global food supply demand and insecurity.

Plants convert sunlight via photosynthesis, but most plants on the planet deal with an issue known as the photosynthetic glitch. The glitch, as part of a high-energy process, comes from how the enzyme rubisco will “grab” oxygen from the atmosphere about 20 percent of the time, producing a compound called glycolate that can’t be used in sugar production and ultimately plant growth, according to Realizing Increased Photosynthetic Efficiency (RIPE) Director and U of I Crop Sciences and Plant Biology Chairperson Stephen Long.

Long said in an interview with States of Life computer modeling suggested the glitch, and the process as explained above, known as photorespiration, found plants evolved to recycle the compound, while the process was found to reduce soybean yields in the Midwest by as much as 36 percent and can get worse in hotter and arid climates.

Researchers from the U of I and U.S. Department of Agriculture (USDA) Agricultural Research Service developed three photo respiratory shortcuts, engineering crops that produced 40 percent greater yield in practical agricultural production.

According to Agricultural Research Service molecular biologist Dr. Paul South, the need to develop more efficient crops is not only important, but vital to meeting future food demand around the world.

The United Nations Food and Agriculture Organization (UN-FAO) estimates the need for 60 percent more food around the world by 2050. According to the project, in the wake of widespread famine, the last century saw plant scientists breeding a new generation of plants to feed millions of hungry people across the world. For decades, this enabled food production to rise in scale with population growth. But those advances have reached their biological limits and new innovations will be crucial to keep pace with this century’s growing population: 8.5 billion by 2030, 9.7 billion by 2050, and 11.2 billion by 2100.

“Should the world need less than the UN-FAO estimate being able to produce more food per unit of land, will allow a reduction in the agricultural footprint,” South told States of Life.

Long said two shortcuts have been previously developed, and the third “and most successful” was engineered to improve upon the previous shortcuts.

“I used the DNA sequence of a gene from green algae and plant DNA that is normally only expressed when seeds are germinating installing them into the leaves of tobacco plants,” Long said. “The reason we used tobacco is because it is fast growing, has a short life cycle, produces a large amount of seed and can be grown in a field like other crops.”

Tobacco is a commonly used model crop in laboratory and field experiments.

Long believes the success of the recent shortcut lies in the amount of energy needed to convert glycolate, noting it could be lower versus natural photorespiration. The team’s research appears to show the shortcut could possibly increase CO2 concentration in the chloroplast which could decrease the likelihood that rubisco grabs oxygen instead of CO2.

“How the shortcut effects all plant metabolism is an interesting area of research we are currently looking into,” Long said.

South said the team hopes to transfer the innovation to food crops, deregulation at the federal level within the USDA, Environmental Protection Agency (EPA), and Food and Drug Administration (FDA), along with using the research to breed into appropriate genetic backgrounds and then multiplication to provide sufficient seed supply for wide use by farmers. The latter process would require about two decades of application under current regulations and methods, showing the evident need to deregulate to protect against global hunger.

RIPE is an international research project that is engineering plants to photosynthesize more efficiently to increase the yields of staple food crops and improve global food security. The goal is to equip farmers worldwide with higher-yielding crops to increase income and opportunities. 

Stephen Long is a Distinguished Professor of Crop Sciences at Lancaster University in the United Kingdom. Steve’s research has increased our understanding of how global climate change is affecting plants and is helping to inform approaches to increase crop yields by improving the efficiency of photosynthesis. His expertise ranges from plant molecular biology to in silico crop design and field analyses of the impacts of atmospheric change on crops. 

Dr. Paul South’s expertise covers molecular genetics, molecular biology and biochemistry. More specifically, he focuses on epigenetic regulation of gene expression. For the RIPE project, he is improving photorespiratory bypass by identifying and down-regulating chloroplast inner membrane proteins necessary for export of photorespiratory products, such as glycolate.