Seasonal variation of the terpenes of the leaves, buds, and twigs of blue spruce (Picea pungens)

Abstract

The variation in the relative amounts of the terpenes of the mature and young leaves, buds, and twigs of blue spruce was investigated during a full year. As with the spruces that were investigated previously, large changes were recorded only in the buds and in the young leaves after bud burst. The variations that were recorded in the latter for santene, tricyclene, camphene, camphor, bornyl acetate, and limonene were similar to those that were found in white spruce, but those of car-β-ene, α-pinene, and β-pinene differed. Several quantitative differences in the oil of the winter buds were also recorded. The variation of β-pinene correlated negatively with that of sabinene, γ-terpinene, and terpinolene. A transient diterpene alcohol of the geranylgeraniol type was found in the buds and young twigs during spring. The seasonal variation of the terpenes of the twig oil was smaller than the twig-to-twig variation within a tree. The implications for chemosystematic studies are discussed.