追肥时期对特早熟夏玉米氮磷钾吸收及干物质积累的影响

摘要

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 intensities of N,P2O5 and K2O all presented two peaks during the whole growth period,though they were all higher when topdressed at big flare stage [(2.14 kg/(ha · d),1.53 kg/(ha · d) and 3.44 kg/(ha · d),separately)].The biological yield and economic yield were markedly higher when topdressed at big flare stage,reaching to 13730.38 kg/ha and 5726.03 kg/ha respectively,which were 2.07％ and 5.98％ higher than those when topdressed at jointing stage.The economic coefficient was also improved.%为了给山西省晋中盆地生态条件下特早熟夏玉米合理施肥提供理论依据,选用特早熟夏玉米品种冀承单3号,在山西省晋中盆地麦收后硬茬播种,分别于拔节期、大喇叭口期进行追肥,研究追肥时期对特早熟夏玉米养分吸收及干物质积累的影响.结果表明,大喇叭口期追肥,特早熟夏玉米N、P2O5、K2O的累积吸收量分别为190.62、133.14、320.45 kg/hm2,均显著高于拔节期追肥.全生育期内N、P2O5、K2O的阶段吸收强度均出现2个高峰,大喇叭口期追肥三者平均吸收强度分别为2.14、1.53、3.44 kg/(hm2·d),均高于拔节期追肥.大喇叭口期追肥获得的生物产量和经济产量也显著高于拔节期追肥,分别为13730.38、5726.03 kg/hm2,较拔节期追肥分别增产2.07％和5.98％,提高了经济系数.