Micropropagação das bananeiras 'Prata-Anã' e 'FHIA 01' a partir de explantes de plantas tratadas com paclobutrazol

Abstract

Com o objetivo de avaliar o desenvolvimento in vitro de explantes das bananeiras ‘Prata-Anã’ e ‘FHIA 01’ provenientes de plantas tratadas com paclobutrazol (PBZ), conduziu-se este experimento no Laboratório de Cultura de Células e Tecidos Vegetais, Setor de Fruticultura, DFT/UFV. Utilizou-se esquema fatorial 2 x 5, correspondendo às duas cultivares (‘Prata-Anã’ e ‘FHIA 01’) e cinco doses de PBZ (0,0; 0,5; 1,0; 1,5 e 2,0 g i.a. planta-1), em delineamento experimental inteiramente ao acaso, com número variável de repetições. Avaliaram-se, na parte aérea: taxa de brotação, altura e diâmetro, número de folhas, massa fresca e seca e intensidade da cor verde; e no sistema radicular: porcentagem de enraizamento, número de raízes, comprimento da maior raiz, massa fresca e seca, e a relação massa da raiz:massa da parte aérea. Foi observado que a altura da parte aérea foi reduzida a partir de 1,13 g i.a. planta-1, em ambas as cultivares. O diâmetro não foi alterado com o aumento das doses, mas nos explantes da ‘Prata-Anã’ os diâmetros foram maiores que ‘FHIA 01’. Para o número de folhas, as massas fresca e seca não apresentaram diferenças entre as doses e entre as cultivares. A intensidade da cor verde aumentou linearmente com o aumento das doses, em ambas as cultivares. A partir de 1,07 g i.a. planta-1, a taxa de brotação da ‘Prata-Anã’ foi inibida, enquanto a da ‘FHIA 01’ foi estimulada a partir de 0,85 g i.a. planta-1. Houve interação significativa para a porcentagem de enraizamento, onde se observaram valores mais baixos para a cultivar ‘Prata-Anã’ (64,71%), em relação à ‘FHIA 01’ (95,83%), na maior dose. Não foi observado efeito das doses de PBZ sobre a porcentagem de enraizamento de explantes da ‘Prata-Anã’, enquanto para ‘FHIA 01’ houve aumento linear do enraizamento com o aumento das doses, sendo que o maior valor encontrado foi de 95,18%. As demais características aumentaram linearmente com o aumento das doses de PBZ, para ambas as cultivares.

With the objective of evaluating the development of in vitro explants of banana trees ‘Prata- Anã’ and ‘FHIA 01’ originated from adult plants treated with paclobutrazol (PBZ), this experiment was conducted at the Laboratory of Tissue and Cells Culture, Pomology Section, DFT/UFV. A factorial scheme 2 x 5 was used, corresponding to the two cultivars (‘Prata Anã’ and ‘FHIA 01’) and five doses of PBZ (0.0, 0.5, 1.0, 1.5 and 2.0 g i.a. plant-1), arranged in an entirely random design, with different number of replicates. It was evaluated on the aerial part: the rate of sprouting, height and diameter, number of leaves, fresh and dry mass and intensity of the green color; and on the root system: percentage of rooting, number of roots, length of the largest root, fresh and dry mass, and mass of the roots:mass of the aerial part relation. The height of the aerial part started to be reduced from the dose of 1.13 g i.a. plant-1 in both cultivars. The diameter was not altered with the increase of the doses, but in the explants of ‘Prata-Anã’ it was observed larger diameters compared to ‘FHIA 01’. The number of leaves, the dry and fresh weight did not suffer alterations among the different doses, nor between cultivars. The intensity of the green color increased linearly with the increase of the dose in both cultivars. Starting from the dose 1.07 g i.a. plant-1 the rate of sprouting for ‘Prata-Anã’ was inhibited, while there was an enhancement of the rate for ‘FHIA 01’ starting at dose of 0.85 g i.a. plant-1. There was significant interaction for the percentage of rooting, with lower values for the cultivar ‘Prata-Ana’ (64.71%) compared to ‘FHIA 01’ (95.83%) for the higher dose. It was not observed effect of the doses of PBZ about the percentage of rooting of the explants of the cultivar ‘Prata-Anã’, while for ‘FHIA 01’ there was linear increase with the dose elevation, with the largest rooting value of 95.18%. The other characteristics there were linear increase with the increment of PBZ doses, for both cultivars.