Relationship between silica and silicophytoliths with heavy metals in a wheat (Triticum aestivum) planted with silicon fertilization

摘要

Abstract Plants can absorb Si from the soil solution to produce biomineralizations, known as silicophytoliths (SiP), which could help to mitigate abiotic stresses, including improved tolerance to heavy metals (HM). The Argentinian Pampean plain region is highly fertile and intensive agricultural activities are carried out. This work evaluates the effect of Si fertilization on the HM content of soils and plants in an agricultural area cultivated with wheat (Triticum aestivum) in the southeastern region of the Pampean plains. The HM content was analyzed in soil and plant organs with ICP-OES, while SiP content was measured by calcination; finally, SEM and EDS analyses were performed. In general, no statistically significant effect after the application of silicon fertilizers was detected, but an inverse relation was observed between the Si and HM contents in soil and the aboveground organs of the crop. Within the plant organs, a strong relationship between the distribution of HM and SiP contents was found and this relation could also be seen with SEM and EDS analysis done. This is the first work that addresses, within the agroecosystems of the Pampean plains, Si and HM contents in wheat crops and provides basic data to evaluate possible studies related to their effects under different stress conditions. Although further studies at the cellular level are needed to elucidate some hypotheses, the results obtained suggest that it could be useful to apply Si fertilization as an environmentally friendly strategy.