Occurrence of monoterpenes in Pinus radiata and utilization of labeled CO₂ and mevalonic acid

β-Pinene, α-pinene and limonene are the most abundant monoterpenes of resins, needles, shoot tips and seedlings from Pinus radiata grown in Chile. The limonene contents of tissues is much higher than that of resins. More ¹⁴CO₂ is incorporated into β-piene than into α-pinene in a young tree. In isolated needles, the β-isomer attains higher specific radioactivity than the α-isomer. The properties of mevalonic kinase from P. radiata seedlings are similar to those reported for other organisms.