不同甘薯品种对镉的积累与转运特性研究

目的]旨在为甘薯在中轻度稻田镉污染地区种植结构调整提供技术支撑。方法]以20个甘薯品种作试验材料，采用旱地小区试验，研究中轻度稻田镉污染区甘薯的生长发育及其积累和转运Cd的差异。结果]供试甘薯品种的蔓长、茎粗、生物量、产量以及茎叶、块根积累和转运镉的能力存在品种差异。有3个品种的茎叶镉含量超过无公害蔬菜质量标准(<0．05 mg.kg-1),所有品种茎叶和块根的Cd含量均符合国家食品中污染物限值标准 ( <0．1 mg.kg-1 )。茎叶和块根富集系数范围分别为0．225～1.222、0．022～0.160,转运系数范围为0.067～0.511,说明甘薯对土壤Cd仍有一定的吸收能力,但由茎叶向块根的转运能力较弱。结论]‘QS816’、‘湘薯20’、‘湘108’、‘广87’可作为中轻度稻田镉污染区种植甘薯的优先选择品种，在种植结构调整方面具有潜在的应用价值。

Cadmium Accumulation and Translocation in Sweet Potato Cultivars

The paper aims to provide technical support for planting structure adjustment of sweet potato in mild paddy cadmium (Cd) pollution areas. 20 sweet potato cultivars were used as the materials. The arid land plot was designated and conducted to study the growth and development of sweet potato in the mild paddy cadmium (Cd) pollution area, and the difference of Cd accumulation and translocation. The results showed that there were differences in vine length, stem diameter, biomass, yield as well as Cd accumulation and translocation ability of stem & leaf and root among the 20 sweet potato cultivars. The Cd contents in stem & leaf of 3 cultivars exceeded the pollution-free vegetable quality standard (<0.05 mg/kg). The Cd contents in stem & leaf and root of all the cultivars conformed to the national standard of the food pollutant limit (<0.1 mg/kg). The range of the Cd accumulation coefficient in stem & leaf and root was 0.225- 1.222 and 0.022- 0.160, respectively. And the transferring coefficients range was 0.067-0.511. It indicates that sweet potato has certain absorptive capacity to soil Cd, but the translocation ability of Cd from stem & leaf to root is weak.‘QS816’, Xiang 20’,‘Xiang 108’and‘G87’can be used as the excellent cultivars in the mild paddy cadmium pollution areas, and have potential application value in adjusting the planting structure.