Enhancement of antioxidant defense and alleviation of oxidative stress in proso millet (Panicum miliaceum L.) using rice bran-coated urea under heat conditions

Document Type : Research Paper

Authors

1 Department of Plant Eco-Physiology, University of Tabriz, Tabriz, Iran.

2 Dryland Agricultural Research Institute, Agricultural Research, Education, and Extension Organization (AREEO), Maragheh, Iran.

10.22034/jppb.2026.70780.1403

Abstract

Objective: Heat stress triggers overproduction of reactive oxygen species, leading to oxidative damage and crop yield loss. This study investigated the efficacy of rice bran-coated urea in modulating the antioxidant defense system and mitigating oxidative membrane damage in proso millet (Panicum miliaceum L.) under field heat stress.
Methods: A two-year field experiment evaluated uncoated urea, rice bran-coated urea, gypsum-coated urea, and cement-coated urea at four nitrogen rates (0, 60, 80, and 120 kg urea ha-¹) under optimal (spring) and heat stress (summer) conditions. The experiment was a split-plot factorial design based on a randomized complete block design with three replications. The main plot factor was the planting season (spring and summer seasons). Sub-plot factors were the factorial combination of coating type and urea-N rate. The coating factor included uncoated urea (UCU, control), rice bran-coated urea (RBCU), gypsum-coated urea (GCU), and cement-coated urea (CCU). The urea fertilizers were 0, 60, 80, or 120 kg urea ha⁻¹. At the flowering stage, the catalase (CAT) and peroxidase (POD) activity, total soluble phenol content, total soluble protein content, and malondialdehyde (MDA) concentration were measured on the youngest fully expanded leaves. Grain yield was measured at physiological maturity from a 2-m² area in the central two rows of each plot.
Results: Across years, RBCU at 80 kg urea ha-¹ provided the most consistent balance between antioxidant protection and yield performance under summer heat stress. Under summer heat, RBCU significantly enhanced the enzymatic antioxidant shield, increasing CAT and POD activity, compared to the stressed uncoated urea control. It also elevated non-enzymatic defense by increasing total soluble phenols under summer heat compared with uncoated urea. This coordinated upregulation was associated with a significant containment of oxidative damage. While heat stress increased malondialdehyde content, RBCU at 80 kg urea ha-¹ resulted in lower MDA compared with the excessive 120 kg urea ha-¹ treatment. Concurrently, RBCU improved the total soluble protein content under stress. This physiological resilience was associated with improved agronomic performance; RBCU at 80 kg urea ha-¹ increased grain yield compared with the unfertilized control and outperformed uncoated urea under summer conditions.
Conclusion: RBCU-mediated nitrogen synchronization improved redox balance and limited lipid peroxidation under field heat stress, supporting both physiological stability and yield maintenance in proso millet.

