MEIOS ALTERNATIVOS PARA CULTIVO IN VITRO DE VIOLETA AFRICANA (Saintpaulia spp.) E EFEITO DE DESCONTAMINANTES NO CULTIVO IN VITRO DE PALMA FORRAGEIRA (Nopalea cochenilifera Salm-Dyck)

Abstract

The african violet (Saintipaulia spp.) is one of the most important ornamental houseplants distinguished by its beauty and delicacy of their flowers. The small forage cactus or sweet forage cactus (Nopalea cochenillifera Salm Dyck) stands out for its resistance to cochineal carmine. The plant tissue culture is becoming a very common technique. But for this technique to become viable, costs must be reduced. The objective of this work was to evaluate the development of african violet and forage cactus in alternative tissue culture media and alternative environments to cultivate in vitro. The work was performed at the Cell Biology and Tissue culture Laboratory of the CCA/UFPB - Areia - PB. The work was divided into three experiments, using a completely randomized design. In the first, sprouts of african violet with 0,5 cm containing two to three leaves were planted on MS medium + 20 g L-1 jellified sucrose agar and/or cassava starch to root. After rooting, the plants were taken for acclimatization. Were evaluated the percentage of rooting and survival; number of leaves and roots; length of sprout and root. Then, the sprouts were placed to root into medium semisolid and liquid using PVC bridges with filter paper or cotton, made the following assessments: survival and rooting; number of leaves and roots; length of sprout and root; fresh weight of sprout and root; dry weight of sprout and root. To the rooting were used five replications and three sprouts/pots and to acclimatization were used three plants/vase. In the last experiment we tested concentrations of sodium hypochlorite associated or not with Tween 20 in decontaminating forage cactus cultivation in vitro in a greenhouse. The variables analyzed were percentage of contamination; oxidation and the presence of sprouts. Were used 12 treatments and six replications. The cassava starch concentration of 100 g L1 can replace the agar in the culture medium of the culture of violet in vitro, being the most efficient concentration on rooting and acclimatization. The bridge PVC with filter paper can be used in the in vitro rooting african violet subjected to liquid medium. Maintenance of cladodes in sanitized environment associated with all treatments with NaOCl with or without Tween 20 is effective in decontamination of explants of forage Palm (N. cochenillifera), with a greater presence of shoots at concentrations of 10 and 20% of NaOCl, and occurring to decrease when associated with the Tween20.