Distinct physiological and metabolic reprogramming by highbush blueberry (Vaccinium corymbosum) cultivars revealed during long-term UV-B radiation

• Published in: Physiologia Plantarum
• Main Authors: Luengo Escobar, Ana, Alberdi, Miren, Acevedo, Patricio, Machado, Mariana, Nunes Nesi, Adriano, Inostroza Blancheteau, Claudio, Reyes Daiz, Marjorie
• Format: Article in Journal/Newspaper
• Language: English
• Published: WILEY 2021
• Subjects: Antarc*; Antarctica
• Online Access: http://repositoriodigital.uct.cl/handle/10925/3750; https://doi.org/10.1111/ppl.12536

Despite the Montreal protocol and the eventual recovery of the ozone layer over Antarctica, there are still concerns about increased levels of ultraviolet-B (UV-B) radiation in the Southern Hemisphere. UV-B induces physiological, biochemical and morphological stress responses in plants, which are species-specific and different even for closely related cultivars. In woody plant species, understanding of long-term mechanisms to cope with UV-B-induced stress is limited. Therefore, a greenhouse UV-B daily course simulation was performed for 21 days with two blueberry cultivars (Legacy and Bluegold) under UV-B-BE irradiance doses of 0, 0.07 and 0.19Wm(-2). Morphological changes, photosynthetic performance, antioxidants, lipid peroxidation and metabolic features were evaluated. We found that both cultivars behaved differently under UV-B exposure, with Legacy being a UV-B-resistant cultivar. Interestingly, Legacy used a combined strategy: initially, in the first week of exposure its photoprotective compounds increased, coping with the intake of UV-B radiation (avoidance strategy), and then, increasing its antioxidant capacity. These strategies proved to be UV-B radiation dose dependent. The avoidance strategy is triggered early under high UV-B radiation in Legacy. Moreover, the rapid metabolic reprogramming capacity of this cultivar, in contrast to Bluegold, seems to be the most relevant contribution to its UV-B stress-coping strategy.