Laitinen Marja-Leena, Julkunen-Tiitto Riitta, Tahvanainen Jorma, Heinonen Jaakko, Rousi Matti
Department of Pharmaceutical Chemistry, University of Kuopio, P.O. Box 1627, 70211 Kuopio, Finland.
J Chem Ecol. 2005 Apr;31(4):697-717. doi: 10.1007/s10886-005-3539-7.
Plant secondary chemistry is determined by both genetic and environmental factors, and large intraspecific variation in secondary chemistry has frequently been reported. The heritability of specific tree secondary metabolites is, however, mostly unknown. We tested the effect of plant genotype, environment, and ontogeny on the variation in shoot secondary chemistry of juvenile and mature European white birches (Betula pendula). Phenolic compounds and triterpenoids were analyzed in 30 naturally regenerated 20-year-old parental trees and micropropagated plantlets that originated from 14 of those same parental trees, planted at four growing sites. Most of the variation for phenolic compounds was explained by differences between parental trees, whereas triterpenoids had a high variation both between parental trees and within the canopy of individual tree. The effect of ontogeny was strong for some individual compounds. In mature trees, the amount of triterpenoids was less than 1 mg/g (DW), whereas the concentration in juvenile plantlets was up to 64 mg/g (DW). Clonal plantlets and parental trees were generally quite similar in their phenolic contents, but there were significant differences for all analyzed compounds among clones. Environment had no significant effect on the accumulation of some compounds, whereas for others, a significant environmental effect and/or significant genotype by environment interaction was found. These results suggest that birch shoot secondary chemistry is under strong genetic control and that the environmental effects depend on the studied chemical trait.
植物次生化学由遗传和环境因素共同决定，种内次生化学的巨大变异也屡有报道。然而，特定树木次生代谢产物的遗传力大多未知。我们测试了植物基因型、环境和个体发育对幼年和成熟欧洲白桦（Betula pendula）嫩枝次生化学变异的影响。对30株自然再生的20年生母树以及源自其中14株相同母树的微繁殖幼苗进行了酚类化合物和三萜类化合物分析，这些植株种植在四个生长地点。酚类化合物的大部分变异可由母树之间的差异解释，而三萜类化合物在母树之间以及单株树冠内都有很大变异。个体发育对某些个别化合物的影响很强。在成熟树木中，三萜类化合物的含量低于1毫克/克（干重），而在幼年幼苗中浓度高达64毫克/克（干重）。克隆幼苗和母树的酚类含量通常相当相似，但不同克隆之间所有分析化合物都存在显著差异。环境对某些化合物的积累没有显著影响，而对其他化合物则发现了显著的环境影响和/或显著的基因型与环境的相互作用。这些结果表明，白桦嫩枝次生化学受到强大的遗传控制，且环境影响取决于所研究的化学性状。
