BACKGROUND Chimeras synthesized artificially by grafting are crucial to the breeding of perennial woody plants. 'Hongrou Huyou' (Citrus changshan-huyou + Citrus unshiu) is a new graft chimera originating from the junction where a Citrus changshan-huyou ("C") scion was top-grafted onto a stock Satsuma mandarin 'Owari' (C. unshiu, "O"). The chimera was named OCC because the cell layer constitutions were O for Layer 1(L1) and C for L2 and L3. In this study, profiles of primary metabolites, volatiles and carotenoids derived from different tissues in OCC and the two donors were investigated, with the aim of determining the relationship between the layer donors and metabolites. RESULTS The comparison of the metabolite profiles showed that the amount and composition of metabolites were different between the peels and the juice sacs, as well as between OCC and each of the two donors. The absence or presence of specific metabolites (such as the carotenoids violaxanthin and β-cryptoxanthin, the volatile hydrocarbon germacrene D, and the primary metabolites citric acid and sorbose) in each tissue was identified in the three phenotypes. According to principal component analysis (PCA), overall, the metabolites in the peel of the chimera were derived from donor C, whereas those in the juice sac of the chimera came from donor O. CONCLUSION The profiles of primary metabolites, volatiles and carotenoids derived from the peels and juice sacs of OCC and the two donors were systematically compared. The content and composition of metabolites were different between the tissues and between OCC and the each of the two donors. A clear donor dominant pattern of metabolite inheritance was observed in the different tissues of OCC and was basically consistent with the layer origin; the peel of the chimera was derived from C, and the juice sacs of the chimera came from O. These profiles provide potential chemical markers for genotype differentiation, citrus breeding assessment, and donor selection during artificial chimera synthesis.

中文翻译：

---

嫁接嵌合体“红柔虎油”（Citrus changshan-huyou + Citrus unshiu）及其两种供体植物的代谢物谱比较。

背景技术通过嫁接人工合成的嵌合体对于多年生木本植物的育种至关重要。“红肉胡柚”（柑橘长山胡柚+柑桔）是一种新的嫁接嵌合体，起源于将柑橘长山胡柚（“ C”）接穗顶部嫁接到萨摩普通话“ Owari”（柑桔）上的交界处。 ，“ O”）。嵌合体被命名为OCC，因为第1层（L1）的细胞层结构为O，L2和L3的细胞层结构为C。在这项研究中，调查了OCC和两个供体中来自不同组织的主要代谢物，挥发物和类胡萝卜素的概况，目的是确定层供体与代谢物之间的关系。结果代谢物谱的比较表明，果皮和汁囊之间以及OCC与两个供体之间的代谢物含量和组成均不同。在这三种表型中，确定了每个组织中是否存在特定的代谢产物（例如类胡萝卜素紫黄质和β-隐黄质，挥发性烃胚芽烯D和主要代谢产物柠檬酸和山梨糖）。根据主成分分析（PCA），总的来说，嵌合体果皮中的代谢物来自供体C，而嵌合体果汁囊中的代谢物则来自供体O。系统地比较了OCC的果皮和汁囊中的两个供体。在组织之间，OCC与两个供体中的每一个之间，代谢物的含量和组成均不同。在OCC的不同组织中观察到清晰的供体代谢产物遗传的显性模式，并且与层起源基本一致。嵌合体的果皮来自C，嵌合体的汁囊来自O。这些概况为人工嵌合体合成过程中的基因型分化，柑橘育种评估和供体选择提供了潜在的化学标记。