U of I RIPE Team Has Engineered Potato to Be More Resilient to Global Warming

A team from the University of Illinois has engineered potatoes to be more resilient to global warming, showing 30% increases in tuber mass under heatwave conditions.
Given that these are frequently the same regions where the changing climate has already impacted several crop seasons, this adaptation may increase food security for families that rely on potatoes.
“We need to produce crops that can withstand more frequent and intense heatwave events if we are going to meet the population’s need for food in regions most at risk from reduced yields due to global warming. The 30% increase in tuber mass observed in our field trials shows the promise of improving photosynthesis to enable climate-ready crops,” Katherine Meacham-Hensold, scientific project manager for the Realizing Increased Photosynthetic Efficiency (RIPE) at Illinois, mentioned.
Meacham-Hensold oversaw this work for RIPE, an international research effort that seeks to improve food access worldwide by creating food crops that more effectively convert solar energy into food.
The Bill & Melinda Gates Foundation, Foundation for Food & Agriculture Research, and U.K. Foreign, Commonwealth & Development Office assisted RIPE from 2017 to 2023. Bill & Melinda Gates Agricultural Innovations (Gates Ag One) is now providing support for RIPE.
The Challenge
It has been demonstrated that the photosynthetic process of photorespiration can lower vegetable, rice, and soybean yields by as much as 40%. Under optimal circumstances, photorespiration happens about 25% of the time, although it happens more frequently at high temperatures because Rubisco reacts with an oxygen molecule instead of CO2. The poisonous result of photorespiration (glycolate) must then be metabolized by plants, which requires a significant amount of energy, energy that may have been put toward more expansion.
“Photorespiration is a large energy cost for the plant,” said Meacham-Hensold. “It takes away from food production as energy is diverted to metabolizing the toxin. Our goal was to reduce the amount of wasted energy by bypassing the plant’s original photorespiratory pathway.”
Previous RIPE team members had shown that by adding two new genes, glycolate dehydrogenase and malate synthase, to model plants’ pathways, they could improve photosynthetic efficiency. The new genetics would metabolize the toxin (glycolate) in the chloroplast, the leaf compartment responsible for photosynthesis, rather than needing to move it through other regions of the cell.
The Solution
These energy savings drove growth gains in the model crop, which the current team hoped would translate to increased mass in their food crop. Not only did they see a difference, but the benefits, recently published in Global Change Biology, were tripled under heatwave conditions, which are becoming more frequent and more intense as global warming progresses.
Three weeks into the 2022 field season, while the potatoes were still in their early vegetative growth phase, a heatwave kept temperatures above 35°C for four straight days, breaking 38°C twice. After a couple of days of reprieve, the temperatures shot up near 100° again.
Rather than withering in the heat, the modified potatoes grew 30% more tubers than the control group potatoes, taking full advantage of their increased thermotolerance of photosynthetic efficiency.
“Another important feature of this study was the demonstration that our genetic engineering of photosynthesis that produced these yield increases had no impact on the nutritional quality of the potato. Food security is not just about the amount of calories that can be produced but we must also consider the quality of the food,” Don Ort, Robert Emerson Professor of Plant Biology and Crop Sciences and Deputy Director of the RIPE project, added.
Multi-location field trials are needed to confirm the team’s findings in varying environments, but encouraging results in potatoes could mean similar results could be achieved in other root tuber crops like cassava, a staple food in Sub-Saharan African countries expected to be heavily impacted by rising global temperatures.