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

• DOI: 10.1093/treephys/tpaa101
• Publication Date: 2020-08-07T11:33:28Z
• Authors: Wei Chen; Chen Meng; Jing Ji; Mai-He Li; Xiaoman Zhang; Yanyan Wu; Tiantian Xie; Changjian Du; Jiacheng Sun; Zeping Jiang; Shengqing Shi
• Keywords: Carbon fibers; Nitrogen Cycle

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