Abstract:  In order to study the effects of preculture conditions on germination of sunflower broomrape seeds,different preculture conditions, including temperature, osmotic potential, preculture time, pH and gibberellin con⁃centration, were set to conduct one element experiments and orthogonal design experiments. The one element experi⁃ment results showed that the optimal preculture conditions were temperature at 25℃, preculture time at 7 days, os⁃motic potential at 0 MPa, pH 7.0, with concentration of gibberellins of 30 mg/mL . The orthogonal design experi⁃ment results showed that, the primary and secondary influence order of the elements which affect the germination of sunflower broomrape seeds was preculture temperature＞preculture time＞osmotic potential＞pH. The optimal pre⁃culture conditional combination included temperature at 25℃ , preculture time at 7 days, osmotic potential at-0.5 MPa, pH 7.0. The germination rate of sunflower broomrape seeds reached the highest of 75.85% at the optimal preculture conditional combinations.

Key words: sunflower broomrape, pre-culture conditions, germination rate