Effects of industrial vitamin C production-residue after evaporation on nitrogen utilization and quality of non-heading Chinese cabbage
Promoting the uptake and assimilation of nitrogen fertilizer is crucial for improving crop yield and quali-ty.However,the effect of low-molecular-weight organic matters on soil nitrogen utilization by plants remains un-clear.Here,we investigated the effect of industrial vitamin C production-residue after evaporation(RAE),which is mainly composed of small-molecule organic acids,on the utilization of soil nitrogen by non-heading Chinese cab-bage(Brassica campestris ssp.chinensis).The results showed that RAE application increased nitrogen fertilizer ag-ronomic efficiency,nitrogen fertilizer partial productivity,nitrogen fertilizer physiological efficiency,and nitrogen fertilizer apparent efficiency by 171.2%,57.9%,46.1%,and 86.1%,respectively.Plant growth was significantly promoted,with an increase of total nitrogen accumulation and biomass of leaves by 60.7%and 57.9%,respective-ly.Meanwhile,chlorophyll content was increased by 16.7%,and soluble protein and free amino acid contents were increased by 65.4%and 15.1%,respectively.Furthermore,the expression levels of nitrite reductase,glutamine synthetase,and glutamate synthase were up-regulated,indicating that photosynthesis was enhanced and inorganic nitrogen assimilation was significantly promoted.In conclusion,RAE could improve nitrogen use efficiency,yield and quality of non-heading Chinese cabbage.This study provided a scientific basis for resource utilization of RAE as a potential organic synergist for improving nitrogen fertilizer utilization.
organic acidnon-heading Chinese cabbagenitrogen fertilizerassimilationnitrogen use efficiency