Uncovering salt tolerance mechanisms in pepper plants: a physiological and transcriptomic approach
Author
López-Serrano, Lidia; Calatayud, Ángeles; López-Galarza, Salvador; Serrano, Ramón; Bueso, EduardoDate
2021Cita bibliográfica
López-Serrano, L., Calatayud, Á., López-Galarza, S., Serrano, R., & Bueso, E. (2021). Uncovering salt tolerance mechanisms in pepper plants: a physiological and transcriptomic approach. BMC plant biology, 21(1), 1-17.Abstract
Background: Pepper is one of the most cultivated crops worldwide, but is sensitive to salinity. This sensitivity is
dependent on varieties and our knowledge about how they can face such stress is limited, mainly according to a
molecular point of view. This is the main reason why we decided to develop this transcriptomic analysis. Tolerant
and sensitive accessions, respectively called A25 and A6, were grown for 14 days under control conditions and
irrigated with 70 mM of NaCl. Biomass, different physiological parameters and differentially expressed genes were
analysed to give response to differential salinity mechanisms between both accessions.
Results: The genetic changes found between the accessions under both control and stress conditions could
explain the physiological behaviour in A25 by the decrease of osmotic potential that could be due mainly to an
increase in potassium and proline accumulation, improved growth (e.g. expansins), more efficient starch
accumulation (e.g. BAM1), ion homeostasis (e.g. CBL9, HAI3, BASS1), photosynthetic protection (e.g. FIB1A, TIL, JAR1)
and antioxidant activity (e.g. PSDS3, SnRK2.10). In addition, misregulation of ABA signalling (e.g. HAB1, ERD4, HAI3)
and other stress signalling genes (e.g. JAR1) would appear crucial to explain the different sensitivity to NaCl in both
accessions.
Conclusions: After analysing the physiological behaviour and transcriptomic results, we have concluded that A25
accession utilizes different strategies to cope better salt stress, being ABA-signalling a pivotal point of regulation.
However, other strategies, such as the decrease in osmotic potential to preserve water status in leaves seem to be
important to explain the defence response to salinity in pepper A25 plants.