Multiplicação in vitro de segmentos apicais caulinares de segurelha (Satureja hortensis L.)

Abstract

This study aimed to evaluate the effect of BAP in the presence and absence of NAA, on the in vitro multiplication of shoot apical segments of Satureja hortensis. The explants were isolated from seedlings germinated in vitro and cultured in nutrient medium MS. The experimental design was completely randomized in a 2×5 factorial arrangement, corresponding to the concentrations of NAA (0 and 1 μM) and BAP (0, 5, 10, 15 and 20 μM), with six replicates, each consisting of three explants. For the percentage of explants with shoots, there was no significant effect for the factor BAP, increasing as the concentration of BAP grows. The variable number of shoots per explant showed interaction between factors, with the highest shoot formation in the presence of NAA and BAP in the range of 10 -15 μM. In the presence of auxin, the highest value occurred with 15 μM BAP, tending to decline regardless of the presence of NAA. The rooting of the apical segments was higher in the presence of NAA and absence of BAP, decreasing with increasing cytokinin. Leaf number was influenced by the higher concentration of BAP, and the amount of 15 μMhadthe largest number, tending to decrease with increasing concentration. The concentration of 15 μM BAP, regardless of NAA, provided better results in the multiplication of the species, producing increased number of shoots and leaves, except for rooting, whichwas influenced by auxin.