In vitrogermination and post-seminal development ofRuta graveolensL. under the influence of phenanthrene and benzo[a]pyrene

Abstract

Germinação in vitro e desenvolvimento pós-seminal deABSTRACT -Exposure to organic contaminants, such as polycyclic aromatic hydrocarbons, has attracted considerable attention due to the effects of these substances on human health, the environment and plant development. This study aimed to evaluate the influence of phenanthrene and benzo[a]pyrene on the germination and post-seminal in vitro development of R. graveolens. Decontaminated commercial seeds were inoculated in test tubes with an MS medium supplemented with 0 (control), 1.0, 5.0 and 10.0 mg L -1 phenanthrene and 0 (control), 0.001, 0.01 and 0.1 mg L -1 benzo[a]pyrene. The percentage of germinated seeds, germination speed index and entropy were evaluated. After two months, shoot and root length were all evaluated, and the number of developed leaves was counted. During the first month, the presence of phenanthrene did not alter the germination process, whereas benzo[a]pyrene at a concentration of 0.01 mg L -1 gave a significant increase in germination (p 0.05). During the second month, the concentrations of 5.0 mg L -1 phenanthrene and 0.001 mg L -1 benzo[a]pyrene resulted in significantly greater root development. No significant differences were found in biomass, shoot development or number of leaves per seedling. Such results suggest the potential for growing R. graveolens in contaminated areas at the levels studied.