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Karlova, R.

Publications and source records attributed to Karlova, R..

2 recordsLinked to original sources

Potato cultivars use different root physiological and molecular mechanisms to acclimate to salt stress

O_LISoil salinity induces osmotic stress and ion toxicity in plants, detrimentally affecting their growth and development. Potato (Solanum tuberosum) faces yield reductions due to salt stress. The mechanisms of salt stress resilience, especially in adventitious roots, remain unknown. C_LIO_LIWe investigated the resilience of three potato cultivars - Desiree, Innovator, and Mozart - by studying their physiological and transcriptomic responses to salt stress. C_LIO_LIOur findings reveal that under salt stress, the growth of stolons and stolon node roots is similarly reduced unlike tubers, even though they are physically connected. Surprisingly, tubers accumulate Cl- but not Na+ under salt stress, suggesting an active Na+ exclusion mechanism. Innovator showed the lowest suberin and lignin deposition before salt stress and higher K+ leakage, leading to a stronger initial stress response with high ABA content and a distinct transcriptomic pattern. Nevertheless, Innovator was the most resilient, displaying lower growth, salt-tolerance index and tuber yield reduction. Transcriptomic analysis revealed several K+/Na+ channel genes which might regulate ions homeostasis during salt stress, in particular in Innovator. C_LIO_LIAltogether, we conclude that acclimation ability, rather than initial protection of roots against salt, prevails in long term salt-stress resilience of potato. C_LI

plant biology↗

Characterization of a major QTL for sodium accumulation in tomato shoot

Soil salinity is a serious concern for tomato culture, affecting both yield and quality parameters. Although some genes involved in tomato salt tolerance have been identified, their genetic diversity has been rarely studied. In the present study, we assessed salt tolerance-related traits at juvenile and adult stages in a large core collection and identified salt tolerance QTLs by genome-wide association study (GWAS). The results suggested that a major QTL is involved in leaf sodium accumulation at both physiological stages. We were able to identify the underlying candidate gene, a well-known sodium transporter, called SlHKT1.2. We showed that an eQTL for the expression of this gene colocalized with the sodium content QTL. A polymorphism putatively responsible for its variation was identified in the gene promoter. Finally, to extend the applicability of these results, we carried out the same analysis on a test-cross panel composed of the core collection crossed with a distant line. The results indicated that the identified QTL retained its functional impact even in a hybrid genetic context: this paves the way for its use in breeding programs aimed at improving salinity tolerance in tomato cultivars. Summary statementThe genetic diversity of sodium accumulation in tomato shoot under salt stress is associated with an expression QTL of SlHKT1.2. This gene, already identified as involved in tomato salinity tolerance, has been differentially selected during domestication and is of interest for the development of salinity-tolerant varieties.

plant biology↗