PDF(Pubmed)
Abstract：
Iron (Fe) toxicity in plant species depends on the availability of Fe in the soil, uptake ability by the root system, and translocation rate to other parts of the plant. The aim of this study was to assess Fe uptake by root tissues of Catharanthus roseus, translocation rate to leaf tissues, and the impairment of plant physio-morphological characteristics. Fe uptake by the roots (~ 700 µg g-1 DW) of C. roseus was observed during the early exposure period (1 week), and translocation factor from root to shoot was fluctuated as an independent strategy. A high level of Fe content in the root tissues significantly inhibited root length and root dry weight. Under acidic pH condition, an enrichment of Fe in the shoots (~ 400 µg g-1 DW) led to increase in leaf temperature (> 2.5 °C compared to control) and crop stress index (> 0.6), resulting in stomatal closure, subsequently decreasing CO2 assimilation rate and H2O transpiration rate. An increment of CSI in Fe-stressed plants was negatively related to stomatal conductance, indicating stomatal closure with an increase in Fe in the leaf tissues. High Fe levels in the leaf tissues directly induced toxic symptoms including leaf bronzing, leaf spotting, leaf necrosis, leaf chlorosis, and leaf senescence in C. roseus plants. In summary, C. roseus was identified as a good candidate plant for Fe phytoextraction, depending on Fe bioaccumulation, therefore 50 mM Fe treatment was designated as an excess Fe to cause the growth inhibition, especially in the prolonged Fe incubation periods.
UNASSIGNED:
UNASSIGNED: The online version contains supplementary material available at 10.1007/s12298-023-01379-5.
UNASSIGNED:
UNASSIGNED: The online version contains supplementary material available at 10.1007/s12298-023-01379-5.
摘要：
植物中的铁（Fe）毒性取决于土壤中Fe的有效性，根系的吸收能力，以及转移到工厂其他部分的速率。这项研究的目的是评估长春花根组织对铁的吸收，向叶片组织的转运率，以及植物生理形态特征的损害。在早期暴露期（1周）观察到玫瑰梭菌根（约700µgg-1DW）的铁吸收，从根到芽的易位因子作为独立策略波动。根组织中高水平的Fe含量显着抑制根长和根干重。在酸性pH条件下，芽中Fe的富集（〜400µgg-1DW）导致叶片温度升高（与对照相比>2.5°C）和作物胁迫指数（>0.6），导致气孔关闭，随后降低CO2同化率和H2O蒸腾速率。铁胁迫植物中CSI的增加与气孔导度呈负相关，表明气孔关闭，叶片组织中Fe的增加。叶片组织中的高Fe水平直接引起毒性症状，包括叶片古铜色，叶子斑点,叶片坏死,叶黄化,和C.roseus植物的叶片衰老。总之,C.roseus被确定为铁植物提取的良好候选植物，取决于铁的生物积累，因此，50mMFe处理被指定为过量的Fe以引起生长抑制，特别是在长时间的铁潜伏期。
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■在线版本包含补充材料，可在10.1007/s12298-023-01379-5获得。
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■在线版本包含补充材料，可在10.1007/s12298-023-01379-5获得。
