In rice systems under continuous flooding(CF)irrigation,rice grains with high arsenic(As)concentration can be produced.In Argentina,these areas are located in the south of Corrientes Province and the north of Entre R&...In rice systems under continuous flooding(CF)irrigation,rice grains with high arsenic(As)concentration can be produced.In Argentina,these areas are located in the south of Corrientes Province and the north of Entre Ríos Province.The combination of agronomic management,genetic variability of rice varieties,and the characteristics of soil and irrigation water determines the concentration and proportion of grain As species.In this study,we evaluated two factors affecting grain As accumulation:irrigation management,CF and interrupted flooding(IF),and rice variety,rice with medium,long,and double long/wide grains.The experiments were conducted during four cropping cycles(2015–2016,2016–2017,2017–2018,and 2020–2021)on a farm in the north of Entre Ríos Province.Total As concentration in husked grains showed a wide range and was mostly above 0.30 mg kg^(-1),even after the polishing process.Fortunately,organic As was the predominant species.In polished rice,inorganic As concentration ranged between 0.02 and 0.28 mg kg^(-1).Significant differences were observed in grain As concentration between four rice varieties,with the highest inorganic and total As concentrations in grains of the medium-grain variety.The interaction of rice variety by irrigation management did not affect grain yield,but significantly reduced total As concentration in grains.Soil drainage under IF explained 43%–46%of the reduction of total As concentration in grains.The management practices of irrigation and rice variety had slight effects on inorganic As concentration in grains.In conclusion,a single soil drying period combined with proper rice varieties can be an effective management practice for mitigating As accumulation in rice grains.展开更多
基金the National Agency for the Promotion of Research,Technological Development and Innovation(Argentina)the National University of Entre Ríos(Argentina)+1 种基金the PROARROZ Foundation(Argentina)the company EBRO(Argentina)for the financial support of this research。
文摘In rice systems under continuous flooding(CF)irrigation,rice grains with high arsenic(As)concentration can be produced.In Argentina,these areas are located in the south of Corrientes Province and the north of Entre Ríos Province.The combination of agronomic management,genetic variability of rice varieties,and the characteristics of soil and irrigation water determines the concentration and proportion of grain As species.In this study,we evaluated two factors affecting grain As accumulation:irrigation management,CF and interrupted flooding(IF),and rice variety,rice with medium,long,and double long/wide grains.The experiments were conducted during four cropping cycles(2015–2016,2016–2017,2017–2018,and 2020–2021)on a farm in the north of Entre Ríos Province.Total As concentration in husked grains showed a wide range and was mostly above 0.30 mg kg^(-1),even after the polishing process.Fortunately,organic As was the predominant species.In polished rice,inorganic As concentration ranged between 0.02 and 0.28 mg kg^(-1).Significant differences were observed in grain As concentration between four rice varieties,with the highest inorganic and total As concentrations in grains of the medium-grain variety.The interaction of rice variety by irrigation management did not affect grain yield,but significantly reduced total As concentration in grains.Soil drainage under IF explained 43%–46%of the reduction of total As concentration in grains.The management practices of irrigation and rice variety had slight effects on inorganic As concentration in grains.In conclusion,a single soil drying period combined with proper rice varieties can be an effective management practice for mitigating As accumulation in rice grains.
