Abstract:
Pelargonium
Key Words: Alar, Bonzi, CCC, Method of application, Time of application,
peltatum, commonly grouped as Ivy geranium, shows stretching growth habit
with little number of lateral branches due to these characteristics of the species it is difficult
to produce more-compact, attractive, and salable cuttings. When cultivated in containers for
cuttings production, this species grows up quickly and fall-over the pots. To manage the
problem growers regularly use plant growth retardants (PGRs) like Alar, CCC, Bonzi, and
Florel. However, the main limitations with the use of these chemicals are misapplication
related to defining the right type of chemicals, method and time applications of them for the
crop. Therefore, this experiment was initiated to assess the Influence of Method and Time of
Application of Selected PGRs on Growth of Ivy Geranium. The study was conducted at Jimma
University College of Agriculture and Veterinary Medicine under greenhouse condition. It
was laid out with 3 x 2 x 2 factorial arrangement with three replications in Randomized
Complete Block Design (RCBD). The application of plant growth retardants on the tested
plant brought changes on Number of Leaves per plant, Leaf Area, Number of Branches per
plant, Plant Height, Inter-node Length, Main Stem Diameter, Root Length and Root Volume
but not on Root Number. Number of Leaves per Plant, Number of Branches per Plant, Main
Stem Diameter and Root Volume of the test plant significantly (p<0.05) increased with the
application of plant growth retardants. Conversely, Leaf Area, Plant Height, Inter-node
Length and Root Length showed notable reduction. Number of branches per plant was
increased by 53.66% from the control in response to two way interaction effects of plant
growth retardants and their method of applications (p< 0.01). The increase in number of
branches is associated with the reduction of plant height (56.74%) in response to three way
interaction effects of plant growth retardants, their method and time of application (p< 0.01)
and inter-node length (32.18%) in response to two way interaction effect of plant growth
retardants and their method of applications (p< 0.05). Bonzi plant growth retardant was
found to be the most strong, while Alar was the weakest to suppress the stretching habit of the
plant under investigation. The two way interaction effect of plant growth retardants and
drench form of application was found more effective than spray application of plant growth
retardants under investigation. Moreover, the three way interaction effect of plant growth
retardants, drench application and early stage application was found very effective to restrict