Artichoke micropropagation from in vitro germinated seedlings

Globe artichoke is a vegetable that can be consumed both fresh and industrialized, and its high nutritional and medicinal value arouses interest in its cultivation in Brazil. Micropropagation enables rapid multiplication of selected progenies. This study aimed to establish a micropropagation protocol for artichoke progenies using explants obtained from in vitro germinated seedlings. Cotyledon nodes of three progenies (P1, P2 and P3) were evaluated for multiplication rate, length and number of leaves over four successive subcultures on two media cultures (M1 and M2). In rooting phase percentage of rooted shoots, length of the longest root (cm) and root volume (cm(3)) were evaluated. In the acclimatization phase survival rate of shoots with and without roots was evaluated after 30 days of transplant in three different substrates. The culture medium M1 (1.0 mg/L BA and 0.1 mg/L NAA) promoted the best development of the axillary shoots and the multiplication rate of 5.1 for the progenies P1 and P2. The P1 progeny showed higher frequency of in vitro shoot rooting (51.9%) compared to the progeny P2 (14.9%). The substrates S1 (Mecplant Horta 2 (R) : 100%) and S2 (Mecplant Horta (R) 2: 50% and burned rice husk: 50%) were the most suitable for acclimatization of the micropropagated shoots of progenies P1 and P2, respectively, reaching a survival frequency of 75%. It was possible to establish the micropropagation for two progenies of artichoke selected for fresh consumption using as source of explant the cotyledon node obtained from in vitro germinated seedlings.