Abstract:
Eragrostis tef, a tall stature and highly nutritious cereal grown
in East Africa, has a serious lodging problem that reduces its
productivity considerably. Certain plant-growth regulators are
known to restrict growth and consequently improve lodging resistance
in cereals by affecting gibberellin biosynthesis. The effect
on height of growth regulator chlormequat chloride (CCC) was
determined for varieties Gea Lammie with a short phenotype and
DZ-01-196 with a tall phenotype. Chlormequat chloride decreased
plant height by 27% in Gea Lammie and by 46% in DZ-01-196.
More detailed analysis of growth regulator application by including
Paclobutrazol (PBZ) on the tall tef variety DZ-01-196 revealed
that both CCC and PBZ reduced culm length, but had no effect on
internode diameter. Chlormequat chloride at 100 mM especially
reduced the length of the lowermost internodes. Treatment with
CCC on the other hand did not increase panicle-bearing tillers, but
grain yield in CCC-treated plants was comparable to non-treated
control. The regulation of gibberellin biosynthesis could therefore
be a key target for improving lodging resistance in Eragrostis tef.