镉胁迫对甘蓝型油菜苗期生长及镉积累的影响

Effects of Cadmium Stress on Growth and Cadmium Accumulation Characteristics of Brassica napus L. Seedlings

镉(Cd)是生物毒性强的重金属元素,易在土壤-动植物-人体间富集转移,最终危害人体健康。为了筛选富集/耐镉性强的油菜品种,以6个油菜品种为材料,通过研究镉胁迫对幼苗生长、镉积累、谷胱甘肽(GSH)含量等的影响,明确不同品种镉富集能力的差异。结果表明,镉胁迫对不同油菜品种幼苗叶干重均有抑制作用,对美油88的抑制作用最大,对南油868的抑制作用最小。镉胁迫下不同油菜品种幼苗根干重存在差异,南油868最大。镉胁迫对早熟100天、丰油9号幼苗根干重抑制作用最大,而对美油88抑制作用最小。镉胁迫对不同品种幼苗根冠比均有所提高,其中美油88提高幅度最大,而南油868提高幅度最小。不同品种幼苗生物量存在差异,在正常及镉胁迫条件下,南油868的生物量均显著高于其余品种。镉胁迫对美油88幼苗生物量抑制作用最大,对南油868抑制作用最小。不同品种,镉含量存在显著差异,南油868具有高富集特性,美油88具有低富集特性。外源镉显著增加了不同油菜品种幼苗叶片谷胱甘肽含量,美油88的增幅最大,其次为南油868。最终,筛选出镉富集量最小的油菜品种美油88,镉富集量最大的油菜品种南油868,可进一步培育低镉油菜,或进行镉污染耕地修复研究。

Cadmium(Cd) is a heavy metal element with strong biotoxin, which is easy to be enriched and transferred between soil, animals and plants, and human body, and ultimately endangers human health. In order to screen Brassica napus L. varieties with high concentration/cadmium(Cd) tolerance, six B. napus varieties were selected for studying the effects of cadmium stress on seedling growth, Cd accumulation, glutathione(GSH) content etc. The results showed that Cd stress inhibited leaf dry weight of different varieties seedlings, with the largest inhibition on Meiyou 88 and the smallest on Nanyou 868. There was certain difference in the seedling root dry weight of different rape varieties. Under stress conditions, Nanyou 868 had the largest root dry weight. Cadmium stress had the largest inhibition on root weight of Zaoshu 100 Days and Fengyou 9 seedlings, and the smallest inhibition on Meiyou 88. The Root-shoot ratio of the six tested varieties increased under Cd stress, with the highest increase of Meiyou 88 and the smallest increase of Nanyou 868. There was certain difference in the biomass of different varieties. Under normal and stress conditions, Nanyou 868 was significantly higher than the others. Cd stress had the greatest inhibitory effect on the biomass of Meiyou 88 seedlings and the least on Nanyou 868 seedlings. There were significant differences in heavy metal contents among different varieties. Meiyou 88 had low Cd concentration, Nanyou 868 had high Cd concentration. But the results showed that glutathione content of different varieties significantly increased under the Cd stress, with the highest increase rate of Meiyou 88, followed by Nanyou 868. This study provides guidance for food safety or repairing Cd contaminated soil in B. napus L.