The especial-early summer corn cultivar Jichengdan 3 was used to study the effects of topdressing time on nutrient uptake and dry matter accumulation of especial-early summer corn.The experiment was conducted in Jinzhong Basin,with two topdressing times,at jointing stage or at big flare stage.The results showed that the accumulation amount of N,P2O5 and K2O was 190.62 kg/ha,133.14 kg/ha and 320.45 kg/ha respectively when topdressed at big flare stage,markedly higher than at jointing stage.The absorption int...