Variables influencing cold tests of cherry blossom buds

28 Aug 2024
1718

Temperature is one of the main environmental factors limiting plant growth, development and yield. One of the main abiotic stress factors that limit plant distribution, crop production and influence the suitability of locations for orchard planting is low temperature conditions.

Frosts can cause considerable economic losses and, therefore, limit the presence of orchards in areas subject to these phenomena. Differential Thermal Analysis (DTA) is a method often used to assess the cold resistance of plant organs to survive cold temperatures.

For example, flowers are mounted on thermoelectric modules and subjected to cooling temperatures to perform DTA. The water inside the biological tissue is supercooled and solidifies, releasing heat that is detected as low temperature exotherm (LTE). This is assumed to be equivalent to the temperature at which embryos suffer lethal damage.

The only critical aspect of this method is that the analyses must be carried out in the laboratory, and the timing and transport protocols can influence the values obtained. A more complete understanding of the comparison between lethal temperature measurements obtained through controlled freezing experiments with currently available instruments and those obtained with DTA is therefore needed.

The objectives of the study by the University of British Columbia and the Research and Development Centre in Summerland (Canada) were:

  1. to evaluate the impact of temperature, humidity and pre-test storage duration on the cold resistance of sweet cherry blossom buds measured over a period of time between 0 and 25 hours;
  2. to evaluate the impact of differences in DTA cooling rates on the cold resistance of measured cherry blossom buds;
  3. investigate the impact of various bud removal methods on the cold resistance of measured cherry blossom buds;
  4. compare cold resistance measurements obtained by DTA and controlled freezing tests

As evidenced by the production of low-temperature exotherms at warmer temperatures, researchers found that buds stored at warmer temperatures (12.5 °C and room temperature) for 2-6 h prior to differential thermal analysis or transported to the laboratory in a humid environment underwent biologically relevant alterations in their apparent cold sensitivity.

Through numerous tests, the researchers realised that the speed at which the temperature was lowered to achieve the low temperature exotherms also significantly influenced the results. It was seen that higher values corresponded to faster cooling. In general, the obtained low-temperature exotherms were similar between the buds, although the amount of plant material remaining attached to the base of the bud varied.

The results of this study indicate that measures of cold resilience obtained from DTA and controlled freezing experiments are generally comparable. The results of this study are relevant for researchers interested in performing cold hardiness measurements in sweet cherry. They emphasise the importance of maintaining consistency in DTA pre-test conditions and bud preparation in order to obtain reliable and comparable results between studies.

Source: Elizabeth Houghton, Kirsten Hannam, Denise Neilsen, and Louise M. Nelson. 2024. Factors that influence measurements of sweet cherry (Prunus avium) flower bud cold hardiness obtained using differential thermal analysis. Canadian Journal of Plant Science. 104(3): 204-216. https://doi.org/10.1139/cjps-2023-0087.
Image: Canadian Science Publishing

Melissa Venturi
University of Bologna (IT)


Cherry Times - All rights reserved

What to read next

Chilean cherries and Chinese New Year: quality and strategy to avoid another flop

Markets

22 Dec 2025

Chilean cherries are preparing for Chinese New Year 2026 by focusing on quality and planning. After delays and losses last season, the industry is making a comeback with large, sweet, firm cherries with vibrant color, aiming to regain trust in the Asian market.

A.N.A. Chile® presents the Sweet series as an alternative to early varieties in Chile

Varieties

10 Jul 2024

Lorena Pinto pointed out that several trials are being conducted in Chile with Sweet Saretta and Sweet Stephany, 'and the calibre we have seen is above 30 and even 32. Moreover, they are self-fertile, so we have solved the pollination problem'.

In evidenza

Tart cherry: a new ally against inflammation and metabolic disorders

Health

23 Jan 2026

Two clinical studies confirm that daily intake of concentrated tart cherry extracts significantly reduces inflammatory markers such as CRP and blood urate levels, opening new perspectives for the functional role of tart cherry in supporting long-term metabolic health.

Controlled atmosphere to extend “Regina” cherries shelf life: effects on internal browning and quality

Post-harvest​

23 Jan 2026

A study from Chile proves that controlled atmosphere with 10-15% CO2 and 10% O2 extends Regina cherries' shelf life up to 40 days while preserving quality and flavor—an effective solution to improve logistics for long-distance exports, especially to Asia.

Tag Popolari