Contrasting Response of Nutrient Acquisition Traits in Wheat Grown on Bisphenol A-Contaminated Soils

Abstract

Repeated application of organic fertiliser has unintentionally let to the introduction into surface water and soils of many phytotoxic substances that compromise agricultural production and threaten environmental quality. Recent studies using hydroponic systems have reported that bisphenol A (BPA) affects essential mineral elements contents and root absorptive function, thereby impacting nutrient content in plant. However, in soils, plants develop specific traits related to nutrient acquisition strategies. In order to ensure optimised supply of nutrients, understanding the response of these traits under BPA stress is thus essential. Here, we therefore, investigated how leaf nutrient contents (P, Ca and K), root morphology, P-mobilising exudates and rhizospheric microbiota biomass respond to BPA soil contamination using wheat (Triticum aestivum) as plant model. After 7 weeks, root and leaf traits were not markedly affected by the exposure to BPA at low and high concentrations (0.1 and 1000 mg kg−1 soil). Significant change on average root diameter and aerial biomass were only observed at the highest dose. BPA contamination had no influence on nutrients acquisition traits and root-associated microbiota. Specific root length, carboxylates exudation and P, Ca and K concentrations in leafs were similar irrespective of the treatments. In addition, total microbial biomass, bacteria and fungi abundance measured through phospholipid fatty acid analysis did not differ among controls and contaminated soils. In summary, this experiment suggests a limited influence of BPA contaminated soils on traits involved in nutrient acquisition in wheat.