[Objective] The objective of this study was to clarify the effects of P additions and P-efficiency on grain yield, biomass and quality of rice in As-contaminated soil, and discuss agronomic measures for mitigation of As accumulation in rice. [Method] Low-P tolerant rice cultivars 99011 with high P-absorption-efficiency and 580 with high P-use-efficiency, and low-P sensitive rice cultivar 99056 were used in a pot experiment to study the effects of P additions on grain yield, biomass and P and As concentration in the straw, husk and brown rice in moderate and high As-contaminated soils. [Result] Compared to no As-contamination treatment, 50 mgkg1 of As increased the biomass of three supplied rice slightly, but decreased grain yield significantly. Both the biomass and the grain yield increased significantly with the increase of P supply As at 100 mg kg"' decreased both the biomass and the grain yield significantly. The biomass increased obviously with increasing P supply, however, the grain yield was the highest at 30 mgkg'1 of P level but the lowest (0) at 150 mgkg"' of P level. Under As-contaminated conditions, the Asconcentration in different organs were straw ?husk ?brown rice, and they increased with increasing P and/or As additions. In As stress or P and As double stress soils, the grain yield, biomass and the P concentration in straw, husk and brown rice were all 99011 > 580>99056, with remarkable difference among three rice cultivars, moreover, the difference among the three rice cultivars increased with the reduce of P supply and the increase of As supply. The As concentrations in straw, husk and brown rice were all 99056>580 >99011, with prominent difference among the three rice cultivars, moreover, the difference among the three rice cultivars increased with the increase of P and/or As supply. Under the conditions of As addition was ^50 mgkg'and P supply was <30 mgkg', low-P tolerant rice cultivar 99011 could get considerable grain yield and the As concentration in brown rice was lower than the national food safety standard. [Conclusion] Under As-contaminated conditions, the grain yield and the quality of rice are closely related to the P additions and the uptake ability of rice to low concentration of P. Using rice cultivars with high P-absorption-efficiency and reducing P fertilizer input properly are promising rotes for getting considerable production with reduced grain As in moderatly and slightly As-contaminated soil.%[目的]阐明磷肥用量以及水稻磷营养特性对砷污染水稻产量、生物量及其安全性的影响,探讨降低水稻砷污染的农艺措施.[方法]以2个耐低磷(磷高效吸收型品种99011和磷高效利用型品种580)和1个低磷敏感型水稻( 99056)为材料,通过土培试验研究不同磷用量对中、高度砷污染土壤上水稻产量、生物量以及秸秆、颖壳和稻米P、As含量的影响.[结果]与无砷处理相比,50 mg·kg-1的砷略微增加水稻的生物量,但降低水稻产量,增施磷肥显著提高生物量和产量；100 mg·kg-1的砷显著降低水稻生物量和产量,增施磷肥显著提高生物量,但产量在磷用量为30 mg·kg-1时最高,磷用量为150 mg·kg-1时最低(为0).砷污染土壤上,水稻不同部位As含量为秸秆＞＞颖壳＞＞糙米,且As含量随磷用量或砷浓度的增加而增加.在砷胁迫或者磷、砷双重胁迫下,同一处理的水稻产量、生物量以及秸秆、颖壳和糙米P含量均为99011＞ 580＞ 99056,3个品种之间差异显著,且磷用量越少、砷浓度越高,品种之间差异越大；秸秆、颖壳和糙米As含量为99056＞ 580＞ 99011,3个品种之间差异显著,且磷用量和(或)砷浓度越高,品种之间差异越大.在砷浓度≤50 mg·kg-1和磷用量≤ 30 mg·kg-1时,磷高效吸收型品种99011能够获得较高的产量,且稻米As含量低于国家食品安全标准.[结论]砷胁迫下,水稻产量及其As含量与品种磷营养特性以及施肥量密切相关.在中、轻度砷污染土壤上,可以通过选用磷高效吸收型水稻品种,并根据土壤磷丰缺程度适当减少磷肥用量等措施来保证水稻数量和质量安全.
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