【摘要】 采用盆栽试验研究氮肥不同施用时期下春玉米早衰特性。结果表明,合理的增加追肥次数能提高穗粒数和千粒重,进而提高玉米的籽粒产量。当氮肥分别在基施、拔节期与大喇叭口期1∶3∶1施用时,春玉米生育后期的穗叶叶绿素含量和SOD活性较一次性基施有不同程度的提高,而叶片形态指标和丙二醛(MDA)含量却降低,有效地延缓了玉米的衰老。对照(无氮肥)处理的穗叶叶绿体破裂解体,基粒和基质片层结构膨胀,导致叶片的叶绿素含量下降、光合能力降低而出现早衰。更多还原

【Abstract】 By pot experiment,the behaviors of early senescence of spring maize were studied under different fertilizing time.The results showed that the proper increase of the times of fertilizer application could enhance the ear grain number and 1000-grain weight.When the fertilizer application in base fertilizer,jointing stage and big bell mouth stage was 1∶3∶1,the chlorophyll content and SOD activity were all higher than that in single basal application,but lamina shape and MDA content were in adverse,which could delay the early senescence effectively.The degradation of chloroplast and the dilation of granum lamellae in CK treatment resulted in the reduction of leaf chlorophyll content and photosynthetic capacity and early senescence.更多还原