Coat Colour Grading of the Scots Pine Seeds Collected from Faraway Provenances Reveals a Different Germination Effect

Abstract

The physiological quality of pine seeds is characterized by laboratory and field germination. The present paper is intended for technologists of seed plants and specialists of forest nurseries. It offers a solution to improve the seeding characteristics of small seeds by their pre-sowing preparation. The success of reforestation activities directly depends on the quality of the seeds. The influence of seed sorting by seed size and seed coat colour has been theoretically substantiated and repeatedly tested in practice. However, the response of seeds in germination can vary depending on the year and place of seed collection. Scots pine (Pinus sylvestris L.) seeds were germinated under controlled conditions. Seedlings were obtained from seeds pre-sorted by seed coat colour into white, brown, and black groups, and further divided by size. The results of sorting by the colour of seed coat indicate a different effect of this pre-sowing treatment on the sowing qualities of seeds. Brown seed coat colour showed the highest percentage degree in the seedlots of all provenances. The seeds from the southern provenance with the brown seed coat colour shown the maximum germination. That said, the study raises new questions, indicating more comprehensive research in the future. Does the pattern of germination parameter distribution remain constant for seeds of other harvest years but of the same provenance? Does the variability of the germination factor the result of internal factors of the container location in the greenhouse? Is the genetic diversity of seedlings disturbed by sorting by size?