Guangdong Provincial Key Laboratory of Plant Molecular Breeding, Guangdong Subcenter of National Center for Soybean Improvement, College of Agriculture, South China Agricultural University, Guangzhou, 510642, Guangdong, China.
Environ Sci Pollut Res Int. 2016 Jan;23(2):1860-72. doi: 10.1007/s11356-015-5424-4. Epub 2015 Sep 24.
To examine the differences in root morphological responses of soybean cultivars with different cadmium (Cd) tolerance and accumulation to Cd stress, the biomass, Cd concentration, and root morphological features of five soybean cultivars were determined under 0, 9, 23, 45, and 90 μM Cd stress via hydroponic experiments. Significantly genotypic differences in Cd tolerance and Cd concentration were observed between five soybean cultivars at four Cd levels. For Cd tolerance, HX3 showed a strong Cd tolerance with tolerance indexes of shoot biomass at 92.49, 76.44, 60.21, and 46.45% after 18 days at four Cd levels, and others had similar weak tolerance at young seedling. For Cd accumulation, Cd concentration in roots showed far higher than that in shoots. The different accumulation features in roots and shoots among five cultivars were found at four Cd levels. Comparing with the control, the total root length (RL), root surface area (SA), and root volume (RV) of all cultivars were decreased significantly at four Cd levels. Tolerant cultivar HX3 had the largest root system and sensitive cultivar BX10 had the smallest root system at young seedling stage. Correlation analysis indicated that RL, SA, and RV were positively correlated with root biomass and shoot biomass under 9 and 23 μM Cd treatments, but root average diameter (RD) was negatively correlated with shoot biomass and root biomass only under 9 μM Cd treatments, while RL and SA were negatively correlated with root Cd concentration under 23 and 45 μM Cd treatments. The results suggested that root morphological traits were closely related to Cd tolerance at young seedlings under Cd treatments.
为了研究不同耐镉和积累镉能力的大豆品种在镉胁迫下根系形态响应的差异，通过水培实验，在 0、9、23、45 和 90 μM Cd 胁迫下，测定了 5 个大豆品种的生物量、Cd 浓度和根系形态特征。在 4 个 Cd 水平下，5 个大豆品种对 Cd 的耐受力和 Cd 浓度存在显著的基因型差异。就 Cd 耐受力而言，HX3 在 4 个 Cd 水平下的地上部生物量耐性指数分别为 92.49%、76.44%、60.21%和 46.45%，表现出较强的 Cd 耐性，而其他品种在幼苗期表现出相似的弱耐性。就 Cd 积累而言，根中的 Cd 浓度远高于地上部。在 4 个 Cd 水平下，5 个品种的根和地上部积累特征不同。与对照相比，所有品种在 4 个 Cd 水平下的总根长（RL）、根表面积（SA）和根体积（RV）均显著下降。在幼苗期，耐镉品种 HX3 的根系最大，而敏感品种 BX10 的根系最小。相关性分析表明，在 9 和 23 μM Cd 处理下，RL、SA 和 RV 与根生物量和地上部生物量呈正相关，但在 9 μM Cd 处理下，RD 与地上部生物量和根生物量呈负相关，而在 23 和 45 μM Cd 处理下，RL 和 SA 与根 Cd 浓度呈负相关。结果表明，在 Cd 处理下，幼苗期根系形态特征与 Cd 耐性密切相关。
