Abstract: Selenium contents of 52 samples of polished rice from various rice varieties in Jiangsu Province and 30 samples of polished rice from different regions of China were determined by hydride generation atomic fluorescence spectrometry, and the effect of foliar application of selenium enriched fertilizer on content and constitution of selenium in rice were also studied. Results showed that the mean selenium contents of rice in Jiangsu and some regions of China were 0.025±0.011 mg/kg (ranged from 0.011 mg/kg to 0.055 mg/kg) and 0.035±0.009 mg/kg (ranged from 0.015 mg/kg to 0.056 mg/kg) respectively. Rice in Enshi was found to have the highest rice selenium content at 0.262 mg/kg among all rice samples. Based on cereal food intake recommended by China Nutrition Society, the daily dietary selenium intake from rice for an adult in Jiangsu and others were estimated to be 10.5-17.5 μg and 7.5-12.5 μg respectively, which contributed a very low dietary selenium intake for inhabitants. Selenium contents of rice were significantly increased to 0.471-0.640 mg/kg by foliar application of selenium enriched bio fertilizer with selenite or selenate, and the portion of organo selenium were enhanced from 78.38% in regular rice to 87.11%-89.08% in selenium enriched rice. Selenium content and assimilation of rice could be promoted by selenium foliar application on rice. As rice is staple food in China, selenium enriched rice through bio enrichment with selenium would be a good selenium source for the population in selenium deficient regions.

Key words: rice, selenium content, chemical constitution, selenium fertilizer

摘要： 用原子荧光分光光度法测定了江苏省52个不同品种大米样品、全国部分省市30个大米样品以及两种用不同硒生物肥生产的富硒大米的含硒量，研究了生物硒肥对大米含硒量及硒形态的影响。结果表明，江苏省的大米含硒量为0.015～0.056 mg/kg，平均为0.035 mg/kg±0.009 mg/kg；全国部分地区的大米含硒量为0.011～0.055 mg/kg，平均为0.025 mg/kg±0.011 mg/kg，湖北恩施的大米含硒量达0.262 mg/kg。依据中国营养学会推荐的谷物食品摄入量，推算江苏省和其他地区居民从大米中摄入的硒分别为10.5～17.5 μg/(d·人)和7.5 ～12.5 μg/(d·人)。在水稻齐穗期喷施硒20 g/hm2，大米含硒量由普通大米的0.071 mg/kg分别提高到0.471 mg/kg和0.640 mg/kg，有机硒比例分别由普通大米的78.38％提高到87.11％和89.08％。外源硒能显著提高大米的含硒量和有机硒含量及比例。

关键词: 大米, 硒含量, 化学形态, 硒肥