Plant Tissue culture and Ultra High Diluted studies: suggesting a novel model using in vitro techniques
Keywords: high dilution, in vitro models, plant models
AbstractPlant tissue culture techniques have been used to evaluate the effects of many different substances and/ or conditions in plant growth and development. It provides information of great value about problems related to basic and applied aspects of plant as well as contributed to understanding of factors responsible for growth, metabolism, synthesis of secondary compounds, stress response. Considering all this wide range of applications and as all plant tissue culture techniques are undergone under axenic and controlled conditions (culture medium composition, light and temperature, for instance), it seems to be a value model for Ultra High Diluted (UHD) studies. Lippia alba is a Brazilian plant that tissue cultures protocols and in vitro essential oil production have already been described in scientific literature. None of all scientific papers evaluated the effects of UHD substances on in vitro development or secondary metabolic production. The main goal was to evaluate the use of plant tissue culture to investigate the effects of UHD benzilaminopurine (BA) on Lippia alba shoot culture. Nodal segments obtained from plants growth in vitro was subcultured to Murashigue & Skoog semi-solid medium added with 2ml of these different solutions: BA 3Âµmol, BA 12CH (10-24), water 12CH and water (no dilution and succussion). Weekly 1 ml of solutions were added to cultures. The experiment was repeated twice and each one consisted in 3 culture vessel with 5 nodal segments per treatment (n=30). All plants were maintained in growth room under controlled temperature (25Â°C), light and photoperiod (16L/8D). The tested substances were prepared according to the method of stepwise dilution and succussion as describe in Brazilian Homeopathic Pharmacopoeia. The experiment was blinded all the time. After 60d, plantlets were evaluated for number of shoots, shoot length, rooted plants (%), callus development (%) and fresh biomass. Data were submitted to ANOVA following by Duncanâ€™s and t-test. Plants from water 12CH and BA 12CH increased the number of new shoots and promoted the highest shoot length. By adding BA 3Âµmol the organogenetic response was inhibited since neither shoot nor root were developed. However, it was observed a significant basal callus development. Plant tissue culture could be adapted for UHD studies. More studies are being conducted in way to analyze other experimental conditions and biochemical/phytochemical parameters.