纳米硅藻土的不同应用方式对水稻生长及其抑制吸收镉的影响

Effects of Different Application Methods of Nano-Diatomite on Rice Growth and Inhibition of Cadmium Uptake

摘要: 目的：通过盆栽试验探究复混肥中添加不同量纳米硅对水稻生长的影响，同时研究叶面喷施纳米叶面阻隔水稻阻隔重金属镉的效果。基于此，考察综合利用纳米硅的两种不同施用方法对水稻生长及阻隔镉吸收的效果。方法：利用长沙重金属镉污染土壤种植水稻，在水稻分蘖期、抽穗前期喷施纳米硅叶面阻隔剂。叶面阻隔剂浓度为0.1 g/L、0.5 g/L和0.8 g/L，考察水稻籽粒中的重金属镉的含量。复混肥中添加质量比为1%的非纳米硅藻土和纳米硅藻土。与不添加硅藻土的普通复混肥对比，利用普通种植土种植水稻，考察水稻生长性状。在长沙重金属镉污染的农田实施试验，综合考察叶面喷施纳米硅藻土和添加纳米硅藻土的复混肥对水稻产量和稻米中镉含量的影响。结果：结果表明，添加纳米硅藻土的复混肥能提高水稻植株干重，在纳米硅藻土添加1%的情况下，氮磷钾的利用率提供了53.80%，植株总干重提高50.04%，根系干重提高185%。喷施两次纳米硅藻土后，水稻中镉含量显著(P < 0.05)降低，与对照相比，浓度为0.1 g/L、0.5 g/L和0.8 g/L纳米硅藻土喷施后各处理茎叶和籽粒中镉含量分别降低了15.84%、6.93%、3.96%和53.85%、23.80%、38.47%。大田实验的结果表明，同时施用叶面阻隔剂和含有纳米硅的复合肥与当地施用普通的复合肥相比较，水稻精米中的镉含量降低了58.8%，产量增加27%。结论：从研究结果可以看出，叶面喷施纳米硅藻土的同时施用含有纳米硅藻土的复混肥能增加水稻产量、阻隔水稻对重金属镉的吸收，提高稻米品质。

Abstract: Objective: The pot experiment was conducted to investigate the effect of adding different amounts of nano-diatomite on the growth of rice in compound fertilizer and at the same time, the effect of foliar spraying of nano leaf barrier on the removal of heavy metal cadmium was also studied. Based on this, the effects of two different application methods of nano silicon on rice growth and cadmium absorption were investigated. Methods: Changsha heavy metal cadmium contaminated soil is used to plant rice, and nano silicon leaf barrier agent was sprayed at tillering stage and heading stage. The concentrations of heavy metal cadmium in rice grain were determined at 0.1 g/L, 0.5 g/L and 0.8 g/L. Compound fertilizer was added with non-nano diatomite and nano diatomite with mass ra-tio of 1%. Rice was grown with common soil as the comparison of soil with ordinary compound fertilizer without diatomite and then the growth characteristics of rice between the two were investigated. The effects of spraying nano diatomite and adding nano diatomite on the yield of rice and the content of cadmium in rice were investigated in the field of heavy metal cadmium pollution in Changsha. Results: The results showed that the dry weight of rice plant could be improved by adding nano diatomite compound fertilizer. Under the condition of adding 1% nano diatomite, the utilization rate of N, P and K was 53.80%, the total dry weight of plant increased by 50.04%, and the dry weight of root increased by 185%. After the spraying of two nanoscale diatomite, the content of cadmium in rice decreased significantly (P < 0.05). Compared with the ordinary experiment, the concentration of cadmium in the leaves and grains of 0.1 g/L, 0.5 g/L and 0.8 g/L nano diatomite decreased by 19.85%, 8.09%, 4.89% and 109.07%, 32.85% and 61.71% respectively. The results of the field experiment showed that the content of cadmium in rice was reduced by 58.8% and the yield increased by 27%, compared with the compound fertilizer containing the foliar barrier and the nano silicon. Conclusion: From the results, it can be seen that the application of nano silicon in the application of the compound fertilizer with nano silicon can increase the rice yield, block the absorption of heavy metal cadmium and improve the quality of rice.