The Salt Sensitivity Induced by Disruption of Cell Wall-Associated Kinase 1 () Tomato Gene Is Linked to Altered Osmotic and Metabolic Homeostasis.

Tomato cell wall-associated kinase 1 () has only been studied in biotic stress response and hence its function in abiotic stress remains unknown. In a screening under salinity of an insertional mutant collection of tomato ( L.), a mutant exhibiting lower degree of leaf chlorosis than wild type (WT) together with reduced leaf Na accumulation was selected. Genetic analysis of the mutation revealed that a single T-DNA insertion in the gene was responsible of the mutant phenotype. null mutant reduced its shoot growth compared with WT, despite its improved Na homeostasis. disruption affected osmotic homeostasis, as leaf water content was lower in mutant than in WT under salt stress. In addition, altered the source-sink balance under salinity, by increasing sucrose content in roots. Finally, a significant fruit yield reduction was found in vs. WT under long-term salt stress, mainly due to lower fruit weight. Our results show that disruption of induces a higher sucrose transport from source leaf to sink root, negatively affecting fruit, the main sink at adult stage.