Reactive oxygen species, antioxidant enzyme activity, and gene expression patterns in a pair of nearly isogenic lines of nicosulfuron-exposed waxy maize (Zea mays L.)

Abstract

Nicosulfuron is a post-emergence herbicide used for weed control in maize fields (Zea mays L.). Here, the pair of nearly isogenic inbred lines SN509-R (nicosulfuron resistant) and SN509-S (nicosulfuron sensitive) was used to study the effect of nicosulfuron on growth, oxidative stress, and the activity and gene expression of antioxidant enzymes in waxy maize seedlings. Nicosulfuron treatment was applied at the five-leaf stage and water treatment was used as control. After nicosulfuron treatment, the death of SN509-S might be associated with increased oxidative stress. Compared with SN509-R, higher O and HO accumulations were observed in SN509-S, which can severely damage lipids and proteins, thus reducing membrane stability. The effects were exacerbated with extended exposure time. Both O and HO detoxification is regulated by enzymes. After nicosulfuron treatment, superoxide dismutase (SOD), catalase, ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), glutathione reductase (GR), and glutathione-S-transferase (GST) of SN509-S were significantly lower than those of SN509-R. Compared to SN509-R, ascorbate content (AA), glutathione (GSH) content, GSH to glutathione disulfide ratios, and AA to dehydroascorbate ratios significantly declined with increasing exposure time in SN509-S. Compared to SN509-S, nicosulfuron treatment increased the transcript levels of most of the APX genes except for APX1, and in contrast to Gst1, upregulated the transcription of sod9, MDHAR, DHAR, and GR genes in SN509-R. These results suggest that on a transcription level and in accordance with their responses, detoxifying enzymes play a vital role in the O and HO detoxification of maize seedlings under nicosulfuron exposure.

Variant biochemical responses: intrinsic and adaptive system for ecologically different rice varieties

“…The deviation in SOD activity was observed which create separation in the action of SOD enzyme into 12 rice seedlings during their normal growth and development. SOD results of present study are in the accordance with earlier studies (Cavalcanti et al 2004 ; Wang et al 2018 ). SOD is most important primary enzymatic agent that transforms the superoxide into peroxide through dismutation of 2 molecule of superoxide (O 2 .− ) into hydrogen peroxide (H 2 O 2 ) and molecular oxygen (O 2 ).…”

Effects of fenclorim on rice physiology, gene transcription and pretilachlor detoxification ability

“…Excess ROS can damage plant cells by leading to membrane lipid peroxidation, protein oxidation, inhibition of enzyme activity, DNA and RNA damage, etc. and can even result in cell death [3][4][5][6][7][8].…”

“…One of their protective mechanisms is the antioxidant system, which is composed of a variety of enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) and other enzymes, for protecting against oxidative damage [7]. Antioxidant enzyme activity has been proven to be related to herbicide tolerance in a variety of plants [5,6,8,9].…”

Effects of fenclorim on rice physiology, gene transcription and pretilachlor detoxification ability

“…Excess ROS can damage plant cells by leading to membrane lipid peroxidation, protein oxidation, inhibition of enzyme activity, DNA and RNA damage, etc. and can even result in cell death [2][3][4][5][6][7].…”

“…One of their protective mechanisms is the antioxidant system, which is composed of a variety of enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX) and other enzymes for protecting against oxidative damage [5]. At present, antioxidant enzyme activity has been proven to be related to herbicide tolerance in a variety of plants [3,4,7,8].…”