Unravelling the differential responses of critically endangered Onobrychis conferta populations to drought and salinity stress

Understanding stress responses of endangered plants is vital for their conservation under climate change. We examined the effects of iso-osmotic drought (PEG) and salinity (NaCl) on the growth and physiology of three populations of the critically endangered legume Onobrychis conferta subsp. conferta...

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Detalhes bibliográficos
Autores: Sakhraoui, A., Ltaeif, H. B., Castillo Segura, Jesús Manuel, Rouz, S.
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2025
País:España
Recursos:Universidad de Sevilla (US)
Repositório:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:dnet:idus________::8eb5f7dbed7db29edd9390d60273dae6
Acesso em linha:https://hdl.handle.net/11441/184009
https://doi.org/10.32615/ps.2025.034
Access Level:Acceso aberto
Palavra-chave:Chlorophyll
Fluorescence
Gas exchange
Iso-osmotic stress
NaCl
Sainfoin
Descrição
Resumo:Understanding stress responses of endangered plants is vital for their conservation under climate change. We examined the effects of iso-osmotic drought (PEG) and salinity (NaCl) on the growth and physiology of three populations of the critically endangered legume Onobrychis conferta subsp. conferta (OC1, OC2, OC3) endemic to North-Western Tunisia. Both stresses reduced photosynthesis, stomatal conductance, intercellular CO2and carboxylation efficiency, while increasing intrinsic water-use efficiency. PSII photoinhibition (Fv/Fmdecline) occurred after 6 d. Prolonged stress suppressed growth and water content, particularly under salinity, but enhanced root elongation and root-to-shoot ratios in OC1 and OC2. OC3, from dry grasslands, showed higher water retention, photosynthetic efficiency, and adaptive morphology than OC1 (Pinus forest) and OC2 (watercourse edge), highlighting ecotype-dependent tolerance. OC1 exhibited increased root allocation under salinity, exhibiting a salt-avoidance strategy. Identifying resilient ecotypes is crucial for conservation, restoration, and adaptation of O. conferta to increasing drought and salinity.