WUHAN, CHINA – Scientists at Huazhong Agricultural University have identified a natural gene system in rice that increases crop yields by 31-93% under high-temperature conditions, potentially addressing food security challenges as global temperatures continue rising.
The research team, led by (Li et al., 2025), conducted multi-year field trials across different regions to identify QT12, a gene that controls how rice plants respond to heat stress. The study examined natural genetic variations in rice subspecies and tested their performance under real farming conditions rather than controlled laboratory environments.
The research revealed that QT12 works with a group of regulatory proteins called NF-Y transcription factors to form what scientists describe as a natural “gene on-off system.” Under normal temperatures, this system keeps QT12 activity low, maintaining good grain quality and yield. However, when temperatures rise, the protective mechanism breaks down, allowing QT12 to become overactive and damage grain development.
Discovery Doubles Rice Production Under Heat
The breakthrough centers on understanding how different rice varieties naturally evolved to handle temperature stress. Indica rice, traditionally grown in warmer climates, contains genetic variations that keep the QT12 gene switched off even during heat waves. This natural protection system maintains the balance of storage proteins and starch in developing rice grains, preserving both quality and quantity of the harvest.
“Low QT12 expression confers superior quality and increases elite rice yield up to 1.31–1.93 times under large-scale high-temperature trials,” the researchers reported in their study published in Cell journal.
The team tested this discovery across multiple farming regions, demonstrating that rice varieties with optimized QT12 expression maintained high yields and superior grain quality even when exposed to the elevated temperatures that typically reduce crop productivity. This represents a significant advancement over traditional breeding methods that often require choosing between high yields or good quality.
Heat Stress Disrupts Cellular Protein Systems
The research revealed the specific biological mechanism behind heat-induced crop damage. QT12 functions as part of a cellular transport system called Sec61, which moves newly made proteins into storage compartments within plant cells. When temperatures rise and QT12 becomes overactive, this transport system malfunctions, triggering a stress response called the unfolded protein response (UPR).
This cellular stress disrupts the normal balance between protein and starch storage in rice grains, leading to chalky, low-quality rice with reduced nutritional value. The disruption also decreases overall yield, creating the double problem of less food that is also lower quality.
Global Food Security Applications
Agricultural experts view this discovery as particularly significant for food security in Asia and Africa, where rice serves as a primary food source for billions of people. Rising global temperatures have already reduced major crop yields by 3.1-7.4% with just a 1°C temperature increase, according to the study.
“Global food security is not only closely related to yield but also to quality, which determines human nutrition, market value, and farmer income, especially in Asia and Africa, where high temperatures are more frequent and populations are heavily reliant on cereals,” the research team explained.
Breeding Strategy for Climate-Smart Agriculture
The scientists identified what they call “trait regulatory haplotypes” (TRHs) – specific combinations of genetic variations that can be used in breeding programs to develop heat-tolerant rice varieties. This approach differs from traditional crop improvement methods because it can simultaneously enhance both yield and quality under stress conditions.
The research provides practical tools for agricultural development, offering a scientifically-proven method to develop rice varieties specifically adapted to future climate scenarios. The highly conserved nature of this genetic system suggests it could potentially be applied to improve heat tolerance in other major food crops beyond rice.
The study analyzed natural genetic variations across rice subspecies through multi-year field trials conducted in multiple geographic regions, examining both cellular mechanisms and large-scale agricultural performance under controlled high-temperature conditions.
Key Takeaways
- QT12 gene system increases rice yields 31-93% under heat stress through natural genetic variations that maintain cellular protein balance.
- Heat stress disrupts protein transport systems in rice cells, reducing both grain quality and quantity in traditional varieties.
- Scientists developed breeding tools using trait regulatory haplotypes to create climate-adapted rice varieties for global food security.
Reference
Li, W., Yang, K., Hu, C., Abbas, W., Zhang, J., Xu, P., Cheng, B., Zhang, J., Yin, W., Shalmani, A., Qu, L., Lv, Q., Li, B., He, Y., Lai, X., Xiong, L., Zhang, Q., & Li, Y. (2025). A natural gene on-off system confers field thermotolerance for grain quality and yield in rice. Cell. https://doi.org/10.1016/j.cell.2025.04.011
