Aluminum tolerance of Arabidopsis thaliana under hydroponic and soil culture conditions

Abstract

We compared the aluminum (A1) tolerance of three Arabidopsis thaliana ecotypes [Columbia (Col-O), Wassilewskija (Ws), and Landsberg (Ler)] and an AI-tolerant line (A1-t) selected from Ler under both hydroponic and soil culture conditions. For the estimation of Al tolerance in primary roots in hydroponic culture, the pH of the test solution containing 0–2.5 µM Al was adjusted to 5.2 with Hel to minimize proton toxicity. Under these conditions, the ecotype Ws was the most tolerant and Ler was the most sensitive to A1. The line A1-t was more tolerant to Al than the parental ecotype of Ler. The Al tolerance was also determined in a typical highly acidic nonallophanic andosol (Kawatabi Kuroboku) with different concentrations of exchangeable Al adjusted with various amounts of CaC03 and NaH2P04. The diameter of the rosette of each plant was measured as an indicator of Al tolerance under soil culture conditions. The order of Al tolerance under soil culture conditions among these ecotypes and the Al-t line was identical with that obtained under hydroponic culture conditions. Thus, we concluded that Al tolerance of A. thaliana in soils is strongly correlated with Al tolerance estimated under hydroponic culture conditions.