In the present study, the relationship between cytokinin andcorn compensatory growth deserved much more attention. Underthe addition of NO3−to roots and after rewatering, among the fourplant hormones ZR, IAA, GA3and ABA, higher leaf ZR concentrationwas observed in corn seedlings of the rewatering group comparedwith the wet treatment group. Moreover, compensatory growthoccurred simultaneously with increase in leaf ZR concentration.On the contrary, without the addition of NO3−to roots, no com-pensatory growth occurred, and no high leaf ZR concentration wasfound upon rewatering treatment compared with wet treatment.Niu et al. (2009) and Luo et al. (2013) reported that rewateringafter drought stress increased the leaf cytokinin concentration inpea and cotton. In addition, when exogenous cytokinin was addedto leave, the increased ZR concentration in leaves led to compen-satory growth after rewatering. Thus, leaf cytokinin was closelyrelated to compensatory growth upon post-drought rewatering.