The influence of the root zone temperatures on the phytoextraction of boron and aluminium with potato plants growing in the field.

The effect of different root zone temperatures on the concentration and content of B and Al in potato plants was examined using four different treatments of plastic mulches: T1: transparent polyethylene; T2: white polyethylene; T3: coextruded black and white polyethylene; T4: black polyethylene. An open-air treatment (T0) was used as control. The results showed significantly positive effects of the plastic covers on the root-zone temperatures: T0 = 16 degrees C, T1 = 20 degrees C, T2 = 23 degrees C, T3 = 27 degrees C, T4 = 30 degrees C. These different soil temperature conditions significantly altered the B concentrations, with T3 promoting the greatest concentrations and phytoaccumulation. The root zone temperature treatments induced higher concentrations and accumulation of Al in the T2 and T3 treatments in the roots, tubers, and leaves. The T2 and T3 lead to high levels of pectins in the roots, tubers, and leaves. This appears to reflect a possible mechanism of tolerance to the high Al and B concentrations in the analysed organs.