Effect of saline priming in Cucurbita ficifolia Bouché seeds on germination parameters and synthesis of proline

In northern Chile production and quality of cucurbits is affected by salinity water and soil. Cucurbita ficifolia is an option as salinity tolerant rootstock. The aim of this study was to determine the effect of saline priming in seeds of Cucurbita ficifolia on the parameters of germination and synthesis of proline. Seeds were primed with two salt solutions of 300 and 600 mM L^-1 of NaCl for 96 h at 20±1°C. Subsequently primed and non-primed seeds were put to germinate for 88 h in petri dishes in four solutions (DG): 0, 25, 50 and 75 mM L^-1 of NaCl. Per treatment were sown 100 seeds divided into ten repetitions. The parameters evaluated were: germination percentage and speed, length and speed of growth of the radicle, and germination rate priming effect (GIPr) and per dissolution of germination (GIDg) as biochemical parameter was determined proline synthesis at 88 h of germination. The results showed an advance and uniform germination of primed seeds. The highest GIPr was obtained with the priming of 300 mM L^-1 (+107%) referred to control; instead the GIDg, there were no significant differences obtained. In regard to Proline there was no interactive effect between priming and DG. The results obtained indicate that the seed of C. ficifolia priming with 300 mM L^-1 (28.65 mS cm^-1 = Ψs: -1.33 MPa) has tolerance to the salinity conditions evaluated, with a synthesis of 2.96 μmol Proline g^-1 fw.