Two germinated seeds
were sown in a hole in a thin styrofoam board with 130-holes in
13 rows and a nylon net bottom. The styrofoam board was
floated onwater up to the two-leaf stage, and then the styrofoam
board with seedlings was transferred to a plastic box filled with
Yoshida cultural solution [17] containing 140 mmol·L−1 NaCl in
the screen-house of CAAS in Beijing. The solution was changed
every 5 days and the daily pH was maintained at 5.5. Each
styrofoam board had 240 plants from each population plus one
row of HHZ and IR29 (the salt sensitive check) placed in the
middle as checks and each population comprised two boxes.