Role of Heme Oxygenase-1 in Dual Stress Response of Herbicide and Micronutrient Fe in Arabidopsis thaliana .

Increasingly intensive agricultural practices are leading not only to herbicide contamination but also to nutritional stress on nontarget plants. This study evaluated the role of heme oxygenase-1 (HO-1) in the dual stress response of herbicide dichlorprop and micronutrient Fe in Arabidopsis thaliana . Our results revealed that co-treatment with 20 μM zinc protoporphyrin (a specific inhibitor of HO-1) reduced the activity of HO-1 by 21.6%, Fe 2+ content by 19.8%, and MDA content by 20.0%, reducing abnormal iron aggregation and oxidative stress in response to the herbicide compared to treatment with ( R )-dichloroprop alone, which has herbicidal activity. Thus, free Fe 2+ released from HO-1 mediated dichlorprop-induced oxidative stress in the Fenton reaction and affected aberrant Fe aggregation, which also had an enantioselective effect. This study contributes to an in-depth understanding of the toxicity mechanism of herbicides under nutrient stresses, thus providing new strategies to control the environmental risks of herbicides.