水稻叶镉与米镉含量的相关性及叶面肥对镉的阻控研究

Relationship of Cadmium Content in Rice Leaves with Seeds and Resistance of Foliar Fertilizer to Cadmium

为了探究水稻叶中镉含量与糙米中镉含量的关系,以及施加不同叶面肥对水稻产量及稻米中镉含量的影响,在湖南省株洲县某镉污染区随机采集水稻样品进行分析,并在该地选择镉污染稻田开展4种不同叶面肥(Ca肥、Si肥、N肥和Fe肥)的阻控水稻富集镉的试验。结果表明:随机采集的水稻植株中镉含量的分布是根>茎>籽粒,叶中镉含量的分布是第一叶>第二叶>第三叶>第四叶及其他叶,水稻叶中镉含量与糙米中镉含量呈显著正相关,其中第一叶中镉含量与糙米中镉含量之间的相关性达到0.857 8。与对照相比,施加不同叶面肥后,水稻明显增产8.14%～27.27%,其中施加叶面Fe肥水稻增产效果最明显。在4种叶面肥的不同浓度处理下,降低糙米中镉含量效果顺序是低浓度>中浓度>高浓度,当叶面肥低浓度处理时,Si肥阻控稻米富集镉效果最佳,达到57.14%;其次是Ca肥和Fe肥,分别达38.78%和32.66%;N肥的降镉率为16.33%。

In order to study the relationship between Cd contents in rice leaves and Cd contents in brown rice as well as the effect of different foliar fertilizers on rice yield and Cd contents in brown rice.In this study,rice samples were randomly collected from Cdcontaminated area in Zhuzhou County,Hunan Province.Four different foliar fertilizers(Ca fertilizer,Si fertilizer,N fertilizer and Fe fertilizer)were employed to control Cd accumulation in rice.The results showed that the order of Cd contents in rice was following by root>stem>grain,and the distribution of Cd contents in different leaves followed the order of the first leaf>the second leaf>the third leaf>the fourth leaf and other leaves.Moreover,there was a significant positive correlation between Cd contents in rice leaves and Cd concentrations in brown rice.In particular,Cd contents in the first leaf prior to other leaves can promote Cd contents in brown rice in terms of correlation of 0.8578.Compared with the control,the yield of rice increased by 8.14%-27.27%after applying different foliar fertilizers,and the effect of applying foliar Fe fertilizer was the most obvious.The order of effect of reducing cadmium content in brown rice was low concentration>medium concentration>high concentration under four different concentrations of foliar fertilizer.When foliar fertilizer was low concentration,the effect of Si fertilizer on controlling cadmium concentration in rice was the best,reaching 57.14%.Ca fertilizer and low concentration Fe fertilizer were in next place,which reached 38.78%and 32.66%respectively.The cadmium reduction rate of N fertilizer was 16.33%.