| Abstract [eng] |
In view of the drastically increased concentration of heavy metals (HMs) in soil over the recent decades, pollution by HM is considered one of the most important environmental problems worldwide. Among all the HMs, Cd has the highest solubility in water, therefore, is one of the most mobile heavy metals in the environment and can be easily taken up by plants. Cd contamination of agricultural soils is, therefore, of particular concern because it reaches the food chain through regular use of Cd-containing phosphate fertilizers, posing a threat to human health. Since HMs are non-degradable and therefore persist for a long time after being introduced into the soil, the most suitable strategy to remediate Cd-contaminated soils is to remove Cd out of the soil. Phytoextraction is such a plant-based technique where plants are used to translocate Cd from soil to plant tissues, which has been considered as a secure, environmentally friendly, and cost-effective approach to remediate Cd-contaminated soils. Like other Brassica species, Brassica napus has many features, such as high biomass production, rapid growth rate and the ability to sequester Cd at a relatively high concentration without impairing its growth or development, that are suitable for the phytomanagement of Cd-contaminated soils. Besides, it is also an emerging biofuel crop that can be used to produce biofuel when grown in degraded soil. Moreover, recent studies have shown that, under warmer climate conditions, especially in conjunction with elevated CO2, B. napus highly increased their above-ground biomass production, indicating an even higher potential for phytoextraction purposes in the future climate. However, as the mobility of Cd in the soil is affected by many factors, its bioavailability may be also affected by climate change-related factors, such as elevated CO2 and temperature. In addition, reduced soil moisture as one of the most significant climate change-related factors also plays an important role in the soil environment and can negate all the advantages gained from the hotter climates. Therefore, the aim of this study was to investigate Cd phytoextraction efficiency by pot grown B. napus under drought conditions (5 vs. 30% of volumetric soil water content) in the current climate (21/14 ◦C and 400 µmol mol1 CO2) and future climate (25/18 ◦C and 800 µmol mol−1 CO2) conditions. For this, Cd accumulation in B. napus and their photosynthetic performance were evaluated. |
