Cherry trees and supercooling: a natural defence against frost

20 Mar 2025
188

Studying supercooling in cherry trees

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 impact of extreme cold

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.

A research focus on cherry trees

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.

The critical moment: from snow to spring

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


Cherry Times - All rights reserved

What to read next

China: rising production and imports in 2025 according to a US report

Markets

03 Sep 2024

Cherry production in China is expected to rise by 6% in the 2024/25 marketing year, reaching 850,000 tons. The increase is attributed to the expansion of the cultivated area for cherries and higher fruit yields. Consumption is also expected to rise, thanks to improved stocks.

How to prevent cherry pitting on fruits?

Tech management

08 Jan 2025

The surface pitting damage is caused by mechanical damage before and after harvest. The defect only manifests itself after 7-10 days of cold storage, after packing and inspection of the fruit, and has substantial economic implications.

In evidenza

Sweet cherry cracking: the Romanian study linking fruit quality to resistance

Quality

18 Apr 2025

A Romanian study explores the link between sweet cherry cracking and fruit quality factors such as weight, firmness, and pH. Findings provide actionable insights for enhancing cultivar resistance and supporting cherry growers in challenging climates.

Lightweight agrivoltaics over cherry trees: a pioneering pilot plant in Germany

Covers

18 Apr 2025

A groundbreaking agrivoltaic pilot project in Germany installs lightweight solar panels over cherry orchards using existing weather protection systems—maximizing land use, preserving fruit yields and offering a replicable, sustainable model for smart farming across Europe.

Tag Popolari