Efeito de inibidores de crescimento e do tipo de poda em plantas utilizadas na arborização urbana

Abstract

The present study looked for alternatives of growth handling and of pruning in plants used in the urban forestation, seeking to the decrease of conflicts of these with electric power spinnings. In the chapter I experiments were accomplished with Flamboyant in soil and simple nutritious solution containing Al, with objective of studying handling alternatives seeking to reduce the growth and development of plantules Flamboyant. The aluminum atrophies roots could affect the growth. Six experiments were accomplished with plantules (soil and simple nutritious solution) in conditions of growth camera and vegetation house, Department of Fitotecnia - UFRRJ. In the soil experiments they were used two sources of sulfate of aluminum, being a commercial one and a pure source analytically, in the concetrations 0, 100, 200, 300 and 400 kg ha-1 in the soils Planossolo and Argissolo, with four repetitions. The experiments accomplished in simple nutritious solution just received calcium (0,001 mM) and they had as source AlCl3 with doses that varied from 0,075 to 5,0 mM. Through the results of the chapter I was ended that in same or superior conditions of soil concentrations to 0,4 Cmolc/dm3 of Al caused toxicity to the plantules of Flamboyant, with effects mainly in the length root, and in solution simple nutritious doses same or upper to 0,075 mM of AlCl3 paralyzed the growth root. Al can be used as inhibitor of vegetable growth in plantules of Flamboyant. The chapter II had as objective studies the effects of the pruning and association with growth inhibitors in arboreal species. Four experiments were accomplished with the plants Sabiá, Sombreiro, and Cucumber (phytotoxicity Evaluation the herbicides). The experiments were installed in the Department of Fitotecnia-UFRRJ, Seropédica. In the experiment 1 (Sabiá) all the plants were cut off 2 m of height, and they were applied the treatments: control, 2.4-D+Picloram, and Picloram. In the experiment 2 (Sabiá) all the plants were pruned removing 1/3 of the cup and applying the treatments: control, HCl, AlCl3, Picloram and nearby Cut (Without pruning of 1/3 of the cup). The experiment 3 (Sombreiro) had as treatments cut types in relation to the main trunk: nearby, leaving stub of 20 cm and of 40 cm. The experiment 4 (Pepino) it was installed in the originating from soil the first experiment with Sabiá. In the experiment 1, the treatment with Picloram delayed the beginning of the regrowth, important factor for the present study, so that they delay to arrive to the electric power spinning. In the experiment 2, just the treatment Picloram presented length and diameter of sprouts a little smaller in relation to the other treatments. In the experiment 3 it was verified that the nearby cut didn't present new budding until the 145 days after the pruning. In the experiment 4 the cucumber presented more intense toxicity in the treatment with Picloram. Was ended that Picloram and 2,4-D+Picloram were efficient for budding handling in adult plants of Sabiá, because they presented budding with small lengths, delaying the accomplishment of new pruning. In plants of Sombreiro the nearby cut was efficient, not presenting budding. It happened toxicity for Picloram in plants of Pepino.