Impact of tea green leafhopper (Empoasca onukii) puncturing on the aroma profile of high-aroma oolong tea cultivars Jinguanyin and Jinmudan.

High-aroma Camellia sinensis cultivars Jinguanyin and Jinmudan are usually used to make black tea and lightly fermented oolong tea. The Oolong tea produced has a rich, lingering aroma and high quality. However, tea green leafhoppers can significantly reduce both yield and quality. Therefore, this study investigated the impact of varying degrees of tea green leafhopper damage on the volatile compounds of Oolong tea which made from Jinguanyin and Jinmudan according to the heavy-fermentation beauty tea process. The volatile profiles were analyzed by GC-MS. Results indicated that medium degree of puncturing by tea green leafhoppers enhanced the formation and accumulation of volatiles in Oolong tea made from Jinguanyin. We also found that Linalool, Geraniol, Dihydrolinalool and (Z)-linalooloxide(furanoid) were identified as key volatile compounds contributing to unique floral, fruity and sweet aroma of Jinguanyin and Jinmudan oolong tea. And the contents in JGYTM were the highest at 2749.98 μg/kg, 24751.63 μg/kg, 17131.17 μg/kg and 8172.35 μg/kg, respectively. The OAV values were 1833.32, 3300.22, 155.74 and 24,517.1, respectively. The content of geraniol in JMDTH was the highest at 22973.28 μg/kg, with an OAV value of 3063.1. The contents of linalool, dihydrolinalool and (Z)-linalooloxide(furanoid) were the highest in JMDTL, at 2207.25 μg/kg, 10080.36 μg/kg and 7441.64 μg/kg, respectively, with OAV values of 1471.5, 91.64 and 22,324.9, respectively. Therefore, the medium and low levels of puncture caused by the tea green leafhoppers respectively impart unique floral and fruity scents as well as sweet aromas to the Jinguanyin and Jinmudan Oolong teas. This study provides technical reference for the cultivation and management of Jinguanyin and Jinmudan, and provides theoretical basis for the improvement of raw materials and aroma of Oriental beauty tea in oolong tea.