Effects of seed mass,nutrient content and nutrient reserve on dry biomass and nitrogen,phosphorus and potassium partition in the seedlings of 16 maize cultivars, and their susceptibility to external nutrient supply were conducted by using a sand experiments. The result showed that,seed nutrient reserve was significant positively associated with roots,sheath and straw,and leaf biomass of maize seedling without external nutrients supply ( con-trol). External nutrients supply increased biomass of maize seedling,range (by 80. 8%) and coefficient of variation (CV) of root∶shoot ratio (by 118. 2%),while reduced root∶shoot ratio,and CV of biomass in roots,sheath and straw,and leaf,when compared with the control. Nutrient supplied seedling showed the maximum increase in root, sheath and straw,and leaf potassium content over phosphorus content and nitrogen content. In addition,External nu-trients supply reduced CV of potassium content in all parts of the seedling,and in the leaves showed the maximum reduction. By contrast,increase in both of nitrogen content in the seedlings and its CV was observed under nutrient supply condition in compared with the control. The increase in CV of root nitrogen content was higher than that of sheath and straw,and leaf nitrogen content. Furthermore,external nutrients supply increased root phosphorus con-tent,and CV of phosphorus content in sheath and straw, and leaf significantly, when compared with the control. However ,seedling had the highest CV of phosphorus content in roots under the two conditions. Among mineral nutri-ents reserve,Potassium is the first to become depleted from the seed. Clustering analysis on seed and seedling traits indicated that Zhengdan 958,used as a standard control cultivars in the national new cultivars certification experi-ment,was different from the other 15 maize cultivars in seed and seedling traits,because of the lowest increase in ni-trogen and phosphorus accumulation,nitrogen and potassium depletion under nutrient supply,and no obvious change in root∶shoot ratio,root nitrogen and potassium content of the cultivars response to external nutrients supply,while increase in potassium accumulation was slightly higher than that in Nongda 108,and all of which might be the main reason for wide ecological fitness in Zhengdan 958 .%采用砂培培养的方法，以16个玉米杂交种为供试材料，研究粒重、籽粒中贮存的氮磷钾养分含量和贮量对干物质及养分在苗期玉米根、茎、叶中的分配和养分敏感性的影响。结果表明，籽粒养分贮量与苗期无外源养分供应(对照)条件下玉米根、茎、叶的生物量均存在显著的正相关关系(氮贮量与叶片生物量的相关关系除外)。与对照相比，供应外源养分提高了苗期玉米的生物量，但明显降低了其根冠比，且在降低根、茎、叶生物量的变异系数的同时，明显提高了根冠比的极差和变异系数(二者的增高幅度分别高达80.8%和118.2%)。供应外源养分对提高苗期玉米的植株及其根、茎、叶钾含量的效应较氮和磷含量明显，但却明显降低钾含量的变异系数，并以叶的变异系数的降低幅度最大。与此不同，供应外源养分同时提高苗期玉米植株及根、茎、叶的含氮量及其变异系数，且以根系含氮量的变异系数增高最明显。此外，与对照相比，供应外源养分还可明显提高玉米的根系含磷量，且除了根系外，植株及茎和叶含磷量的变异系数均呈升高趋势；但无论有无外源养分，根系含磷量的变异系数始终明显高于茎和叶。在幼苗生长过程中，籽粒中养分的耗竭速率从快到慢依次为：钾、氮、磷。通过对籽粒和幼苗生长的相关性状进行聚类分析发现，在供试玉米品种中，国审对照品种郑单958与其他15个品种存在明显的差异：外源养分对郑单958的根冠比、根系含氮量和含钾量的影响相对最低；且郑单958籽粒中的氮和钾的耗竭百分比以及在供应外源养分后，新增氮和磷的累积量也均为最低，仅新增钾的累积量略高于农大108。这些特性可能是郑单958具有生态广适性的主要原因。
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