title: Growth under elevated air temperature alters secondary metabolites in Robinia pseudoacacia L. seedlings in Cd- and Pb-contaminated soils.
abstract: Plant secondary metabolites play a pivotal role in growth regulation, antioxidant activity, pigment development, and other processes. As the global climate changes, increasing atmospheric temperatures and contamination of soil by heavy metals co-occur in natural ecosystems, which alters the pH of rhizosphere soil and influences the bioavailability and mobility of metals. Elevated temperatures in combination with heavy metals are expected to affect plant secondary metabolites, but this issue has not been extensively examined. Here, we investigated secondary metabolites in Robiniapseudoacacia seedlings exposed to elevated temperatures using a passive warming device in combination with Cd- and Pb-contaminated soils. Heavy metals significantly stimulated the accumulation of saponins, phenolic compounds, and flavonoids in leaves and stems; alkaloid compounds increased in leaves and decreased in stems, and condensed tannins fluctuated. Elevated temperatures, alone and in combination with Cd and Pb, caused increases in secondary metabolites in the plant tissues. Phenolic compounds showed the greatest changes among the secondary metabolites and significant interactive effects of temperature and metals were observed. These results suggest that slightly elevated temperature could enhance protective and defense mechanisms of Robinia pseudoacacia seedlings exposed to heavy metals by stimulating the production of secondary metabolites.
authors.affiliation: The School of Earth Science and Resources, Chang'an University, Xi'an 710054, PR China.
authors.forename: Y H
authors.initials: YH
authors.lastname: Zhao
authors.affiliation: School of Environmental Science and Engineering, Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Key Laboratory of Environmental Protection & Pollution and Remediation of Water and Soil of Shaanxi Province, Chang'an University, No.126 Yanta Road, Xi'an 710054, PR China. Electronic address: jiaxianavy@163.com.
authors.forename: X
authors.initials: X
authors.lastname: Jia
authors.affiliation: School of Environmental Science and Engineering, Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Key Laboratory of Environmental Protection & Pollution and Remediation of Water and Soil of Shaanxi Province, Chang'an University, No.126 Yanta Road, Xi'an 710054, PR China.
authors.forename: W K
authors.initials: WK
authors.lastname: Wang
authors.affiliation: School of Environmental Science and Engineering, Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Key Laboratory of Environmental Protection & Pollution and Remediation of Water and Soil of Shaanxi Province, Chang'an University, No.126 Yanta Road, Xi'an 710054, PR China.
authors.forename: T
authors.initials: T
authors.lastname: Liu
authors.affiliation: School of Environmental Science and Engineering, Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Key Laboratory of Environmental Protection & Pollution and Remediation of Water and Soil of Shaanxi Province, Chang'an University, No.126 Yanta Road, Xi'an 710054, PR China.
authors.forename: S P
authors.initials: SP
authors.lastname: Huang
authors.affiliation: School of Environmental Science and Engineering, Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education, Key Laboratory of Environmental Protection & Pollution and Remediation of Water and Soil of Shaanxi Province, Chang'an University, No.126 Yanta Road, Xi'an 710054, PR China.
authors.forename: M Y
authors.initials: MY
authors.lastname: Yang
mesh_terms: D002104:Cadmium / Q000378:metabolism*; D057232:Global Warming; D007854:Lead / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D031301:Robinia / Q000254:growth & development* / Q000378:metabolism; D012989:Soil Pollutants / Q000378:metabolism*; D013696:Temperature
chemical_list: D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead
keywords: Cd-contaminated soils; Elevated air temperature; Pb-contaminated soils; Robinia pseudoacacia L. seedlings; Secondary metabolites