Scientists at the University of British Columbia Okanagan are studying how sweet cherry trees protect their flower buds from winter frost, using a natural mechanism called supercooling.
Dr. Elizabeth Houghton, a graduate of the Irving K. Barber Faculty of Science, published a study in the journal Plant Biology analyzing this phenomenon. Supercooling allows the liquids within plant cells to remain in a liquid state even at subzero temperatures, preventing ice formation. However, this delicate balance can break if impurities or ice crystals intervene, leading to sudden freezing.
This process is vital for flower buds, which must survive the cold months to ensure the production of fruits in the following season.
The importance of better understanding this mechanism became clear after an exceptional cold wave hit Okanagan in January 2024, with temperatures dropping as low as -27°C (-16.6°F). The damage to fruit trees was devastating, with estimates indicating a loss of 90% of the anticipated summer crop.
Many tree species have strategies to withstand cold, but supercooling in stone fruits, like cherries, remains poorly understood.
Figure 1: Ice accommodation in overwintering sweet cherry flower buds exposed to in-field sub-zero temperatures. Photographs taken under a dissecting microscope on 24 February 2023 of a sweet cherry flower bud that was: (a) held at in-field freezing temperatures after experiencing a natural cold snap along with a digital diagram of the same flower bud to highlight regions of ice accommodation, then (b) thawed to room temperature. Credit: Plant Biology (2024). DOI: 10.1111/plb.13697
“The ability of sweet cherry trees to withstand winter frost through supercooling is fascinating. In this state, cellular liquids do not freeze despite subzero temperatures,” explains Dr. Houghton. “But we still don’t know exactly how this happens in certain plant structures. We want to dive deeper to understand how flower buds survive such extreme conditions.”
Unlike previous research, which mainly focused on peaches, this study shifts attention to cherries. Their buds contain more primordia — cellular structures that will develop into flowers and later into fruits — compared to peach buds, which contain only one.
Dr. Houghton examined various aspects of the phenomenon: from ice formation inside the buds to the freezing of outer layers, and the changes occurring within the buds as temperatures begin to rise with the arrival of spring.
One of the most critical aspects is the transition from winter to spring. As the buds grow, they gradually lose the ability to stay supercooled, becoming vulnerable to sudden cold snaps.
“Cherry buds have an extraordinary ability to protect themselves from frost in winter, but this defense weakens with spring growth,” the researcher explains. “We want to better understand how these buds endure such harsh winter temperatures. And with the uncertainty surrounding climate change and the possibility of more frequent and intense cold waves, it’s crucial to learn from these plants to develop strategies that safeguard future crops.”
Source: Phys.org
10 Apr 2024
Burro units are fully electrified, allowing to greatly enhance sustainable footprint in operations, with estimated reduction in carbon emissions of up to 80,000kg’s of C02e annually, and 70% reduction in running costs per 40-hectares block of cherries.
02 Jul 2024
Roxane Flores, Director of Human Capital Development and Regulatory Affairs at AFIPA, shares her visit with Cristián Osorio, a cherry grower from Coltauco, and together they discuss the main challenges that Chilean farmers face in bringing their cherries to international markets.
03 Jul 2026
Research in Moldova on sweet cherry shows Thin spindle improves yield, fruit quality and canopy management in high-density orchards on Gisela 6, while Improved thin spindle boosts large premium fruit, uniformity and commercial value for modern intensive cherry production.
03 Jul 2026
Chilean cherries 2025/26 face a more saturated China market, flat FOB prices and rising pressure on quality, timing and destinations. Diversification toward the United States and other markets is becoming crucial to protect Chile’s profitability and fruit exports now.
