The roots were gently shaken, soil still adhering to the roots
was considered rhizospheric soil, and it was separated from the
roots and stored in sealed sterile plastic bags. Roots (diameter
1 mm) were carefully washed with tap water, chopped into 1-cmlong
pieces, and
fixed in a formalin/acetic acid/ethanol (FAA,
13:5:200, v/v/v) solution for 24 h, and stored for subsequent
analysis. Soil samples were air-dried for 2 weeks, ground by hand,
passed through a 2-mm mesh screen, and then stored at 4 C before
analysis.