小白菜和空心菜对不同形态碘的吸收

Uptake of bok-choy and Ipomoea aquatica Forsk to iodine species

通过营养液培养试验研究了小白菜和空心菜对不同形态碘（I^-、IO3^-和CH2ICOO^-）的吸收特征。研究结果表明，低水平的外源碘能促进小白菜和空心菜的生长；在0～1．0mg／L（以I计算）的碘水平范围内，小白菜和空心菜对碘的吸收量随外源碘水平的提高而增加；对不同形态碘吸收量大小顺序为：CH2ICOO^-〉I^-〉IO3^-。小白菜和空心菜根部和地上部分中碘的含量之间呈显著相关性，其中小白菜根部和地上部分中碘的含量比约为2：1；空心菜根部和地上部分碘的含量比约为1：1，反映了不同蔬菜对碘吸收的差异性。

A hydroponic experiment was carried out to investigate the influence of iodine species： iodide （I^-）, iodate （IO3^-） and iodoacetic acid （CH2ICOO^-） on iodine uptake by leafy vegetables （Bok-choy and Ipomoea aquatica Forsk）. The results show that low level of iodine can efficiently promote the biomass of Bok-choy and Ipomoea aquatica Forsk. When iodine level in the nutrient solution from 0 to 1.0 mg/L, the iodic quantities uptaked by bok-choy and Ipomoea aquatica Forsk are enhanced with the iodine levels in nutrient solution increase. The rank of iodine species by Bok-choy and Ipomoea aquatica Forsk is CH2ICOO^- 〉 I^- 〉 IO3^- . There is a significant correlativity between the I contents in shoots and roots of bok-choy and Ipomoea aquatica Forsk. The ratios of I contents in roots to in shoots of bok-choy and Ipomoea aquatica Forsk are roughly 2：1 and 1 ： 1, respectively, which indicates the differences in iodine uptaked by plants.