(294) The Effect of Heavy Metal Cadmium on Transgenic and Nontransgenic Petunia Plants

Abstract

Heavy metal contamination in the ground and its effects on human health has been a major concern. The objective of this experiment is to determine how cadmium affects transgenic and nontransgenic (control) petunia plants. Initially, the petunia seed germination medium (SGM) was prepared, and petunia seeds were sterilized and cultured on the SGM medium. During the actual experiment, using 8-day-old germinated petunia, the SGM-Cd media containing four different concentrations (0, 50, 100, and 200 μM) of CdCl2 were prepared. Plant growth and survival rates in four concentrations of SGM-Cd media were recorded. Over 20 days of observations, the plants showed two distinct differences: color and growth. For the first few days, all of the plants grew very slowly, but the plants showed marked differences in growth and color at later days. On the final day, 22 Jan., the control plants on 0 μM of CdCl2 grew 4.2 cm, while the transgenic plant grew 2.4 cm and showed a dark shade of green color. The control plants on 50 μM grew 1.38 cm, while the transgenic plants grew 2.2 cm. The control plants on 100 μM grew 1.14 cm, while the transgenic plants grew a total of 1.7 cm. Both control and transgenic plants on 200 μM had similar growth of 0.94 cm and showed very light shade of green color. The hypothesis in this experiment was confirmed because CdCl2 impacted the growth of the control and transgenic plants by stunting the growth of the plant and changing its color. It is also demonstrated here that transgenic plants containing the heavy metal transport (HMT) gene can grow better than control because of the specific HMT gene that allowed the plant to uptake more CdCl2 into the central vacuole.