Extrato de Moringa oleífera Lam. inibidor de fitotoxicidade de metais pesados no desenvolvimento de Lactuca sativa L.

Abstract

The industrial development after the population growth caused several concerns, one of which was the use of substances with heavy metals. These have xenophobic characteristics and represent a huge concern for human life, since they originate several diseases and cause the death of several biological beings. Several techniques are used to contain the contaminating power of metals. These include the use of biological materials as restraining agents or the reduction of harmful effects on biotic beings. The present work studied the influence of the Moringa extract on the reduction of heavy metals effects on the germinative process and the development of lettuce seedlings. The seeds were submitted to the twinning test with concentrations of heavy metals in mg L-1, these being Arsenic, Cadmium and Lead. For the phytotoxicity test of the extract in the germinative process, six concentrations of the extraction were used, with four replicates of each treatment. There was a significant difference among the heavy metals, the 0.9 and the 2.7 mg L-1 concentrations being the ones with the highest effects on the reduction of the seedling weight in the toxicology test. The second test showed a significant effect on germination, expressed by the concentration of 75 mg L-1 for the three metals, and also a reduction behavior in the variables of seedling and radicle sizes. The phytotoxicity test of the extract showed the power to inhibit the development of seedlings for all analyzed variables, the seedling size being the variable with greater interference in the highest concentrations of the moringa extract. The concentration 0.25 mg L, proved to be efficient in inhibiting the contaminating power of Arsenic and Cadmium.