Zheng Bao-Qiang, Li Xiao-Qing, Wang Yan
Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
Plants (Basel). 2023 Jan 9;12(2):304. doi: 10.3390/plants12020304.
Orchid flowers have a unique structure that consists of three sepals and three petals, with one of the petals forming the labellum (lip) that can be differentiated into the hypochile and epichile. In orchids, the emission of floral scent is specific and spatially complex. Little is understood about the molecular and biochemical mechanisms of the differing scent emissions between the parts of orchid flowers. Here, we investigated this in the hybrid KOVA, and our study showed that monoterpenes, including linalool and geraniol, are the main components responsible for the KOVA floral scent. The KOVA flower was scentless to the human nose before it reached full bloom, potentially because the s (s) and s (s) that biosynthesize monoterpenes were highly expressed in flowers only when it reached full flowering. Additionally, the spatial expression profile of the (s), which were highly expressed in the basal region of the lip (hypochile), contributed to the highest monoterpene emissions from this part of the flower. This might have caused the hypochile to be more fragrant than the other parts of the flower. These findings enrich our understanding of the difference in scents between different flower parts in plants and provide information to breed novel orchid cultivars with special floral scents.
兰花具有独特的结构，由三个萼片和三个花瓣组成，其中一个花瓣形成唇瓣，可分为下唇和上唇。在兰花中，花香的散发具有特异性且在空间上较为复杂。对于兰花花朵不同部位散发不同香味的分子和生化机制，人们了解甚少。在此，我们以杂交品种KOVA进行了研究，我们的研究表明，包括芳樟醇和香叶醇在内的单萜类化合物是KOVA花香的主要成分。KOVA花在完全绽放之前对人鼻是无味的，这可能是因为生物合成单萜类化合物的s（s）和s（s）仅在花朵完全开放时才在花中高表达。此外，在唇瓣（下唇）基部区域高表达的（s）的空间表达谱，导致花朵该部位单萜类化合物的排放量最高。这可能使得下唇比花朵的其他部位更香。这些发现丰富了我们对植物不同花部之间香味差异的理解，并为培育具有特殊花香的新型兰花品种提供了信息。
