# Analysis of Floral Fragrance Components in Different Parts of _Iris typhifolia_
## 1 Introduction  
Floral fragrances are composed of various secondary metabolites emitted by natural flowers; thus, a unique aroma is given. Floral fragrance plays a crucial role in attracting pollinators, communicating with them [1], enhancing plant esthetics, and contributing to the secondary metabolism of ornamental plants. Iris, one of the \"three root-rooted flowers in the world\", is a well-known fragrant flower with significant decorative value [2; 3; 4]. _Iris typhifolia_ Kitag, a perennial herb in the Iris family, is mainly distributed in Heilongjiang, Jilin, Liaoning, and Inner Mongolia in China. Due to its landscape value, _Iris typhifolia_ is often used to decorate flower beds and edgeadows and can also be scattered in streams, pools, and lakes. It has a prominent role in regulating the microclimate, soil and water conservation, and wind and dust prevention and contributes to maintaining environmental balance, improving urban ecological environment, and enhancing community stability [5].  
It is worth noting that _Iris typhifolia_ can also produce a unique floral fragrance, which not only increases the ornamental value of flowers but also has high economic and medicinal value, such as being used to make perfume, soap, cosmetics, etc. As a tobacco additive, irisone can improve the flavor and quality of tobacco [6]. Therefore, it is crucial to determine the main fragrant parts of _Iris typhifolia_.  
Currently, the primary methods for studying the components of _Iris typhifolia_ are distillation extraction, gas chromatography-mass spectrometry (GC-MS), solid-phase microextraction (SPME), and electronic nose sniffing. For example, [PERSON] et al. extracted the flower essential oils of _Iris seudacorus_ and _Iris kerneriana_ by distillation and detected 52 and 54 volatile components by GC-MS, among which the contents of alkanes and acids were the highest [7]. However, the distillation extraction process may lead to the loss of some substances, which cannot reflect the original components of flowers. In contrast, the solid-phase microextraction method simulates the release process of flowers in nature. This method requires fewer samples but is more efficient, convenient, and sensitive, making it promising to extract the volatile components of flowers [8]. A total of 75 compounds were detected from yellow _Iris lutscens_ by SPME combined with GC-MS, while 69 compounds were detected from purple _Iris lutscens_, and it was found that terpen were the main volatile components [9]. [PERSON] et al. applied SPME-GC-MS and found that the main volatile components of _Iris barbata_ were cryophyllene, linalool, citronella, methyl cinnamate, \(\beta\)-cyclene, rohanperene, methyl myristate, linalool acetate, isosafrole, nerool, and geraniol [10].  
So far, studies on the floral components of _Iris typhifolia_ have only focused on the whole flower, without examining the separation of different parts of the flower, which greatly limits studies on the floral components of _Iris typhifolia_ and is not conducive to the development and subsequent utilization of different fragrance varieties. In this study, we used solid-phase microextraction (SPME), gas chromatography-mass spectrometry (GC-MS), and an electronic nose to compare the volatile components of _Iris typhifolia_ and determine the source of the fragrance-releasing substances of _Iris typhifolia_. The research results can identify the specific fragrance-releasing site of _Iris typhifolia_ and lay a foundation for the future breeding of new varieties. The data involved in this study can be found in the Supplementary Materials.