A non-treated control was included for comparison. In 2004, an extra
application was made for all PGR treatments in order to better clarify the
proper application scheme. Thus, the treatments in 2004 were: PBZ at 12.5 + 12.5 g ai/ha, MPC at 25.0 + 25.0 g ai/ha and CCC at 1,500 + 1,500
g ai/ha. In this case, the first application of PGR treatments took place 26
days after sowing, at the four to five true leaves (BBCH 14-15) of
sunflower plants and the second application took place two weeks after
the first one, at the five to six true leaves (BBCH 15-16) (Meier, 2001).
The treatments were arranged in a randomized complete block design
with four replications. All PGRs were applied with a portable hand-held
field plot sprayer at 250 kPa pressure using a water carrier volume of
500 L/ha.