Effect in reducing maize plant height using growth regulators ethephon, chlormequat chloride (CCC), CCC + ethephon,
and mepiquat chloride + prohexadione-Ca was studied in field experiments during 2010 and 2011. It was found that
maize plant height could be reduced by as much as 125 cm (49% of control) using a double application of ethephon
(576 g a.i./ha) at growth stages BBCH 18–19 and BBCH 34–36. The other growth regulators displayed weak or no
influence. An optimum level of shortening was achieved using ethephon (576 g a.i./ha) at BBCH 34–36 (reducing plant
height by 40–90 cm), but it is necessary to count upon yield loss of 0.5–0.6 t/ha.