Physiological Responses of Maize ( L.) Genotypes to Zea mays Cadmium Stress

Abstract

The research was performed to evaluate the influence of different levels of cadmium on various physiological parameters of maize ( L.). Three Iraqi varieties (5018, Baghdad-3, and Fajr-1) were exposed to four different concentrations of cadmium (0, 200, 300, 400 Zea mays ppm). The results revealed different variations in the ability of these varieties to withstand cadmium stress, in terms of accumulating some components in their vegetative parts. The results also indicated that Baghdad-3 had the highest total chlorophyll and total carotenoids content which recorded 0.853 mg g and 3.537 mg g ,​ respectively. The highest plant height (77.15 cm), shoot dry weight (11.35 g plant ), content ​of 1 1 1 proline (4.19 μmole g ), total nitrogen (1.2018%), and total protein (7.499%) were recorded with Fajr-1. The addition of cadmium resulted in a 1 decrease in plant height and shoot dry weight and an increase in all measured chemical contents. Higher levels of cadmium were accumulated in the shoot of variety 5018, while fajr-1 showed the least ability to absorb cadmium from the soil and accumulate it in its vegetative parts; the amount of cadmium accumulated by maize plant depends on its concentrations that added in the soil.