The effect of salt stress on Arabidopsis thaliana and Phelipanche ramosa interaction

Salinity and Orobanche or Phelipanche spp. infection are important crop stress factors in agricultural areas. In this study, we investigated the effect of salt stress on Phelipanche ramosa seed germination and its attachment onto Arabidopsis thaliana roots. We also evaluated the effect of both stresses on the expression of genes regulated by abiotic and biotic stresses. According to our results, high concentration of NaCl delayed P.ramosa seed germination in the presence of a strigolactone analogue (GR24). A similar pattern was observed in the presence of A.thaliana plants. Furthermore, we found that salt-treated A.thaliana seedlings were more sensitive to P.ramosa attachment compared with the untreated plants, indicating that there was a positive correlation between salt sensitivity and the ability of P.ramosa to infect A.thaliana plants. At the molecular level, a synergystic effect of both salt and P.ramosa stresses was observed on the cold-regulated (COR) gene expression profile of treated A.thaliana seedlings. Our data clarify the interaction between parasitic plants and their hosts under abiotic stress conditions.