Mepiquat chloride and paclobutrazol in size reduction of Arundina graminifolia

Resumo

The objective of this study was to evaluate the effect of mepiquat chloride and paclobutrazol on reducing the size of Arundina graminifolia for commercialization as a flower vase. The experiment was conducted in a greenhouse with 50% of shading. Plants were grown in one-liter black polypropylene vase filled with commercial substrate Plantmax ® and sand in the ratio (1:1). Growth regulators were mepiquat chloride (Pix 50 g L-1), in doses of 1.0; 2.0; 3.0; 4.0 and 5.0 ml L-1, applied via foliar spraying and paclobutrazol (Cultar 250 g L-1), in doses of 1.0; 2.0; 3.0; 4.0 and 5.0 ml L-1 applied via substrate irrigation (50 ml per vase), another witness with distilled water. The applications of regulators was held every 15 days, during 5 months, totaling 10 applications. Been evaluated variables number and height of the shoots (cm) with and without flower. The experiment was conducted on a random block with 11 treatments and 10 replications. The paclobutrazol in dose of 2 mg L-1 applied via substrate fortnightly, totaling 10 applications is indicated for the reduction of the size of Arundina graminifolia, with doses greater than 3 mg L-1 present high number of dead plants. Mepiquat chloride in the doses studied was not effective in reducing the size of Arundina graminifolia. Growth reduction does not change the amount of shoots in the bamboo orchid.