Keywords

Main Subjects

References

Apel K, Hirt H. 2004. Reactive oxygen species: metabolism, oxidative stress, and signal transduction. Annu Rev Plant Biol. 55: 373–399. https://doi.org/10.1146/annurev.arplant.55.031903.141701
Beers Jr RF, Sizer IW. 1952. A spectrophotometric method for measuring the breakdown of hydrogen peroxide by catalase. J Biol Chem. 195(1): 133-140.
Bradford MM. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 72: 248-254. https://doi.org/10.1016/0003-2697(76)90527-3
Chance B, Maehly AC. 1955. Assay of catalases and peroxidases. Methods Enzymol. 2: 764-775. https://doi.org/10.1016/S0076-6879(55)02300-8
Fahad S, Bajwa AA, Nazir U, Anjum SA, Farooq A, Zohaib A, Sadia S, Nasim W, Adkins S, Saud S, et al. 2017. Crop production under drought and heat stress: Plant responses and management options. Front Plant Sci. 8: 1147. https://doi.org/10.3389/fpls.2017.01147
Farzane A, Nemati H, Shoor M, Ansari H. 2020. Antioxidant enzyme and plant productivity changes in field-grown tomato under drought stress conditions using exogenous putrescine. J Plant Physiol Breed. 10(1): 29-40. https://doi.org/10.22034/jppb.2020.12491
Gill SS, Tuteja N. 2010. Reactive oxygen species and antioxidant machinery in abiotic stress tolerance in crop plants. Plant Physiol Biochem. 48(12): 909-930. https://doi.org/10.1016/j.plaphy.2010.08.016
Hasanuzzaman M, Nahar K, Fujita M. 2013. Extreme temperature responses, oxidative stress and antioxidant defense in plants. In: Vahdati K, Leslie C (eds.) Abiotic stress—plant responses and applications in agriculture. London: Intech. https://doi.org/10.5772/54833
Heath RL, Packer L. 1968. Photoperoxidation in isolated chloroplasts. I. Kinetics and stoichiometry of fatty acid peroxidation. Arch Biochem Biophys. 125(1): 189-198. https://doi.org/10.1016/0003-9861(68)90654-1
Kabiri R, Naghizadeh M, Hatami A. 2016. Protective role of arginine against oxidative damage induced by osmotic stress in Ajwain (Trachyspermum ammi) seedlings under hydroponic culture. J Plant Physiol Breed. 6(1): 13-22.
Michalak A. 2006. Phenolic compounds and their antioxidant activity in plants growing under heavy metal stress. Pol J Environ Stud. 15(4): 523–530.
Mittler R. 2002. Oxidative stress, antioxidants and stress tolerance. Trends Plant Sci. 7(9): 405–410. https://doi.org/10.1016/S1360-1385(02)02312-9
Mittler R. 2017. ROS are good. Trends Plant Sci. 22(1): 11-19. https://doi.org/10.1016/j.tplants.2016.08.002
Nasibi F, Khodashenas M, Nasibi N. 2020. Priming with L-arginine reduces oxidative damages in Carthamus tinctorius seedlings under the toxic levels of lead. J Plant Physiol Breed. 10(2): 13-26. https://doi.org/10.22034/jppb.2020.13098
Peel MC, Finlayson BL, McMahon TA. 2007. Updated world map of the Köppen–Geiger climate classification. Hydrol Earth Syst Sci. 11: 1633–1644. https://doi.org/10.5194/hess-11-1633-2007
Raun WR, Johnson GV. 1999. Improving nitrogen use efficiency for cereal production. Agron J. 91(3): 357-363. https://doi.org/10.2134/agronj1999.00021962009100030001x
Reynolds M, Foulkes MJ, Slafer GA, Berry P, Parry MAJ, Snape JW, Angus WJ. 2010. Raising yield potential in wheat. J Exp Bot. 60(7): 1899–1918. https://doi.org/10.1093/jxb/erp016
Sarvari M, Darvishzadeh R, Najafzadeh R, Maleki H. 2017. Physio-biochemical and enzymatic responses of sunflower to drought stress. J Plant Physiol Breed. 7(1): 105-119.
Sharma A, Shahzad B, Rehman A, Bhardwaj R, Landi M, Zheng B. 2019. Response of phenylpropanoid pathway and the role of polyphenols in plants under abiotic stress. Molecules. 24(13): 2452. https://doi.org/10.3390/molecules24132452
Shaviv A, Mikkelsen RL. 1993. Controlled-release fertilizers to increase efficiency of nutrient use and minimize environmental degradation – A review. Fertilizer Res. 35(1): 1-12. https://doi.org/10.1007/BF00750215
Singleton VL, Rossi JA. 1965. Colorimetry of total phenolics with phosphomolybdic-phosphotungstic acid reagents. Am J Enol Vitic. 16(3): 144-158. https://doi.org/10.5344/ajev.1965.16.3.144
Trenkel ME. 2010. Slow- and controlled-release and stabilized fertilizers: An option for enhancing nutrient use efficiency in Agriculture. Paris: International Fertilizer Industry Association (IFA).
VaziriMehr MR, Sirousmehr AR, Ghanbari A, Fanaei HR. 2024. Effects of drought stress on yield and morphophysiological traits of quinoa (Chenopodium quinoa Willd) at different levels of nitrogen. J Plant Physiol Breed. 14(1): 107-123. https://doi.org/10.22034/jppb.2024.60013.1327
Velikova V, Yordanov I, Edreva A. 2000. Oxidative stress and some antioxidant systems in acid rain-treated bean plants. Plant Sci. 151(1): 59-66. https://doi.org/10.1016/S0168-9452(99)00197-1
Xu G, Fan X, Miller AJ. 2012. Plant nitrogen assimilation and use efficiency. Annu Rev Plant Biol. 63: 153-182. https://doi.org/10.1146/annurev-arplant-042811-105532
Zanganeh R, Jamei R. 2020. Nitric oxide production and antioxidants responses in maize under lead stress. J Plant Physiol Breed. 10(1): 51-60. https://doi.org/10.22034/jppb.2020.12493
 
 
 
 
 
 
 
Journal of Plant Physiology and Breeding
Volume 16, Issue 1
2026
Pages 55-73

Files

Share

How to cite

Statistics