Biological Responses and Proteomic Changes in Maize Seedlings under Nitrogen Deficiency

The influence of nitrogen (N) deficiency on tolerance mechanisms in seedlings of two maize hybrids (Xu178 × Huang-C and Xu178 × Zong3) and their parental inbred lines (Xu178, Huang-C and Zong3), which show different nitrogen use efficiency (NUE), was investigated using physiological measurements combined with global proteomics profiling. The root fresh weight and chlorophyll a / b ratio were reduced significantly in Huang-C (low NUE) under 0.002 mM nitrate treatment for 10 days, whereas no significant change in these two traits was observed in Xu178 (high NUE) under the same treatment compared with N-sufficient treatment. Fifty and 56 protein spots, which showed more than two-fold changes in abundance at P