不同pH低磷土壤上水稻磷营养特性研究

通过盆栽试验，研究了不同磷效率水稻在不同pH土壤和不同磷处理水平下的磷营养特性。结果表明，低磷条件下，分蘖期耐低磷基因型850、1574和1079的磷吸收效率最高，孕穗期3个耐低磷品种磷吸收量和利用效率均较高；到成熟期1574品种的相对磷吸收量最高，达到65%，而相对磷利用效率则以1574和850品种最高。不同pH土壤上，分蘖期，各水稻品种在碱性土壤上磷吸收量和利用效率最低，相对磷吸收量和相对磷利用效率却最高；耐低磷基因型850、1574和1079的磷吸收量高于鄂晚13和敏感基因型99012。在孕穗期，各水稻品种在碱性土壤上的磷吸收量高于其它两种土壤，但相对磷利用效率却最低；耐低磷基因型850和1574在3种土壤上磷吸收量均最高，成熟期各水稻品种磷利用效率则明显高于孕穗期。可见，不同耐低磷基因型在不同pH土壤上表现出的磷营养特性不同，在耐低磷品种的筛选过程中应该考虑土壤pH因素，生产中应根据不同土壤酸度类型选择合适的品种。

Phosphorous nutritional characteristics of rice in P-deficient soils with different pH values

A pot experiment was conducted to study the P-nutritional characteristics of different P-efficiency rice varieties in P-deficient soils with different pH values. The results indicated that, under low-P stress three low-P tolerant rice 850, 1574 and 1079 had the highest P uptake efficiency at tillering stage. P uptake and P use efficiency of the three low-P tolerant rice were higher than others at booting stage. At maturity stage, the relative P uptake of 1574 reached 65% and was the highest, 1574 and 850 had the highest relative P-use efficiency than others. With different pH values, at tillering stage, the P uptake and P-use efficiency on alkaline soil were the lowest, but the relative P uptake and P-use efficiency on alkaline soil was the highest, and the P uptake of 850, 1574 and 1079 was higher than EW13 and 99012. At booting stage, the P uptake on alkaline soil was higher than the other soils, but the relative P-use efficiency was the lowest, and the P uptake of 850 and 1574 was the highest. The P-use efficiency at maturity stage was significantly higher than at booting stage. This indicated that P-nutritional characteristics of different P-efficiency rice on P-deficient soils with different pH values differed, and soil pH values should be considered in screening rice with different P-efficiencies. It is necessary to choose the right variety for soils with different pH values.