文献类型：期刊文献

英文题名：Exogenous GABA promotes adaptation and growth by altering the carbon and nitrogen metabolic flux in poplar seedlings under low nitrogen conditions

作者：Chen, Wei[1] Meng, Chen[2] Ji, Jing[1] Li, Mai-He[3,4,5] Zhang, Xiaoman[6] Wu, Yanyan[1] Xie, Tiantian[1] Du, Changjian[1] Sun, Jiacheng[1] Jiang, Zeping[7] Shi, Shengqing[1]

第一作者：Chen, Wei

通信作者：Shi, SQ[1]

机构：[1]Chinese Acad Forestry, Res Inst Forestry, State Key Lab Tree Genet & Breeding, Key Lab Tree Breeding & Cultivat,Natl Forestry &, Xiangshan Rd, Beijing 100091, Peoples R China;[2]Tech Univ Munich, Bavarian Ctr Biomol Mass Spectrometry, Gregor Mendel Str 4, D-85354 Freising Weihenstephan, Germany;[3]Swiss Fed Res Inst WSL, Forest Dynam, Zuercherstr 111, CH-8903 Birmensdorf, Switzerland;[4]Chinese Acad Sci, Inst Appl Ecol, CAS Key Lab Forest Ecol & Management, Erguna Forest Steppe Ecotone Res Stn, Wenhua Rd 72, Shenyang 110016, Peoples R China;[5]Northeast Normal Univ, Sch Geog Sci, Key Lab Geog Proc & Ecol Secur Changbai Mt, Minist Educ, Renmin St 268, Changchun 130024, Peoples R China;[6]Hebei Agr Univ, Coll Landscape Architecture, Lekai South St 2596, Baoding 071000, Peoples R China;[7]Chinese Acad Forestry, Res Inst Forest Ecol, Key Lab Forest Ecol & Environm, Natl Forestry & Grassland Adm, LXiangshan Rd, Beijing 100091, Peoples R China

年份：2020

卷号：40

期号：12

起止页码：1744-1761

外文期刊名：TREE PHYSIOLOGY

收录：;Scopus(收录号：2-s2.0-85096862374);WOS:【SCI-EXPANDED(收录号:WOS:000607844500008)】；

基金：We thank National Key R&D Program of China (2016YFD-0600105) and National Natural Science Foundation of China (31971627).

语种：英文

外文关键词：carbon metabolism; gamma-aminobutyric acid; nitrogen deficiency; nitrogen metabolism; Populus

摘要：Nitrogen (N) deficiency adversely affects tree growth. Additionally, gamma-aminobutyric acid (GABA) is closely associated with growth and stress responses because of its effects on carbon (C) and N metabolism. However, little is known about its roles related to plant adaptations to N-deficient conditions. In this study, we analyzed the effects of GABA (0, 2 and 10 mM) applications on the growth traits and physiological responses of poplar (Populus alba x P. glandulosa '84K') seedlings under high N (HN) and low N (LN) conditions. We found that the added GABA interacted with N to affect more than half of the studied parameters, with greater effects in LN plants than in HN plants. Under LN conditions, the GABA application tended to increase poplar growth, accompanied by increased xylem fiber cell length and xylem width. In stems, exogenous GABA increased the abundance of non-structural carbohydrates (starch and sugars) and tricarboxylic acid cycle intermediates (succinate, malate and citrate), but had the opposite effect on the structural C contents (hemicellulose and lignin). Meanwhile, exogenous GABA increased the total soluble protein contents in leaves and stems, accompanied by significant increases in nitrate reductase, nitrite reductase and glutamine synthetase activities in leaves, but significant decreases in those (except for the increased glutamate synthetase activity) in stems. A multiple factorial analysis indicated that the nitrate assimilation pathway substantially influences poplar survival and growth in the presence of GABA under LN conditions. Interestingly, GABA applications also considerably attenuated the LN-induced increase in the activities of leaf antioxidant enzymes, including peroxidase and catalase, implying that GABA may regulate the relative allocation of C and N for growth activities by decreasing the energy cost associated with stress defense. Our results suggest that GABA enhances poplar growth and adaptation by regulating the C and N metabolic flux under N-deficient conditions.