Utilização de paclobutrazol em vetiver na produção de mudas e seu efeito em plantas no campo

Abstract

Utilization of paclobutrazol in vetiver for plantlet production and its effect over plants in the fieldThe effect of paclobutrazol was evaluated on plantlet production of different vetiver genotypes (assay 1) and on plants under field conditions (assay 2). In the first assay, two vetiver genotypes from the Germplasm Repository of Sergipe Federal University, Brazil (UFS-VET001 and UFS-VET003), seven concentrations of paclobutrazol and two moments of application (7 and 14 days after planting) were evaluated. In the field assay, the treatments were three vetiver genotypes and three methods of application of paclobutrazol. Two product applications were performed at plantlet stage and one when plants were in the field. The application on 14-day old plants in the nursery reduced plant height and dry weight ofaerial part and roots. The highest paclobutrazol concentration (1,800 mg l-1) resulted in shorter plants and lower dry weight of aerial part. Paclobutrazol did not influence the number of tillers per plant and should not be recommended for production of vetiver plantlets. In the field assay, the genotypes UFS-VET001 and UFS-VET004 had major tillering at 133 days after transplanting; there were no significant differences between the genotypes for the variables number of ears, plant height, dry weight of aerial part and roots, and essential oil content. The application of paclobutrazol proportioned reduction on the number of ears and plant height, but did not affect dry weight of aerial part and roots. Paclobutrazol should not be recommended for commercial production of vetiver roots because it did not reduce the aerial part and did not increase roots and essential oil yield as well.

Substrate Volumes and Application of Paclobutrazol for Ornamental Pepper Production

“…These results agree with those obtained in soybean, where the application of PBZ resulted in plants with lower fresh mass and dry mass seven days after application (Cruciol et al, 2014). In Vetiver (Chrysopogon zizanioides), the application of different doses of PBZ via substrate resulted in seedlings with lower dry mass production of the root system, regardless of the doses applied (Blank et al, 2009).…”

Paclobutrazol as growth regulator in Bahiagrass

“…(active ingredient) ha -1 + control (0 kg a.i. ha -1 ), applied 2 L of syrup per container, directly on the substrate, as product is absorbed by roots (McCarty, 2008;Blank et al, 2009). The Paclobutrazol application dates were 0, 28, 55 and 78 days after the installation of the experiment (DAIE).…”

“…Paclobutrazol acts on the synthesis route of gibberellins, and interferes in phase 2, that is, it blocks the action of the enzyme Kaurene Oxidase, which inhibits the conversion of kurene into kaurenol and, consequently, prevents the formation of any type of gibberellin as well as cellular elongation, creating compact leaf (McElroy, 2012;March et al, 2013;Glab et al, 2020). When applied directly to the soil or substrate, it has greater activity and efficiency compared to foliar application, as it is translocated almost exclusively by xylem and less by phloem, where it is absorbed by the roots and moved directly to the growth points (McCarty, 2008;Blank et al, 2009).…”