Molecular control to salt tolerance mechanisms of woody plants: recent achievements and perspectives

Abstract

Key message Woody plants have salt-tolerant mechanisms similar to those developed by non-woody plants. Among others, compartmentalization of ions, production of compatible solutes, synthesis of specific proteins and metabolites, and induction of transcriptional factors are the most relevant. Woody plant-associated microbial interactions as well as naturally stress-adapted trees are resources that deserve to be deepened to fully understand the tolerance mechanisms. Context The high variability of salinity responses found in woody plants implies a high potentiality for germplasm selection and breeding. Salt tolerance mechanisms of plants are regulated by numerous genes, which control ion homeostasis, production of compatible solutes and specific proteins, and activation or repression of specific transcription factors. Despite the fact that numerous studies have been done on herbaceous model plants, knowledge about salt tolerance mechanisms in woody plants is still scarce. Aims The present review critically evaluates molecular control of salt tolerance mechanisms of woody plants, focusing on the regulation and compartmentalization of ions, production of compatible solutes, activation of transcription factors, and differential expression of stress response-related proteins, including omics-based approaches and the role of plant-microbial interactions. The potential identification of genes from naturally stress-adapted woody plants and the integration of the massive omics data are also discussed. Conclusion In woody plants, salt tolerance mechanisms seem not to diverge to those identified in non-woody plants. More comparative studies between woody and non-woody salt tolerance plants will be relevant to identify potential molecular mechanisms specifically developed for wood plants. In this sense, the activation of metabolic pathways and molecular networks by novel genetic engineering techniques is key to establish strategies to improve the salt tolerance in woody plant species and to contribute to more sustainable agricultural and forestry systems.

Salt stress and organic fertilization on the growth and biochemical metabolism of Hylocereus costaricensis (red pitaya) seedlings

“…The ability to store water and solutes in their tissues guarantees the growth and development of these plants under salt stress conditions. Salinity tolerant plants can selectively accumulate ions and thus maintain the osmotic adjustment, ensuring water absorption (Llanes et al, 2021). When evaluating the salinity tolerance of cactus, Schuch and Kelly (2008) observed that saguaro cactus and golden barrel cactus were tolerant to all salinity levels without altering the total dry mass content; these cactus species relied on osmotic adjustment based on increased osmotic potential and higher concentrations of sodium and chloride in the stem tissue.…”

Meta-analysis of the impact of future climate change on the area of woody plant habitats in China

“…Woody plants with longer life cycles and larger body sizes are more tolerant to harsh conditions such as habitat fragmentation or climate change ( Harper, 1977 ; Petit and Hampe, 2006 ; Sork et al., 2013 ; Olson et al., 2016 ; Llanes et al., 2021 ). Because shrubs have a shorter life cycle and can settle in new suitable areas more quickly than trees, the overall suitable area for shrubs (+8.52%) increased more, and the highly suitable area for shrubs (–0.22%) decreased less than that of trees (–42.81%) under future climate change projections ( Hiernaux et al., 2009 ).…”

Identification of Early Salt-Stress-Responsive Proteins in In Vitro Prunus Cultured Excised Roots

“…In this study, an in vitro approach was used to highlight whether cultured excised roots could detect similar responses in proteomics profiles compared to using roots from plants grown by traditional methods. Even though there are no proteomics studies on the responses of woody plants to salt stress, according to [19][20][21], woody plants have salttolerant mechanisms similar to those developed by non-woody plants. Several differential proteomics studies on the responses of herbaceous plant roots to salt stress have been published in recent decades [18,[22][23][24][25].…”