Henery Martin L, Moran Gavin F, Wallis Ian R, Foley William J
School of Botany and Zoology, Australian National University, Canberra ACT 0200, Australia.
New Phytol. 2007;176(1):82-95. doi: 10.1111/j.1469-8137.2007.02159.x. Epub 2007 Aug 13.
Leaves of eucalypt species contain a variety of plant secondary metabolites, including terpenoids and formylated phloroglucinol compounds (FPCs). Both terpene and FPC concentrations are quantitative traits that can show large variation within a population and have been shown to be heritable. The molecular genetic basis of this variation is currently unknown. Progeny from a field trial of a three-generation mapping pedigree of Eucalyptus nitens were assayed for terpenes and FPCs. Quantitative trait loci (QTL) analyses were conducted using a map constructed from 296 markers to locate regions of the genome influencing foliar concentrations of these plant secondary compounds. A large number of significant QTL for 14 traits were located across nine linkage groups, with significant clustering of QTL on linkage groups 7, 8 and 9. As expected, QTL for biosynthetically related compounds commonly colocated, but QTL for unrelated monterpenes and FPCs also mapped closely together. Colocation of these QTL with mapped candidate genes from the various biosynthetic pathways, and subsequent use of these genes in association mapping, will assist in determining the causes of variation in plant secondary metabolites in eucalypts.
桉树种的叶子含有多种植物次生代谢产物，包括萜类化合物和甲酰化间苯三酚化合物（FPCs）。萜烯和FPC的浓度都是数量性状，在一个种群中可能表现出很大的差异，并且已被证明具有遗传性。这种变异的分子遗传基础目前尚不清楚。对来自桉树三代作图谱系田间试验的后代进行了萜类化合物和FPC的测定。使用由296个标记构建的图谱进行数量性状位点（QTL）分析，以定位影响这些植物次生化合物叶片浓度的基因组区域。在九个连锁群上定位了大量与14个性状相关的显著QTL，在连锁群7、8和9上QTL显著聚集。正如预期的那样，生物合成相关化合物的QTL通常共定位，但不相关的单萜和FPC的QTL也紧密连锁在一起。这些QTL与来自各种生物合成途径的已定位候选基因的共定位，以及随后在关联作图中使用这些基因，将有助于确定桉树叶中植物次生代谢产物变异的原因。
