Paclobutrazol as growth regulator in Bahiagrass

Paclobutrazol como regulador de crescimento em grama batatais

Abstract

Bahiagrass (Paspalum notatum) is a native species widely found on highways margins, however, cutting practices are necessary, which increase the maintenance cost, being an alternative, the use of growth regulators, such as Paclobutrazol. Thus, the objective of the present study was to evaluate the use of Paclobutrazol doses as growth regulator in Bahiagrass. The turf was implanted in black plastic containers (8.46 L), previously prepared with the mixture of soil + sand + organic compost (1:1:1). The experimental design was completely randomized, composed of 3 doses of Paclobutrazol [1.1 and 2.2 kg a.i. (active ingredient) ha^-1 + control (0 kg a.i. ha^-1)], in four applications of 2 L of syrup per container, thus forming a factorial 3x4 (doses x response time) with 3 repetitions. The fresh and dry mass, relative chlorophyll index, leaf N and the visual aspect of the green cover rate were evaluated on four different dates. It was observed that the product controlled the growth of the lawn, with less production of fresh and dry mass, and increase of the relative index of chlorophyll and concentration of leaf nitrogen; however, it decreased turfgrass density of green mass, which influenced the visual lawn aspect. Thus, Paclobutrazol controlled Bahiagrass growth at a dose of 2.2 Kg a.i. ha^-1 in regular applications of 30 to 45 days, however it affected the density and consequently the aesthetics of the turfgrass.

Keywords:
Paspalum notatum; visual aspect; growth reducer; triazol