Changes based on oxidative stress in metolachlor and atrazine treated maize seedlings

Abstract

The present study investigated biochemical effects of Atrazine (0, 200μM , 500 μM and 1000 μM) and Metolachlor (0, 100μM , 500 μM and 1000 μM) concentrations applied to 15-day-old seedlings of three maize varieties (Zea mays L., cv. Saccharata, cv. Danona, and cv. Advanta 2898) for 48 hr. Hydroponic environment was preferred for all treatments for the seedlings. Compared to their controls, GSH/GSSG ratio was decreased, SOD activity was increased, and CAT activity was also decreased/decreased in root/leaf of Atrazine treated maize seedlings. While % ratios of fatty acids in leaf was increased for palmitic acid and palmitoleic acid in cv. Saccharata and advanta 2898, but was decreased in cv. Danona. While the rate of linoleic acid was increased in leaves in other two ratios but decreased only in cv. Saccharata; linoleic acid was increased only in cv. Saccharata and decreased in others. Compared to their controls, in root/leaf of maize seedlings treated with Metolachlor; GSH/GSSG ratio decreased/increased, SOD activity decreased/increased, and CAT activity decreased/decreased. While % ratios of fatty acids in leaf showed an exceptional increase and increase for linolenic acid, palmitic acid, and linoleic acid; palmitoleic acid and stearic acid decreased and palmitic acid decreased only in cv. Advanta 2898. Generally, the inhibitive effect of the herbicides Atrazine and Metolachlor elevated in parallel to increased dose (1000 μM).However, Atrazine displayed a more oxidative damagesthan Metolachlor on three maize varieties.

Application of a Plant Biostimulant To Improve Maize (Zea mays) Tolerance to Metolachlor

“…Although the primary site of action of this herbicide is still uncertain and strictly dependent on plant species, the active compound can interfere with plant growth and development, triggering oxidative stress, inhibiting long chain fatty acids , and cell division, and compromising the membrane permeability of root cells . In graminaceous crops, such as rice or maize, metolachlor caused oxidative stress and decreased plant biomass production. − Our results showed that Megafol significantly reduced the toxic effects of this chemical (Figures and ). No literature reports document such an ability of a biostimulant to counteract the phytotoxic effect of a herbicide.…”

“…Plants subjected to abiotic stresses can undergo the oxidation of unsaturated fatty acids, which is provoked by reactive oxygen species (ROS) . Herbicides are well-known to give rise to oxidative perturbations that can increase or decrease enzymatic activities such as catalases , and peroxidases depending on the species . For this reason, the content of MDA, a product of lipid peroxidation, was investigated in plants treated with metolachlor in combination or not with Megafol, since this parameter is an important indicator of lipid degradation in response to the treatments.…”