低氮胁迫下大豆根系的激素响应及代谢组学分析OA

In order to investigate the physiological mechanism and key differential metabolite regulation patterns of different low-nitrogen tolerant soybean genotypes under low nitrogen stress,the low-nitrogen tolerant cultivar Dongnong 59(Res)and the sensitive cultivar Changji Huangdou(Sus)were used as materials.The responses of root architecture,endogenous hormone contents,and metabolites to low nitrogen stress were analyzed under field conditions.The results showed that Dongnong 59 maintained better root growth,chlorophyll content,and root/shoot ratio by expanding root surface area and increasing root tip number.At the hormone level,Dongnong 59 upregulated GA3 content and maintained the balance of key hormone ratios to promote root expansion and antioxidant capacity,while Changji Huangdou had weaker regulation.Metabolomics analysis identified 3 131 differential metabolites,including 2 187 core metabolites between cultivars.Lipids maintained membrane stability,flavonoids alleviated oxidative damage,and amino acids supported root growth,with key pathways such as aminoacyl-tRNA biosynthesis significantly enriched.Correlation analysis confirmed the relationship between amino acid metabolites and root phenotypes.In conclusion,low-nitrogen tolerant soybeans adapt to low nitrogen stress through coordinated regulation of root morphology,hormone homeostasis,and metabolism.This study provides a theoretical basis for the breeding of low-nitrogen tolerant soybeans.