采用溶液培养方法,研究了4个玉米品种苗期生长及养分吸收利用对氮、磷、钾亏缺的响应及基因型差异.结果表明,与全营养对照相比,氮、磷、钾亏缺下4个玉米品种的根干重、根体积、根条数、地上干重、单株叶面积、株高、茎粗均下降,但对同一种营养元素亏缺的响应程度存在基因型差异.氮亏缺下,郑单958的根长增幅,根干重、根体积及根系氮、磷、钾含量的降幅均显著小于浚单20、先玉335和登海662,且氮素利用效率增幅和养分转运率降幅也均最大;磷亏缺下,先玉335、登海662和郑单958相对根干重、相对根体积和相对根系钾含量显著小于浚单20,且浚单20的干重降幅最小,先玉335和郑单958次之,登海662干重降幅最大;钾亏缺下,先玉335相对地上干重和相对地上部养分含量均最大.在氮、磷、钾同等程度亏缺条件下,氮亏缺对玉米苗期生长影响最大,磷亏缺次之,钾亏缺影响最小;且4个品种表现为如下差异:耐低氮能力为郑单958＞先玉335＞浚单20＞登海662,耐低磷能力为浚单20＞先玉335＞郑单958＞登海662,耐低钾能力为先玉335＞郑单958＞登海662＞浚单20.%Four maize cultivars, Xundan 20, Xianyu 335, Denghai 662 and Zhengdan 958 used as testing materials, a nutrient solution culture experiment was conducted to investigate responses of 8rowth and nutrient uptake and utilization among four maize cultivars to nitrogen, phosphorus and potassium deficiency at seedling stage. The results showed that root dry weight, root volume, root number, shoot dry weight, leaf area per plant, plant height and stem diameter all decreased under N -,P -, K - deficient condition. However, compared with plants under N,P, K control, the response degree of four cultivars to the same nutrient element deficiency was different. Under N - deficient condition, the increase of root length and N use efficiency, and the decrease of root dry weight, root volume, N, P, K content of root, transport ratio of N, P and K of Zhengdan 958 were significantly less than those of other three cultivars. Under P -deficient condition, the relative root dry weight, relative root volume and relative K content of root of Xianyu 335, Denghai 662 and Zhengdan 958 were significantly smaller than those of Xundan 20, and the decrease of dry weight of Xundan 20 was least,Xianyu 335 and Zhengdan 958 coming next, Denghai 662 the third. Under K - deficient condition, the relative shoot dry weight and relative N, P, K content of shoot of Xianyu 335 reached the highest. Under the same deficiency level, the effect of nutrients deficiency on maize growth at seedling stage was N deficiency ＞ P deficiency ＞ K deficiency, and response differences of four maize cultivars to N, P, K were presented as, capacity of tolerance to low N -: Zhengdan 958 ＞ Xianyu 335 ＞ Xundan 20 ＞ Denghai 662, capacity of tolerance to low P -: Xundan 20 ＞ Xianyu 335 ＞ Zhengdan 958 ＞ Denghai 662; capacity of tolerance to low K -: Xianyu 335 ＞ Zhengdan 958 ＞ Denghai 662 ＞ Xundan 20.
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