Biometria e avaliação dos efeitos ecotoxicológicos do chumbo na germinação do gergelim (Sesamumindicum L.).

Abstract

Sesame (Sesamunindicum L.) is an oilseed crop adapted to semi-arid conditions in various parts of the world with high economic potential and possibilities in both the national and international market. The aim of this study was to analyze and evaluate biometrics ecotoxicological effects of lead on seed germination and seedlings of sesame (Sesamumindicum L.), to evaluate and compare the physical and physiological qualities among cultivated seeds in Brazil.The seeds used to conduct this study were acquired in Agronomic Institute-China IAC (IAC China), Sao Paulo. During the research it was determined the weight of a thousand seeds, biometric characterization of seeds: length, width, thickness, elongation, in three dimensions, geometric mean diameter, surface area, volume, sphericity, bulk density and preparation of solutions of lead. For toxicological analysis revealed the following parameter settings: percentage of germination and normal seedlings, germination speed index (GSI), mean germination time (MGT) seedling growth after 24h, 48h, 72h and 96h of seeding. in still lead to germination has been found that the application of larger doses of lead has resulted in the absence of aerial part (PA) and part of the root (PR) occurs to the exclusion of germination.Lead showed significant inhibitory potential in the growth of shoots and roots of seedlings. Lead concentrations equal to or greater than 6.0 mmol increased the number of abnormal seedlings planting in the order of 3 to 4 times decreased the growth of the aerial parts and roots of the seedlings. Concentrations of 4.0 and 6.0 mmol of lead caused a 50% inhibition of the growth of shoots and roots, respectively.