Variation in Seed Traits, Germination Performance, and Seedling Morphology of Cotinus coggygria (Scop.) in Relation to Provenance and Seed Size

Cotinus coggygria (Scop) is a medicinally valuable species naturally distributed in the Artvin region of Turkiye. However, information on its seed traits, germination behavior, and seedling morphology in relation to seed size and provenance remains limited. This study aimed to evaluate the effects of seed size and provenance on the seed characteristics, germination, and seedling morphological traits of C. coggygria. Seeds were collected from four provenances (Seyitler, Tepekoy, Eskikale, and Tortum) and classified into large and small size groups using a 2 mm sieve. The seed traits of length, diameter, thickness, sphericity, volume, and thousand-seed weight were considered. To break seed dormancy, the seeds were subjected to sulfuric acid scarification and cold stratification treatments. Germination trials were conducted under nursery conditions using 45-cell trays in a randomized block design with four replicates. The mean germination time was significantly affected by provenance, whereas seed size and pretreatment combinations had no significant effects. Seed size did not significantly influence seedling morphology, whereas provenance caused significant differences. Seedlings originating from Eskikale exhibited greater height and root collar diameter, with root mass fractions ranging from 80.25% to 82.78%. These results indicate that provenance is a key factor influencing germination and seedling morphology rather than seed size.