Modulating Growth, Flowering, and Biomass in Bougainvillea through Growth Retardants

Volume 14, Issue 55, 2025 (July – September)

Research Article
Modulating Growth, Flowering, and Biomass in Bougainvillea through Growth Retardants
Ritu Jain, G L Kumawat, Babita Singh and A K Tiwari
Keywords: dwarfing, plant growth retardants, bougainvillea, pot culture, paclobutrazol
DOI:10.37273/chesci.cs132056081

Full Text – PDF

Abstract

Bougainvillea (Bougainvillea spectabilis) is an important ornamental plant, but its vigorous growth habit limits its suitability for pots and compact landscapes due to frequent pruning needs. Plant growth retardants (PGRs) can help regulate plant size and improve flowering, yet limited information is available for bougainvillea. The present study evaluated the effect of paclobutrazol, cycocel (CCC), ethephon, TIBA and maleic hydrazide on growth and flowering in bougainvillea cv. Partha. The experiment was conducted in a Completely Randomized Design with 13 treatments and four replications, using rooted cuttings established in pots containing perlite and cocopeat (1:1). PGRs were applied as foliar sprays or soil drenches, and observations were recorded on vegetative and flowering traits. Results showed that paclobutrazol, particularly at 30–40 ppm as a soil drench, effectively reduced plant height, spread, shoot length, and internode distance, while improving growth index, flower index, and overall compactness. Maleic hydrazide strongly suppressed growth and completely inhibited flowering, while TIBA and CCC enhanced branching and leaf production at certain concentrations. In contrast, daminozide (5000 ppm) promoted plant height and spread but resulted in only moderate flowering, similar to the control. Overall, paclobutrazol at 30–40 ppm (drench) was most effective for inducing dwarfing and profuse flowering, making bougainvillea cv. Partha more suitable for pot culture, hanging baskets, and compact landscapes with reduced pruning needs.

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