AUTHOR=He Minghui , Han Yanlong , Gao Yong , Han Min , Duan Liqing 

TITLE=Decoding the metabolomic responses of Caragana tibetica to livestock grazing in fragile ecosystems

JOURNAL=Frontiers in Plant Science

VOLUME=15

YEAR=2024

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2024.1339424

DOI=10.3389/fpls.2024.1339424

ISSN=1664-462X

ABSTRACT=<p>The population of <italic>Caragana tibetica</italic>, situated on the edge of the typical grassland-to-desert transition in the Mu Us Sandy Land, plays a vital ecological role in maintaining stability within the regional fragile ecosystem. Despite the consistent growth of <italic>C. tibetica</italic> following animal grazing, the biological mechanisms underlying its compensatory growth in response to livestock consumption remain unclear. Analyzing 48 metabolomic profiles from <italic>C. tibetica</italic>, our study reveals that the grazing process induces significant changes in the metabolic pathways of <italic>C. tibetica</italic> branches. Differential metabolites show correlations with soluble protein content, catalase, peroxidase, superoxide dismutase, malondialdehyde, and proline levels. Moreover, machine learning models built on these differential metabolites accurately predict the intensity of <italic>C. tibetica</italic> grazing (with an accuracy of 83.3%). The content of various metabolites, indicative of plant stress responses, including Enterolactone, Narceine, and Folcepri, exhibits significant variations in response to varying grazing intensities (<italic>P&lt;</italic>0.05). Our investigation reveals that elevated grazing intensity intensifies the stress response in <italic>C. tibetica</italic>, triggering heightened antioxidative defenses and stress-induced biochemical activities. Distinctive metabolites play a pivotal role in responding to stress, facilitating the plant’s adaptation to environmental challenges and fostering regeneration.</p>