Volatiles and Transcriptome Profiling Revealed the Formation of ‘Taro-like’ Aroma in the Leaf of Pumpkin (<i>Cucurbita moschata</i>)
Siying Zhao,
Yuehan Qiu,
Jianning Luo,
Wenwen Wang,
Haibin Wu,
Xiaoxi Liu,
Gangjun Zhao,
Hao Gong,
Xiaoming Zheng,
Yujuan Zhong,
Xian Yang,
Junxing Li
Affiliations
Siying Zhao
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Yuehan Qiu
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Jianning Luo
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Wenwen Wang
Agilent Technologies (China) Co., Ltd., Beijing 100102, China
Haibin Wu
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Xiaoxi Liu
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Gangjun Zhao
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Hao Gong
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Xiaoming Zheng
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Yujuan Zhong
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
Xian Yang
College of Horticulture, South China Agricultural University, Guangzhou 510640, China
Junxing Li
Guangdong Key Laboratory for New Technology Research of Vegetables, Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China
‘Taro-like’ odor is an important economic trait of pumpkin species. The metabolic and molecular bases of this aromatic trait remain largely unexplored. Therefore, in this study, gas chromatography-mass spectrometry, GC-Olfactometry, and RNA-seq technology were used to illuminate the differential volatile compounds, the key volatile compounds, and differentially expressed genes (DEGs) in leaves from two pumpkin samples. Eight volatile compounds, including (E)-2-nonenal, 3-octanol, 2-ethyl-1-hexanol, 1-nonanol, α-terpineol, 2,3-pentanedione, caryophyllene, and 2-acetyl-1-pyrroline, were only detected in the sample with ‘taro-like’ aroma. Moreover, the variable importance in projection scores of all the above eight volatile compounds were >1.0 using PLS-DA analysis. The compounds 2-acetyl-1-pyrroline, 3-octanol, 1-nonanol, and (E)-3,7-dimethyl-2,6-octadienal were identified as the key contributors using GC-Olfactometry analysis. It was determined that 2-acetyl-1-pyrroline might play a significant role in ‘taro-like’ aroma. Furthermore, most of the differential volatile compounds were derived from fatty acids, and the DEGs were also involved in the pathways related to degradation, metabolism, and biosynthesis of fatty acids. Moreover, five genes involved in the accumulation of 2-acetyl-1-pyrroline showed differential expression, and their expression trends were consistent with 2-acetyl-1-pyrroline. This study offers the basis for further studies on the mechanism of ‘taro-like’ aroma in pumpkins.
