Abstract
The Hackensack Meadowlands is a salt marsh, and its sediments contain high levels of heavy metals, including chromium (Cr), Copper (Cu), Zinc (Zn) and Lead (Pb). Exposure to excessive amounts of heavy metals may lead to increased oxidative stress and cellular damage in non-halophytic plants, which subsequently causes stunted growth, impaired protein metabolism, and altered water balance and nutrient absorption. In this study, we quantified the inhibitory effects of salt, Copper and Zinc on garlic plants, a fast-growing culinary and medicinal species. The garlic cloves were germinated in deionized water and then treated with one of the following solutions: 1) NaCl; 2) 4 CuCl2; 3) ZnCl2; 4) CuCl2+ 2 mM ZnCl2; 5) Control (deionized water). Our results indicated that the combined “copper + zinc” treatment resulted in most growth inhibition as manifested by fewest roots, shortest and fewest leaves, and least amounts of leaf photoreceptors (chlorophylls and carotenoids). Garlic roots exposed to heavy metals had significantly lower protein contents, indicating severe damages in the roots which made it impossible for garlic to absorb the necessities to develop into a healthy plant. The protein contents in garlic leaves were not reduced, and the combined “copper + zinc” treated garlic leaves even had higher protein contents than the control plants. This result suggests that exposure to heavy metals might have stimulated overexpression of certain photosynthetic protein enzymes. Overall, our findings emphasize how exposure to high concentrations of heavy metals impaired plant growth correlating to the severity of ecological stressors.
Details
Presentation Type
Theme
Food Production and Sustainability
KEYWORDS
SALINITY, HEAVY METAL, STRESS, GARLIC
