BACKGROUND: Ultraviolet-B (UV-B) radiation can affect several aspects ranging from plant growth to metabolic regulation. Maca is a Brassicaceae crop native to the Andes growing in above 3500 m of altitude. Although maca has been the focus mainly due to its nutraceutical properties, it remains unknown how maca plants tolerate to harsh environments, such as strong UV-B. Here, we present the first study that reports the physiological responses of maca plants to counteract and recover to repeated acute UV-B irradiation. RESULTS: In detail, plants were daily exposed to acute UV-B irradiation followed by a recovery period under controlled conditions. The results showed that repeated acute UV-B exposures reduced biomass and photosynthetic parameters, with gradual senescence induction in exposed leaves, reduction of young leaves expansion and root growth inhibition. Negative correlation between increased UV-B and recovery was observed, with marked production of new biomass in plants treated one week or more. CONCLUSIONS: A differential UV-B response was observed: stress response was mainly controlled by a coordinated source-sink carbon allocation, while acclimation process may require UV-B-specific systemic defense response reflected on the phenotypic plasticity of maca plants. Moreover, these differential UV-B responses were also suggested by multifactorial analysis based on biometric and physiological data.

• MeSH
• chlorofyl a chemie   MeSH
• fluorescence MeSH
• fotosystém II (proteinový komplex) metabolismus   MeSH
• Lepidium fyziologie   účinky záření   MeSH
• listy rostlin fyziologie   účinky záření   MeSH
• metabolismus sacharidů účinky záření   MeSH
• škrob účinky záření   MeSH
• ultrafialové záření MeSH
• Publikační typ
• časopisecké články MeSH