Nitrogen utilisation and metabolism in maize ( Zea mays L.) plants under different rates of biochar addition and nitrogen input conditions

作者：Caixia Sun, L. Hao, D. Wang, Chen Li, Chun Hao Zhang, X. Chen, Jiabo Fu, Y.L. Zhang · 发表于：Plant Biology · 年份：2019 · DOI：10.1111/plb.12997 · 被引用次数：26 · 研究领域：Plant nutrient uptake and metabolism、Soil Carbon and Nitrogen Dynamics、Plant Micronutrient Interactions and Effects

Abstract Biochar (BC) application could improve plant nitrogen (N) utilisation and potentially reduce N fertiliser requirements. However, the fate of N in crop–soil systems and the metabolic responses of crops under conditions of BC co‐applied with reduced N are not well understood. The urea‐ 15 N isotope and pot experiments with three BC rates (0%, 5% and 15%; w/w) combined with three N fertiliser levels (100% N, 85% N and 55% N) were conducted for maize. The metabolome, 15 N abundance and gene expression in plants were analysed using nuclear magnetic resonance, gas isotope mass spectrometry and quantitative real‐time reverse transcription PCR, respectively. The results showed that recovery of N by maize ranged from 27.4% to 23.6% and decreased as the N application rate decreased (from 100% to 55%) without BC addition, but ranged from 24.6% to 29.4% when BC was added at a rate of 5% and increased as the N application rate decreased. BC addition had major effects on global metabolic profiles and metabolic networks at the metabolomics level as well as on the expression of related genes ( zmGS1 and zmAS1 ) and the content of mineral N (NO 3 − , NO 2 − and NH 4 + ) in maize seedlings; moreover, the interaction effects of the BC application rates and N fertiliser levels were evident ( P ≤ 0.001). BC addition induced a decrease in the flux toward sugar hydrolysis and maintained homeostasis in the amino acid pool, which was perturbed by reduced N levels; after which the maize plant...