TESTS ON INHIBITION OF GERMINATION AND GROWTH OF CORN PLANTS IN THE PRESENCE OF TOXIC SUBSTANCES

Abstract

The paper presents the results of the germination tests and growth of corn seeds in the lab by exposing them to five concentrations of toxic substances. Nutrient solutions with five different copper sulfate concentrations or zinc sulfate concentration, were used for the tests, respectively 5 mg/L, 15 mg/L, 45 mg/L, 135 mg/L and 405 mg/L and a control variant with no toxic. Each of the variants were carried out in duplicate, and 5 corn seeds were added for each replicate. The exposure periods were 3 and respectively 7 days and after each established period of time, measurements were carried out for the length of the roots and stems. A series of observations, specific for each of the versions, was recorded. The results of the tests for revealed the following highlights: - From the tests we can see how low zinc ion concentrations (5 mg Zn/L and 15 mg Zn/L) have a more positive influence than copper ions on the germination and development of the roots and stems of corn plants. - Zinc ions have a positive influence in low concentrations (5 mg Zn/L) on roots (27,47 %) and stems (5 mg Zn/L and 15 mg Zn/L - 39,05% and 23,41%) during the germination period first 3 days, and a positive influence on stems growth (10 % compared to the control) of copper ions in small concentration (5 mg Cu/L) was registered on germination and growth of stems during the first 3 days.