文摘
-Introduction In Cryptomeria japonica, heartwood properties are considered to be affected by specific extractives. It remains unclear whether traits of specific heartwood compounds are under genetic control. -Methods Two major heartwood norlignans, agatharesinol (A) and sequirin C (S), were determined quantitatively and qualitatively in 29 C. japonica plus-tree clones to evaluate their clonal variations and clonal repeatability. -Results The content of two norlignans and their composition (S)mol/((A)mol + (S)mol) varied significantly depending on the clone, suggesting that the biosynthesis of norlignan is genetically regulated in C. japonica. In particular, the clonal repeatability of sequirin C was higher than that of both agatharesinol and total norlignan content. In addition, the clonal repeatability of the norlignan molar ratio was quite high. These results suggested that genetic involvement is greater in the accumulation of sequirin C than agatharesinol. No significant correlation was found between agatharesinol and sequirin C content, or between the total norlignan content and the norlignan molar ratio, suggesting that the formation of agatharesinol and sequirin C in norlignan biosynthesis is independently controlled in C. japonica. -Conclusions It was suggested that the traits of the specific heartwood extractive norlignans were under genetic control in C. japonica.