玉米耐低氮基因型筛选时期的初步探讨

采用溶液培养法研究了贵州省喀斯特高原生态型玉米品种贵毕303不同时期氮素营养对玉米缺氮症状、形态特征、生物学产量及氮素营养状况的影响及其差异。结果表明,不同时期供氮对贵毕303的缺素症状、地上部和地下部的生物学产量、生物学形态特征及植株氮素营养状况产生不同程度的影响,其中以玉米的生物产量、根系体积、植株总吸氮量及缺素症状表现更为突出,可明显地反映贵毕303氮素营养特征的阶段性或时期性。根据植物营养临界期定义,该玉米品种的三叶期后完全营养液培养供应时期或近4叶期是玉米氮素营养基因型材料筛选的关键时期。

Discussion on the Critical Period of Screening Genotypes with Tolerant to Lower Nitrogen Level in Maize

Guibi 303,a maize variety with the plateau ecological type,was cultivated by the nutrition solution to investigate effects of nitrogen nutrition provided at different growth stage on the nitrogen deficiency symptom,morphological character,biomass and plant nitrogen nutrition situation.The results show that providing nitrogen at different growth stage has the important effects on the biomass,root size,total absorbing nitrogen amount and nitrogen deficiency symptom,which can express the phase and period character of nitrogen nutrition characteristic.The key period for screening genotypes with tolerant to lower nitrogen level from Guibi 303 is during three-leaf and near four-leaf stage under the complete nutrition solution according to the critical period definition of plant nutrition.