Conservation agriculture raises crop nitrogen acquisition by amplifying plant-microbe synergy under climate warming

Sustainable crop production in a warming climate requires land management strategies that support plant-soil-microbe interactions to optimize nitrogen (N) availability. Here, we investigate the interacting effects of 10 years’ experimental warming and management (conservation vs. conventional agriculture) on wheat N acquisition using in situ 15N-labeling, root metabolomics and microbial metagenomics. We find that warming amplifies the positive effects on wheat nitrate uptake by 25% in conservation agriculture compared to conventional agriculture, while alleviating microbial competition for N. Additionally, warming increases soil gross N mineralization and nitrification rates by 191% and 159%, but decreases microbial immobilization by 24% in conservation agriculture. Concurrently, microbial genes for mineralization and nitrification are enriched, while those for N immobilization and nitrate reduction are reduced under conservation agriculture with warming. These shifts are driven by alterations in root primary and secondary metabolites, which reshape N-cycling microbial functional niches and optimize multiple microbial N processes beyond mere organic N mining. This reconfiguration increases carbon-nitrogen exchange efficiency, enabling wheat to outcompete soil microorganisms for N. Collectively, our findings suggest that conservation agriculture enhances plant N acquisition by strengthening plant-soil-microbe interactions under climate change, providing a sustainable strategy for future food security.

This study was supported by the Major Science and Technology Project of Shandong Province (2024CXPT075), National Natural Science Foundation of China (grant no. U23A20158), National Key R&D Program of China (2022YFD1901300; 2023YFD1901500), 2115 Talent Development Program of China Agricultural University and Beijing Advanced Disciplines and Strategic Priority Research Program of the Chinese Academy of Sciences (XDA28130301). Contribution of A.K. is supported by funds #12S153 and 12R254.

Peer reviewed