Micropropagação da amoreira-preta (<em>Rubus</em> spp.) e efeito de substratos na aclimatização de plântulas

Abstract

Blackberry micropropagation (Rubus spp.) and effects of substrates in plants acclimatization. The objective of the present study was to achieve the improved techniques in in vitro propagation and to determine a better substrate for the blackberry. The first experiment consisted of nodal segments of plants with ±2 cm of length obtained from in vitro culture cv. Ebano, excised and inoculated in MS culture medium, supplemented with five activated charcoal concentrations and five BAP concentrations. Both experiments were entirely performed in a design randomized complete block, using in vitro 3 explants by repetition and 4 replications for treatment and in greenhouse, a factorial 4x4. The pH of the culture medium was adjusted to 5.8 before the addition of 6 g L -1 of agar and the sterilization to 121oC and 1 atm for 20 minutes. After 70 days, several parameters in the explants were evaluated. A greater number of leaves and roots were obtained with 0.5 mg L -1 of BAP. The number of roots and their length were larger in the presence of 3 g L -1 of activated charcoal. A larger weight of the fresh matter was obtained in the absence of activated charcoal. The second experiment consisted of plants cv. Cherokee maintained in in vitro conditions and transplanted to plastic trays, containing the substrates and kept in greenhouse. Four types of substrates were tested. After 100 days of acclimatization, the leaf number, root length and aerial part, cool and dry root weight and cool and dry aerial part weight had been evaluated. It was concluded that the acclimatization can be successfully performed using Plantmax  followed by the Plantmax  + vermiculita + rind rice carbonized mixture. There was a 92% rate of the plants' survival in all substrates.