## 1 Introduction  
Yunnan Province, located in the southwestern border of China, features an inland low-latitude region with a plateau and mountainous terrain, and a subtropical monsoon climate. These unique geographical conditions create ideal growing conditions for wild mushrooms, while also offering abundant resources for wild mushroom research. Currently, 882 species of wild mushrooms have been identified in Yunnan, accounting for 91% of the national total [1]. The boletes in Yunnan are highly diverse [2], exhibiting distinct characteristics in terms of morphology, color, and flavor. Boletes are rich in protein, carbohydrates, and minerals, with a low lipid content. Their nutritional value is comparable to meat, eggs, and milk, aligning with contemporary trends toward natural, healthy diets. In addition, the potential medicinal value of Boletus species is considerable, including the enhancement of the immune system, antioxidant effects, and anti-tumor properties [3; 4; 5]. However, research on these edible wild boletes remains scarce, and many bolete species have yet to be identified. _B. roseflavus_, a wild edible mushroom from the Boletaceae family and the Boletus genus, is known for its distinct coloration. Its cap ranges from light pink to rose, the stem is yellow to lemon-yellow with a red net-like pattern, and the fruiting body turns blue when damaged. Due to its unique aroma and taste, it is highly favored by consumers. Research on _B. roseflavus_ has been limited, primarily focusing on its biological activity and ecology [6; 7; 8]. To date, the compounds contributing to the distinctive \"white onion\" flavor of _B. roseflavus_ have not been comprehensively identified and analyzed. Furthermore, _B. roseflavus_ requires a specific ecological niche and complex symbiotic relationships for its growth, making artificial cultivation currently unfeasible. Therefore, sustainable harvesting practices are essential to avoid disrupting the local ecosystem. Mushroom flavor results from a delicate interplay between volatile and non-volatile compounds, and its formation is influenced by multiple factors. For instance, the volatiles in fresh _Flammulina velutipes_ are mainly composed of ketones and alcohols, with 3-octanone as the dominant component. Different packaging materials can alter its flavor during storage, while nano-packaging has been shown to slow the degradation of free amino acids, thereby preserving quality [9]. In _Agaricus bernardi_, the major volatile compounds include alcohols, ketones, and aldehydes--particularly 3-octanol, 3-octanone, 1-octen-3-ol, and benzyl alcohol. During storage, the contents of alcohols, aldehydes, hydrocarbons, and esters increase, whereas that of ketones declines [10]. Flavor profiles vary significantly among Boletus species with different genetic backgrounds. _Boletus edulis_ is characterized by a strong roasted and buttery aroma, primarily attributed to 3-(methylthio)propanal and 2,6-dimethylpyrazine. _Boletus aereus_ features a woody scent, with isovaleric acid, 2,6-dimethylpyrazine, phenylacetaldehyde, and (E)-2-octenal contributing notably to its flavor. _Boletus auringes_ is distinguished by its intense floral and smoky notes, with key contributors including isovaleric acid, 3-ethylphenol, and 2,6-dimethylpyrazine [11]. It is widely recognized that abiotic factors associated with geographic origin significantly affect crop yield and quality [12; 13; 14; 15], and such effects have also been observed in certain Basidiomycota mushrooms. For example, _Floccularia luteovirus_ from Tibet contains the highest levels of unsaturated fatty acids and proteins, while samples from Qinghai exhibit the highest polyphenol content, and those from Sichuan are richest in polysaccharides [16]. In _Pleurotus_ spp., samples from Indonesia show higher levels of gallic acid and p-hydroxybenzaldehyde, possibly due to tropical climate or cultivation conditions, whereas European samples are richer in osumaric acid and quercetin derivatives, likely influenced by strain or soil composition [17].