Nitrogen and molybdenum fertilization influence on enzymatic activity and productivity enhancement of forage sorghum under water deficit in the Brazilian semi-arid region

Abstract

Water scarcity, combined with low soil fertility, constitutes one of the main limiting factors in crop productivity in semi-arid regions. However, nutritional supplementation techniques with nitrogen (N) and molybdenum (Mo) can lead to positive enhancements in the production of these crops. The objective was to evaluate the effect of increasing doses of N in the presence and/or absence of Mo on the activity of antioxidant enzymes and the productive increase of forage sorghum subjected to water deficit in the semi-arid region. The experiment was conducted in the field using a randomized block design, with four replications, in a 5 × 2 × 3 factorial scheme, comprising five doses of N (urea): 0, 50, 100, 150, and 300 kg ha⁻¹, two doses of Mo (sodium molybdate): 0 and 160 g ha⁻¹, and three production cycles. The highest yields of green mass (GM) (47.98 Mg ha⁻¹), dry mass (DM) (19.66 Mg ha⁻¹), water use efficiency (WUE) (5.57 kg/m³), and N use efficiency (NUE) (0.26 kg²/g) occurred at the highest N dosage (300 kg ha⁻¹ N). The highest contents and extraction of total N, Mo, chloride (Cl), and potassium (K) were found in regrowth 2 and at the highest N dose (300 kg ha⁻¹). The interaction of N and Mo resulted in higher catalase (CAT) enzyme activity. The meteorological conditions during the cycles strongly influenced the nutrient contents and extraction. The results of the study provide support for producers to use N and Mo fertilization strategies to improve crop productivity, even under water deficit conditions.

Keywords:

• Oxidative damage
• sodium molybdate
• Sorghum bicolor
• urea
• water stress

Acknowledgments

To the funding agency Foundation for the Support of Science and Technology of Pernambuco (FACEPE) for the financial support, enabling the execution of this research. To the Federal Rural University of Pernambuco, Academic Unit of Serra Talhada (UFRPE/UAST), and the Graduate Program in Plant Production (PGPV), for providing the field area, access to laboratory, bibliographical, and technological resources, fundamental for the advancement of this research. Lastly, to the Plant Nutrition research group of the semi-arid region, NutriPlant, for their collaboration and the opportunity to integrate a committed and dedicated research team.

Author’s contributions

All authors contributed to the conception of this study. Jamiles Carvalho and Alexandre Campelo designed, planned, and conducted the experiment, sharing co-first authorship. Additionally, Jamiles Carvalho supervised the entire project, from planning to the final writing, ensuring the accuracy and coherence of the work. Lucas Henrique, Glícia Rafaela, Gabriel Henrique, and Hugo Bentzen collected data and performed necessary analyses for the research. Thieres Freire and Evaristo Jorge conducted the statistical analysis of the data, assisting in interpreting the results.

Disclosure statement

The authors declare that they have no conflicts of interest related to this study.

Data availability statement

The data from this study are available from the corresponding author upon reasonable request.

Additional information

Funding

This study was supported by the funding agency Foundation for Support of Science and Technology of Pernambuco (FACEPE) through the IBPG-1648-5.01/21 project.