Affiliation:
1. College of Horticulture, Shanxi Agricultural University, Jinzhong 030801, China
Abstract
The absorption and utilization of NH4+ and NO3− by plant roots is closely related to soil moisture. In this study, we investigated the effect of short-time drought and rewatering on uptake and assimilation of NH4+ and NO3− in 1-year-old Malus hupehensis plants, as well as transcription changes of ammonium transporters (AMTs) and nitrate transporters (NRTs). In roots, the NH4+ and NO3− content and nitrate reductase activity decreased under drought and to some extent was restored after rewatering. Expression analysis indicated that most investigated AMTs and NRTs were down-regulated while MhAMT1;2 was significantly up-regulated in drought-stressed roots. Therefore, the function of MhAMT1;2 was further studied through bioinformatics analysis, tissue-specific expression, subcellular localization, and functional complementation in NH4+ uptake-defective yeast and Arabidopsis mutants. Results showed that MhAMT1;2 was mainly expressed in roots and localized to the cell membrane. Moreover, MhAMT1;2 can mediate NH4+ uptake in both yeast and Arabidopsis mutants, and the transport process was affected by external proton concentrations and ATP. The present study will create a basis for exploring the functional roles of plant AMT members and improving N uptake and use efficiency under drought condition in fruit trees.
Funder
Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi
Scientific and Technological Research and Extension Program of Water Conservancy in Shanxi Province
PhD Start-up Fund of Shanxi Province
Technology Innovation Fund of Shanxi Agricultural University
Subject
Horticulture,Plant Science
Reference45 articles.
1. Membrane Transporters for Nitrogen, Phosphate and Potassium Uptake in Plants;Chen;J. Integr. Plant Biol.,2008
2. Root nitrogen acquisition and assimilation;Miller;Plant Soil,2004
3. Nitrate uptake ability by maize roots during and after drought stress;Buljovcic;Plant Soil,2001
4. Drought effect on plant nitrogen and phosphorus: A metaanalysis;He;New Phytol.,2014
5. Du, Y., Zhao, Q., Chen, L., Yao, X., and Xie, F. (2020). Effect of drought stress at reproductive stages on growth and nitrogen metabolism in soybean. Agronomy, 10.