文献类型：期刊文献

英文题名：Morphological, physiological, and transcriptional responses to low nitrogen stress in Populus deltoides Marsh. clones with contrasting nitrogen use efficiency

作者：Chen, Cun[1,2] Chu, Yanguang[1,2] Huang, Qinjun[1,2] Zhang, Weixi[1,2] Ding, Changjun[1,2] Zhang, Jing[1,2] Li, Bo[1,2] Zhang, Tengqian[1,2] Li, Zhenghong[1,2] Su, Xiaohua[1,2,3]

第一作者：Chen, Cun

通信作者：Su, XH[1];Su, XH[2];Su, XH[3]

机构：[1]Chinese Acad Forestry, Res Inst Forestry, State Key Lab Tree Genet & Breeding, Beijing, Peoples R China;[2]State Forestry & Grassland Adm, Key Lab Tree Breeding & Cultivat, Beijing, Peoples R China;[3]Nanjing Forestry Univ, Coinnovat Ctr Sustainable Forestry Southern China, Nanjing, Jiangsu, Peoples R China

年份：2021

卷号：22

期号：1

外文期刊名：BMC GENOMICS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000700433100003)】；

基金：This research was funded by the National Natural Science Foundation of China (Grant No. 31670677), and the Basic Research Fund of RIF (Grant No. CAFYBB2020SZ002 and CAFYBB2017ZA001-3).

语种：英文

外文关键词：Nitrogen deficiency; Nitrogen use efficiency; Gene expression; Populus deltoides Marsh

摘要：Background Nitrogen (N) is one of the main factors limiting the wood yield in poplar cultivation. Understanding the molecular mechanism of N utilization could play a guiding role in improving the nitrogen use efficiency (NUE) of poplar. Results In this study, three N-efficient genotypes (A1-A3) and three N-inefficient genotypes (C1-C3) of Populus deltoides were cultured under low N stress (5 mu M NH4NO3) and normal N supply (750 mu M NH4NO3). The dry matter mass, leaf morphology, and chlorophyll content of both genotypes decreased under N starvation. The low nitrogen adaptation coefficients of the leaves and stems biomass of group A were significantly higher than those of group C (p < 0.05). Interestingly, N starvation induced fine root growth in group A, but not in group C. Next, a detailed time-course analysis of enzyme activities and gene expression in leaves identified 2062 specifically differentially expressed genes (DEGs) in group A and 1118 in group C. Moreover, the sensitivity to N starvation of group A was weak, and DEGs related to hormone signal transduction and stimulus response played an important role in the low N response this group. Weighted gene co-expression network analysis identified genes related to membranes, catalytic activity, enzymatic activity, and response to stresses that might be critical for poplar's adaption to N starvation and these genes participated in the negative regulation of various biological processes. Finally, ten influential hub genes and twelve transcription factors were identified in the response to N starvation. Among them, four hub genes were related to programmed cell death and the defense response, and PodelWRKY18, with high connectivity, was involved in plant signal transduction. The expression of hub genes increased gradually with the extension of low N stress time, and the expression changes in group A were more obvious than those in group C. Conclusions Under N starvation, group A showed stronger adaptability and better NUE than group C in terms of morphology and physiology. The discovery of hub genes and transcription factors might provide new information for the analysis of the molecular mechanism of NUE and its improvement in poplar.