高量施锌肥对玉米Zn吸收和积累及产量的影响

在田间试验条件下,研究正常施锌(10kg/hm2,25kg/hm2 ZnSO4.7H2O)和超高量施锌处理(50kg/hm2,100kg/hm2,150kg/hm2 ZnSO4.7H2O),对玉米各个生育期植株锌吸收和积累以及产量的影响,以期为玉米增产、品质改善和合理施锌肥提供科学依据。结果表明:在施锌肥量10～150kg/hm2范围内,玉米苗期、拔节期、吐丝期、灌浆期、成熟期的植株和籽粒含锌量都有显著增加的趋势,并且施用量与锌含量呈极显著正相关,正常施锌和超高量施锌在植物体内各个生育期锌含量都呈增加的趋势,且同一浓度施锌量,玉米植株积累的锌量随植株生长而增加,说明玉米在不同生长期从土壤中吸取的锌元素也在不断增加。玉米地上部分各生育阶段对锌的吸收速率总体趋势为,随着施锌量的增加各个生育阶段对锌的吸收速率呈增加趋势,其中,拔节期-吐丝期对锌的吸收速率最高。随着施锌量的增加,玉米产量呈现先增加后降低的趋势,最适合的施锌量为50kg/hm2,相比正常施锌量有所提高,并且高施锌肥可以增加玉米产量、提高玉米籽粒和植株锌含量。

Influence of High-application of Zinc Fertilizers on Absorption and Accumulation of Zn Content and Maize Yield

Field experiment studied that the absorption and accumulation of Zn content and maize yield were influenced by an artificial increase of application of Zn fertilizer(50,100,150 kg/hm2 ZnSO4·7H2O)based on normal application of Zn fertilizer(10 kg/hm2,25 kg/hm2,ZnSO4·7H2O).The results showed Zn content of maize plants and grains had a significant increasing trend within the range 10~150 kg/hm2 during seedling stage,jointing stage,heading stage,filling stage and maturity period.There was a significant positive correlation between the application of Zn fertilizer and Zn content.And the accumulated Zn content increased with the growth of plants with the same application of Zn fertilizer,which indicated that maize had an increasing absorption of Zn from the soil at different growth stages.Overall,Zn uptake rate increased with the increase of application of Zn fertilizer on the ground part of maize at each growth stage,with the maximum of Zn uptake rate in the jointing stage and heading stage.The maize yield increased thanks to the increase of Zn application,but reduction was still visible due to excessive application of Zn fertilizer.The optimal application was 50 kg/hm2.However,maize with high-applied Zn fertilizer had better yield and Zn content of grain and plants than that with normal application of Zn fertilizer.