在缺磷胁迫下，对磷低效、磷吸收高效和利用高效3个小麦品种及其杂种F1的磷吸收、利用特性进行了研究。结果表明，与磷低效品种Nc37相比，磷吸收高效品种81(85)单株次生根数较多、次生根直径较大、根系干物质重量较大、TTC（氯化三苯基四氮唑）还原力较高和单株全磷量较多。其对磷素吸收量的增加，是根系形态和根体构型改变和对土壤中难溶性磷素利用能力增强两方面共同作用的结果。利用高效品种（蚂蚱麦）具有较高的旗叶酸性磷酸化酶活性和较高的磷利用效率，对于改善植株体内磷的代谢周转和再利用能力，进而提高植株的磷利用效率可能具有较重要作用。在F1-1 [Nc37×81(85)], F1-2 (Nc37×蚂蚱麦)和 F1-3 [81(85) ×蚂蚱麦]3个杂种F1中，单株次生根数、次生根粗度、单位土体根系干重、根系TTC还原力、植株成熟期全磷量和旗叶酸性磷酸化酶活性的离中优势（Hm）和超高亲优势（Hh）多为正向优势。其单株籽粒产量的Hm和Hh均为正值，分别变化在31.7%~32.8%（Hm）和18.5%~29.6%（Hh）之间。用高效吸收、利用2个不同类型的小麦品种作亲本配制杂交组合，充分利用F1代在磷吸收利用上的杂种优势，对于改善在磷胁迫下小麦的磷素营养可能具有重要作用。
Three wheat (Triticum aestivum L.) cultivars with different phosphorus (P) efficiency and the hybrid F1s from the careers between three cultivars were used to compare phosphorus acquisition and utilization properties under P-deficient conditions. As compared with cultivar with low P efficiency (Nc37), cultivar with high P acquisition efficiency [81(85)] had much more secondary root number per plant, larger diameter of secondary root, higher root dry weight per cm3 soil（Fig.1）, higher TTC reductive activity in root and much more accumulation of P in plant(Fig.2, 3). Its increase of P uptake under P-deficient condition was due to the changes of root amount and the enhancement of acquisition of insoluble phosphorus from the soil. The higher APase activity in flag leaf possibly had important role to improve the utilization efficiency of P in cv. Mazhamai by promoting the metabolic circling and re-utilization of P in plants (Fig.4). The Hm (heterosis from mid-parent value) and Hh (heterosis from high-parent value) on secondary root number per plant, diameter of secondary root, root dry weight per cm3 soil, TTC reductive activities in root, total P content in plant and APase activity in flag leaves were almost all positive values(Table 1, 2). The Hm and Hh of grain yield per plant in three hybrid F1s were 31.7%–32.8% and 18.5%–29.6%, respectively（Table 1）.Making the hybrid combinations from the parents with high acquisition efficiency and variety with high utilization efficiency of P, and fully utilizing the heterosis of F1 on acquisition and utilization of P, will possibly have important roles to improve the P nutrition of wheat under P-deficient condition.
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