Study on the Effect of Cadmium Stress on Rice Seed Germinations

Abstract

This study investigates the effects of cadmium (Cd) stress at different concentrations on rice seed germination and physiological metabolism. The results show that under medium to high Cd concentrations, both the germination rate and germination potential of rice seeds significantly decreased, with a particularly pronounced inhibitory effect on the root system. The research concludes that Cd stress disrupts rice seed germination through a dual mechanism of "inhibiting starch catabolism" and "impeding substance transport." Firstly, it suppresses the activity of α- and β-amylase, reducing the consumption rate of stored substances and cutting off the energy source for germination. Secondly, it induces oxidative stress (SOD and POD activities exhibit a "low-promotion, high-inhibition" response, while MDA content significantly increases), damaging the cell membrane system and severely hindering the transport efficiency of stored substances to the seedlings. This disrupts the energy supply during rice seed germination, leading to growth inhibition. These findings provide theoretical support for mitigating Cd pollution through root system protection and metabolic regulation.