土壤Cu含量对武香粳14号稻米品质的影响

在盆栽土培条件下,以武香粳14号为供试材料,研究土壤Cu含量(50-1 000mg/kg)对水稻糙米中蛋白质、Fe、Zn、M n、M g和Cu含量的影响以及Cu在籽粒不同部位中的分布。结果表明,随着土壤Cu含量的提高,糙米蛋白质含量极显著增加(r=0.88*-0.91**),而糙米中Fe、Zn、M n、M g的含量显著或极显著下降(r=-0.95**--0.58*),增加或下降的幅度因不同营养元素和不同土壤Cu处理而异;当土壤Cu含量小于200mg/kg时,糙米Cu含量随土壤Cu胁迫的加重而增加,土壤Cu含量大于200mg/kg时则相反,土壤Cu含量达200mg/kg时,糙米中Cu含量达到最大值(11.3mg/kg);Cu在籽粒不同部分的分布差异很大,从浓度分布看,米糠中Cu浓度大约是谷壳、精米的2倍,从积累量分布看,谷壳、米糠和精米中Cu积累量平均分别占籽粒总积累量的12%、24%和64%,即稻谷经精加工后,其Cu总量下降1/3左右。

Effects of Soil Cu Concentration on Grain Quality of Rice Cultivar Wuxiangjing 14

In order to investigate the effect of soil Cu stress(50～1000 mg.kg-1) on the concentrations of protein,Fe,Zn,Mn,Mg,Cu and the distribution of Cu in the different products of rice(Oryza sativa L.) grains processing,pot experiments are conducted using the japonica cultivar Wuxiangjing 14.Main results show that protein concentrations of brown rice increase with the increment of soil Cu levels(r=0.88*～0.91**),but Fe,Zn,Mn and Mg concentrations of brown rice generally decrease with soil Cu concentrations(r=-0.95**～-0.58*).The degrees of the increases and decreases differ with the elements and soil Cu levels.Cu concentrations in rice grain increase with soil Cu levels below 200 mg kg-1,but decrease with soil Cu levels above 200 mg kg-1,with peak Cu concentration at soil Cu level of 200 mg kg-1.Cu is not distributed evenly in different parts of grain structure.On the concentration distribution,it is about 2-fold in cortex(embryo) than in chaff and polished rice.With regard to Cu quantities accumulated in the products,about 64% of the total Cu in grain is accumulated in polished rice averagely,about 24% in cortex(embryo),and about 12% in chaff.So,about 1/3 of the Cu in grain is eliminated after grain processing(chaff,cortex and embryo are removed).