Physiological, transcriptomic, and metabolomic analyses reveal that Pantoea sp. YSD J2 inoculation improves the accumulation of flavonoids in Cyperus esculentus L. var. sativus
Saisai Wang,
Yanna Huang,
Yu Sun,
Jinbin Wang,
Xueming Tang
Affiliations
Saisai Wang
School of Agriculture and Biology, Shanghai Jiao Tong University, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China
Yanna Huang
School of Agriculture and Biology, Shanghai Jiao Tong University, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China
Yu Sun
Biotechnology Research Institute Key Laboratory of Agricultural Genetics and Breeding, Shanghai Academy of Agricultural Sciences, Beidi Road 2901, Minhang District, Shanghai, 201106, PR China
Jinbin Wang
Biotechnology Research Institute Key Laboratory of Agricultural Genetics and Breeding, Shanghai Academy of Agricultural Sciences, Beidi Road 2901, Minhang District, Shanghai, 201106, PR China
Xueming Tang
School of Agriculture and Biology, Shanghai Jiao Tong University, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Key Laboratory of Urban Agriculture, Ministry of Agriculture and Rural Affairs, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Shanghai Yangtze River Delta Eco-Environmental Change and Management Observation and Research Station, Ministry of Science and Technology, Ministry of Education, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China; Corresponding author. School of Agriculture and Biology, Shanghai Jiao Tong University, Dongchuan Road 800, Minhang District, Shanghai, 200240, PR China.
Plant growth-promoting microorganisms (PGPMs), such as Pantoea sp. YSD J2, promote plant development and stress resistance, while their role in flavonoids accumulation still needs to be further understood. To investigate the complex flavonoid biosynthesis pathway of Cyperus esculentus L. var. sativus (tigernut), we compared Pantoea sp. YSD J2 inoculation (YSD J2) and water inoculation (CK) groups. YSD J2 significantly elevated the content of indole-3-acetic acid (IAA) and orientin. Furthermore, when analyzing flavonoid metabolome, YSD J2 caused increased levels of uralenol, petunidin-3-O-glucoside-5-O-arabinoside, luteolin-7-O-glucuronide-(2 → 1)-glucuronide, kaempferol-3-O-neohesperidoside, cyanidin-3-O-(2″-O-glucosyl)glucoside, kaempferol-3-O-glucuronide-7-O-glucoside, quercetin-3-O-glucoside, luteolin-7-O-glucuronide-(2 → 1)-(2″-sinapoyl)glucuronide, and quercetin-4′-O-glucoside, which further enhanced antioxidant activity. We then performed RNA-seq and LC-MS/MS, aiming to validate key genes and related flavonoid metabolites under YSD J2 inoculation, and rebuild the gene-metabolites regulatory subnetworks. Furthermore, the expression patterns of the trans cinnamate 4-monooxygenase (CYP73A), flavonol-3-O-L-rhamnoside-7-O-glucosyltransferase (UGT73C6), shikimate O-hydroxycinnamoyltransferase (HCT), chalcone isomerase (CHI), flavonol synthase (FLS), and anthocyanidin synthase (ANS) genes were confirmed by qRT-PCR. Additionally, 4 transcription factors (TF) (especially bHLH34, Cluster-37505.3) under YSD J2 inoculation are also engaged in regulating flavonoid accumulation. Moreover, the current work sheds new light on studying the regulatory effect of Pantoea sp. YSD J2 on tigernut development and flavonoid biosynthesis.
