Abstract: The activities of acid phosphatase (APase) in roots of hybrid rice and its parents at the tillering, booting and filling stages were studied with 7 rice parents and their combinations as materials in a solution culture experiment with different phosphorus levels to provide a foundation for screening high phosphorusefficient hybrid rice. The activities of APase in roots differed under different P levels among maintainer lines. Under low P level, the activity of APase in roots of Ⅱ32B (Pinefficient type) was not significantly higher than that of the control(suitable P level) at the tillering stage. The tolerance of D62B and D83B (Pefficient type) to low P stress was enhanced notably with increased activity of APase in roots. Meanwhile, there existed the differences in APase activities in roots of the restorer lines. Compared with the control, the activity of APase in roots of R892 and R527 (Pefficient type) increased significantly at the tillering and booting stages under low P levels. Whereas, the activities of APase in roots of R549 and R781(Pinefficient type) increased significantly only at the tillering stage. The increasing extents of APase activity in roots of the hybrid rice combination derived from different parents were also different. In the three periods, the differences in APase activity in roots of Ⅱyou 549(Pinefficient type) under low P level and the control were not notable, but the APase activity in roots of D83A/R527(Pefficient type) under low P level increased significantly compared to the check. The increasing extent of APase activity in roots of Ⅱyou 549 derived from Ⅱ32B and R549 was not significant at all the stages. The APase activity in roots of D83A/R527 from D83B and R527 increased markedly under low P level. And the increasing extents of APase activity in roots of Ⅱyou 892 (Ⅱ32B×R892) and D62A/R781 (D62B×R781) were between Ⅱyou 549 and D83A/R527 under low P level.

Key words: phosphorus stress, hybrid rice, acid phosphatase activity

摘要： 为了解优良亲本和杂交组合的磷营养遗传特性，以7份亲本及其4个组合为材料，采用水培试验研究了不同磷水平对水稻亲本及其杂交组合根系酸性磷酸酶（APase）活性的影响。在低磷条件下，磷低效型保持系材料Ⅱ32B的APase活性较对照增加不显著，而磷高效型保持系材料D62B和D83B则通过显著提高根系APase活性增强了对磷胁迫环境的适应性。磷高效型恢复系材料R892和R527在分蘖期和孕穗期的APase活性均较对照显著提高，而磷低效型恢复系材料R549和R781除在分蘖期APase活性增加明显外，在孕穗期和灌浆期APase活性与对照差异不显著。不同亲本配制的杂交稻在低磷水平下，根系APase活性增加的幅度有所不同。磷低效型杂交组合Ⅱ优549分蘖期、孕穗期和灌浆期根系的APase活性在不同供磷水平下差异不显著；磷高效型杂交组合D83A/R527在低磷水平下3个时期APase活性均明显提高。由磷低效型保持系材料Ⅱ32B与磷低效型恢复系材料R549配制的Ⅱ优549，根系APase活性受低磷胁迫增幅不大；磷高效型保持系材料D83B与磷高效型恢复系材料R527配制的D83A/R527， 根系APase活性在低磷水平下上升显著；磷低效型保持系材料Ⅱ32B与磷高效型恢复系材料R892配制的Ⅱ优892，以及磷高效型保持系材料D62B与磷低效型恢复系材料R781配制的D62A/R781，受低磷胁迫时根系APase活性上升幅度介于磷低效组合Ⅱ优549和磷高效组合D83A/R527之间。

关键词: 低磷胁迫, 杂交稻, 酸性磷酸酶活性