Maturity of Scots Pine Cones

Abstract

Cone and seed maturity of Scots pine (Pinus sylvestris L.) were evaluated for three seed years and several plantations in prairie Canada. Both specific gravity and moisture content provided reliable measures of cone maturity and were directly related to viability of the seed produced. Individual trees were found to differ as to cone and seed maturity for successive harvests in three years. Cones were mature when specific gravity decreased to 1.02 or a moisture content to 38% and produced seed with a high germination capacity even after four years of storage (81 to 95%). Distilled water is recommended for field testing of cone maturity for individual trees. Number of seeds per cone and seed weight were more directly related to cone size than to cone maturity. Neither color of cones nor color of seeds proved reliable measures of maturity.La m'aturite des cbnes et des semences de Pin sylvestre (Pinus sylvestris L.) a Btb calculee pour trois annees de semences dans plusieurs plantations des Prairies de I'Ouest canadien. La densite et le degre d'humidite ont tous deux permis de mesurer avec exactitude la maturite des c8nes et etaient directement rattaches a la viabilite des semences engendrees. On a trouve que les arbres differaient entre eux tant qu'a la maturite des cbnes et des semences pour les trois annees successives de recolte. La maturite des cbnes arrivait lorsque la densite baissait 5 1.02 ou le degie d'humidite a 38% et les semences produites avaient une capacite germinative elevee m&me aprhs quatre annees d'entreposage (81 h 95%). 11 est preferable d'employer de I'eau distill6 pour les tests sur le terrain pour la maturitb des cBnes d'arbres individuels. Le nombre de semences par cane et leur poids 6taient directement lies plutBt a la grosseur des cbnes qu'a leur maturit6. La couleur des cbnes pas plus que la couleur des semences n'a servi a mesurer exactement leur maturite.

Performance of Scots Pine Seedlings from Seeds Graded by Colour

“…Pinus sylvestris L. is a species known for a large natural variation in seed color, ranging from pale yellow to black [44]. Scots pine seed colour varies from tree to tree and becomes darker for each subsequent harvest date [45]. The same study shows that seed colour is not a reliable measure of seed maturity.…”

The Root Collar Diameter Growth Reveals a Strong Relationship with the Height Growth of Juvenile Scots Pine Trees from Seeds Differentiated by Spectrometric Feature

“…The Scots pine seed coat colour is under genetic control, and it can be used as a phenotypic marker [9][10][11][12][13][14]. There is a more than century-old interest of scientists [15][16][17][18] to study the seeds of Scots pine with different spectrometric properties [19,20] and, also, to study the growth of juvenile trees obtained from these seeds [21]. As for the size of the seeds, a direct correlation between the Scots pine seed size and seedling growth intensity is not always observed, since both empty large seeds and fossilized seeds are often found in seed lots.…”