优质稻品种硒镉富集特性研究初报

Initial Study on Selenium and Cadmium Enrichment Characteristics of High Quality Rice Varieties

摘要: 为筛选适合株洲市种植的优质、富硒、低镉的优质稻品种，引进15个优质稻品种进行随机区组试验，在灌浆初期施用生物纳米硒肥1次，硒肥用量(以Se计) 1.25 g/667m²，测定精米镉、总硒、有机硒含量。结果表明：1) 在重度镉污染土壤条件下(1.17 mg/kg)，15个优质稻品种对镉的吸收积累能力存在一定的差异，但未达到显著水平(P = 0.05)；其中，精米镉含量最低的是拾两优1817，说明该品种具有低镉积累特性。与不施硒肥相比，施用硒肥品种的精米镉含量平均降低3.05%，降镉效果不明显。2) 15个优质稻品种籽粒硒富集能力存在极显著差异(P = 0.01)，精米硒含量品种间变幅在18.3~121.6 μg/100g，平均为67.5 μg/100g，说明通过施用含量硒叶面肥，完全可以在低硒或缺硒区生产出高含量的富硒大米。其中：玉针香、泰丰优农39、泰优农39、巴斯马蒂等品种的硒富集能力较强，在富硒大米生产中具有较好的优势。3) 15个优质稻品种精米的有机硒占比(%)有极显著差异(P = 0.01)，品种间变幅在76%~100%，平均为92%，其中：香优52、悦两优美香新占、美香占2号、农香42的有机硒占比达到99%，说明这些品种的硒生物转化率高。4) 以精米总硒含量或富硒效率(权重系数0.4)和有机硒占比(权重系数0.6)为指标进行灰色关联度分析表明，15个优质稻品种中，富硒综合性状优良的常规稻品种是玉针香和巴斯马蒂、三系杂交稻品种是泰优农39、两系杂交稻品种是泰丰优农39和又香优浓39。玉针香和巴斯马蒂为1等优质米，香味浓郁，食味好；且垩白粒率和垩白度低，透明度1级，外观品质高；667 m²产量400 kg左右，又符合当地气候生产条件对品种的特征要求，在高档富硒香米开发中具有良好的推广应用前景。

Abstract: In order to select high-quality rice varieties with high quality, low cadmium and rich selenium suitable for planting in Zhuzhou, 15 high-quality rice varieties were introduced to carry out a randomized block test. At the early stage of grain filling, biological nano selenium fertilizer was applied once, and the amount of selenium fertilizer (calculated as Se) was 1.25 g/667m². The contents of cadmium, total selenium and organic selenium in milled rice were determined. The results showed that: 1) under the condition of heavy cadmium pollution (1.17 mg/kg), there was a certain difference in the ability of cadmium absorption and accumulation among 15 high-quality rice varieties, but it did not reach a significant level (p = 0.05); Among them, the lowest cadmium content in milled rice is shiliangyou 1817, which indicates that this variety has the characteristics of low cadmium accumulation. Compared with no selenium fertilizer, the content of cadmium in milled rice with selenium fertilizer decreased by an average of 3.05%, and the effect of reducing cadmium was not obvious. 2) There was a very significant difference in grain selenium enrichment among 15 high-quality rice varieties (p = 0.01), and the selenium content in milled rice varied from 18.3 to 121.6 μG/100g, average 67.5 μG/100g, indicating that high selenium rich rice can be produced in low selenium or selenium deficient areas by applying selenium rich leaf fertilizer. Among them, Yu-zhen-xiang, Tai-feng-you-nong 39, Tai-you-nong 39, Basmati and other varieties have strong se-lenium enrichment ability, and have good advantages in the production of selenium rich rice. 3) The percentage of organic selenium in milled rice of 15 high-quality rice varieties was significantly different (p = 0.01), with a range of 76%~100% among varieties, with an average of 92%. Among them, the percentage of organic selenium in Xiang-you 52, Yue-liang-mei-mei-xiang-xin, Mei-xiang-zhan 2 and Nong-xiang 42 reached 99%, indicating that these varieties had a high selenium biological conversion rate. 4) Taking the total selenium content or selenium enrichment efficiency of milled rice (weight coefficient 0.4) and the proportion of organic selenium (weight coefficient 0.6) as indicators, the grey correlation analysis showed that among the 15 high-quality rice varieties, the conventional rice varieties with excellent selenium rich comprehensive characters were Yu-zhen-xiang and Basmati, the three-line hybrid rice variety was Tai-you-nong 39, and the two-line hybrid rice varieties were Tai-feng-you-nong 39 and You-xiang you-nong 39. Jade needle fragrance and basmati are first-class high-quality rice, with rich flavor and good taste; the chalky grain rate and chalkiness degree were low, the transparency was grade 1, and the appearance quality was high; the output of 667 m² is about 400 kg, which also meets the requirements of local climatic production conditions for varieties. It has a good prospect of popularization and application in the development of high-grade selenium rich fragrant rice.