Hydropriming as inducer of salinity tolerance in sunflower seeds

Sunflower is a species with multiple potentialities and its yield can be affected by the presence of soluble salts in the soil, which is common in arid, semi-arid and irrigated regions. The objective of this study was to evaluate the effect of hydropriming as inducer of salinity tolerance in seeds and seedlings of sunflower, hybrid MG305CP. The germination tests were set with four replicates of 50 seeds per treatment, maintained in germinator at 30 degrees C for ten days. To simulate salinity, sodium chloride diluted in distilled water was used at electrical conductivities of 0 (control), 4, 8, 12 and 16 dS m(-1). On the tenth day, the number of normal seedlings was counted and the length and dry matter of shoots and roots were determined. Seedling fresh matter was used to determine the contents of total chlorophyll, total soluble sugars and proline. The experimental design was completely randomized, in a 2 x 5 factorial scheme (with and without hydropriming and five levels of salinity). Hydroprimed sunflower seeds showed greater vigor expression, with higher number of normal seedlings and faster germination.