2. Materials and methods
2.1. Experiment design and set up
The soil for the experiment was collected at 0–20 cm depth
in the experimental field of the Paranaense University—UNIPAR,
Umuarama city, Paraná State, at coordinates S 23◦ 46 11.34 and
WO 53◦ 16 41.78 and at 391-m heightfrom sea level. A soil sample
was subjected to chemical characterization at “Solo Fétil” laboratory
(Table 1).
The soil was passed through a 0.4 mm sieve, and then 15 kg soil
was placed into two dark polyethylene bags for fumigation with
chloroformat 10 mL (CHCl3) kg−1 soil(Endlweber and Scheu, 2006).
After mixing the soil with chloroform, the bags were sealed and
left for three days of fumigation. Then, the bags were opened in an
exhaustion chamber where, they rested for one week before the
experiment took place.
Approximately, 20 cm seedlings of lemon grass were collected
atthe Medicinal Garden ofthe Paranaense University. The seedlings
were washed in water and disinfected in 70% alcohol for 1 min, and
one seedling was planted per pot.
All experimental units, with or without AMF inoculation, were
cultivated in 6 L pots with fumigated soil, some containing Pb
(NO3)2 and some not, according to their respective treatments. All
plants were grown in a greenhouse for six months.
To obtain 1000 mg Pb kg−1 of soil, we weighed
1614.4 mg Pb(NO3)2 kg−1 of soil and used the proportional rates