2017 ASHS Annual Conference

The seeds of Rubus offer a specific germination challenge because of their deep double dormancy caused by a stony endocarp and growth inhibitors inside the seed. Seed germination may be poor or slow, making it difficult for scientists to use when breeding improved cultivars. Seeds were collected from three cultivars in two of the Rubus subgenera studied. The experiment was set up as a CRD complete factorial, with four replications and 10 seeds per experimental unit. Three different extraction methods (manual extraction with a blender, fermentation of the fruit, and freezing of the fruit) were followed by scarification with sulfuric acid (98%) or no scarification. Seeds were then treated with a combination of Gibberellic acid (GA₃ 200 ppm) plus potassium nitrate (.2%), and stratified for 9 weeks at 4 ^oC and 16 hour light. Scarification was shown to greatly improve germination, as well as manual extraction. There were no differences observed between seeds treated with the GA₃ plus KNO₃.