Paclobutrazol for Height Control of Petunias

Abstract

The effects of paclobutrazol on the height of Petunia × hybrida hort. ex E. Vilm. were studied. An experiment on 'Bravo F1' was performed at the National Institute for Agricultural Technology (INTA), San Pedro Agricultural Experimental Station (33º4' S, 59º4' W), Buenos Aires Province, Argentina, in the spring of 2006. Treatments consisted of three colours of flower (white, red and blue), four concentrations of paclobutrazol by irrigation (0, 5, 10 and 15 mg L -1 and three application times (at 10-12, 18-20 and 26-28 leaves). Height at 45 d after transplanting (dat), days to appearance, opening and fall of the first flower and number of flowers at 21 and 45 dat were registered. Differences between control plants due to flower colour were detected, and would indicate the need of a differential management: at 45 dat, the height of red-flowered plants (22.3 cm) was less (P < 0.05) than white-(25.2 cm) or blue-flowered plants (26.4 cm). Paclobutrazol allowed for reducing height in all treated plants. The minimal concentrations that induced maximum effects were: 10 mg L -1 for blueflowered plants (56% shortening), 5 mg L -1 for whiteflowered plants (40% shortening) and 10 mg L -1 for redflowered plants (38% shortening). In order to minimize the slightly deleterious effects detected in the number of blue and red flowers at 45 dat, early application would be advisable (10-12 leaves) for blue-flowered plants and more delayed (at 18-20 leaves) for red-flowered plants.

A Study on Plant Height Control of Iris Flowers

“…A delay was observed in some Iris cultivars in the visible appearance buds in plants treated with PBZ (Francescangeli, 2009). The application of PBZ delayed the appearance of the flower color in Petunia (Francescangeli and Zagabria, 2009). Flurprimidol application caused flowering delay of Ornithogalum saundersiae (Salachana and Zawadzińska, 2013).…”

Effects of different potting growing media for Petunia grandiflora and Nicotiana alata Link & Otto on photosynthetic capacity, leaf area, and flowering potential

“…and Nicotiana alata Link & Otto have become popular annual bedding ornamental plants and economically profitable potted plants cultivated in different growth substrates in greenhouses. Petunias belong to the Solanaceae family and are used in landscape, private garden, and building decoration (Dole and Wilkins, 2004;Arancon et al, 2008;Francescangeli and Zagabria, 2008;Xu et al, 2010), pharmaceutical and cosmetics industry, and phytoremediation (Watharkar et al, 2013). Nicotiana alata (ornamental tobacco) has a good potential for commercial horticulture and is also used in pharmacy or to provide antifungal substances for pathogens control (Gaspar et al, 2014).…”

Potted rose cultivars with paclobutrazol drench applications

“…The highest dose of PBZ extended flower longevity by 2.5 days relative to the control. FRANCESCANGELI & ZAGABRIA (2008) reported increased floral longevity of petunia with PBZ doses; however, SINGH et al (2016) observed reduced floral longevity of geraniums. According to OLSEN & ANDERSEN (1995), growth retardants generally reduce flower longevity, but it depends on the dose, species, and the retardant.…”