News » 22.10.2026 - Enhancing cold tolerance in begonias

Begonia, with 2200 species, is one of the most popular bedding plants worldwide, yet most species are highly sensitive to cold temperatures (≤15 °C). Begonia grandis is the only species considered "hardy," capable of overwintering at low temperatures, offering a valuable opportunity to develop new cold-tolerant begonias.

Researchers aimed to characterize cold tolerance in a B. grandis collection of six accessions using a high-throughput phenotyping platform (HTPP) and traditional phenotyping methods. Five B. grandis accessions and one Begonia hybrid were selected from The Ohio State University Ornamental Plant Germplasm Center (OPGC). Mature plants were used in two experiments conducted under chilling conditions and freezing conditions. For the chilling experiment, plants were acclimated from 22 °C to 10 °C for 28 d, followed by 4 °C for 13 d. For the freezing experiment, plants were acclimated from 22 °C to 10 °C for 28 d, followed by 4 °C for 7 d and then were subsequently ramped down to –5 °C for a momentary freeze exposure. An HTPP TraitFinder (Phenospex) was used to assess phenotypic responses under cold stress. Morphological and spectral traits were affected significantly by chilling and freezing temperatures, with variation among accessions. Digital biomass loss predicted by the HTPP correlated closely with biomass loss measured using traditional measurements. Under chilling stress, the most cold-tolerant accession was OPGC 3143, whereas OPGC 2762 was the least tolerant. Under freezing conditions, OPGC 2758 showed the greatest tolerance; OPGC 2759, the lowest.

This is the first study to apply an HTPP to evaluate low-temperature responses in the Begonia genus. Identifying the most cold-tolerant accessions provides a foundation for future genetic mapping of cold-tolerance genes and supports the development of new Begonia germplasm with improved cold tolerance.

Mendez-Urbano, Freddy & Chapin, Laura & Jones, Michelle & Taylor, Leslie & Ma, Yu. (2026). Enhancing Cold Tolerance in Begonia: Germplasm Characterization of Begonia grandis Under Cold Stress. HortScience. 61. 2385-2395. 10.21273/hortsci19627-26.
 

Source: www.floraldaily.com

« Back