Indução à ploidia em Ananas comosus var. erectifolius (L. B. Smith) Coppens & Leal, na Amazônia Ocidental

Abstract

The protection of the Amazon rainforest ecosystems allows the conservation of tropical biodiversity and the opportunity to carry out the sustainable management of non-timber forest products, mainly in poor regions, as an alternative for social and economic development for local populations and riverside communities. In this Amazonian biodiversity, in the field of vegetable fibers, there is a plant that presents potential for the production of lignocellulosic fibers, Ananas comosus var. erectifolius, popularly known as curaua. Due to its productive potential with fiber, it is necessary to seek greater knowledge of conservation and management of this species and to initiate research aimed at its genetic improvement. In this sense, the objective of this work was to establish a ploidy induction protocol in Ananas comosus var. erectifolius in samples collected in the Western Amazon, aiming at increasing the genetic variability for the purpose of plant improvement of this fibrous plant. For ploidy induction of A. comosus var. erectifolius, rhizomes were acquired. These were collected in the production area of the UFAM experimental farm. The rhizomes were immersed in a solution of water and sodium hypochlorite in a 95:5 ratio. After cleaning the rhizomes, the ploidy induction procedure was performed. The rhizomes were submerged under agitation in different colchicine concentrations (0; 0.05; 0.10 and 0.20%) and exposure times (2; 4 and 6 hours). After exposure, treatments were immediately planted in 4 trays containing commercial substrate. The experiment was conducted in a factorial arrangement of 4 (colchicine doses) x 3 (exposure time), in a completely randomized experimental design. Each treatment consisted of 15 rhizomes. Data were subjected to analysis of variance and means compared using the Scott Knott test at 5% probability. Colchicine proved to be toxic to curauá rhizomes, causing significant reductions in the average number of shoots and an increase in the percentage of non-emerged plants, compared to the control, at different colchicine concentrations and times of cultivations tested.