Seed Dormancy and Germination Characteristics of Vaccinium oldhamii Miq. (Ericaceae)

Vaccinium oldhamii Miq. is an edible berry; however, little is known about its seed dormancy-break and germination. Therefore, the aim of this study was to elucidate the seed-dormancy break and germination characteristics of V. oldhamii. The results showed that the length and width of the seeds of V. oldhamii were 2.4588 ± 0.0273 mm and 1.7028 ± 0.0248 mm, respectively, the filled percentage was 49.0 ± 3.0%, and the 1000-seed weight was 0.9453 g. Additionally, water imbibition test showed that the seed weight of V. oldhamii increased by more than 70% after 24 h, indicating the absence of physical dormancy. Embryo length measured at dispersal and just before germination did not differ significantly. There was no significant difference in E:S (Embryo:Seed) ratio in length at the time of seed dispersal (0.6780 ± 0.0258) and before germination (0.7370 ± 0.0469), indicating the absence of morphological dominance. Temperature treatments showed that the germination of the seed was 0, 6.0, 6.0, 20.0, and 0% under 15, 20, 25, 25/15, and 15/6 °C, respectively. However, treatment with 250 ppm of GA3 increased the germination of the seeds to 22.0, 36.0, 32.0, 40.0, and 1.0%, respectively. Additionally, treatment with 500 ppm of GA3 increased the germination to 34.6, 40.0, 40.0, 46.0 %, respectively. These results indicated that the seeds of V. oldhamii exhibited Nondeep physiological dormancy (Nondeep PD). Overall, the findings of this study showed that treatment with 500 ppm of GA3 at 25/15 °C can effectively break the dormancy of V. oldhamii seeds, which could facilitate further research on the species.