Mitigate nitrate contamination in potato tubers and increase nitrogen recovery by combining dicyandiamide, moringa oil and zeolite with nitrogen fertilizer

Ahmed S Elrys; Mohamed F Abo El-Maati; Enas Mohamed Wagdy Abdel-Hamed; Safaa M A I Arnaout; Khaled A El-Tarabily; El-Sayed M Desoky

doi:10.1016/j.ecoenv.2020.111839

Mitigate nitrate contamination in potato tubers and increase nitrogen recovery by combining dicyandiamide, moringa oil and zeolite with nitrogen fertilizer

Ecotoxicol Environ Saf. 2021 Feb:209:111839. doi: 10.1016/j.ecoenv.2020.111839. Epub 2020 Dec 29.

Authors

Ahmed S Elrys¹, Mohamed F Abo El-Maati², Enas Mohamed Wagdy Abdel-Hamed³, Safaa M A I Arnaout⁴, Khaled A El-Tarabily⁵, El-Sayed M Desoky⁴

Affiliations

¹ Soil Science Department, Faculty of Agriculture, Zagazig University, 44511, Zagazig, Egypt; School of Geography, Nanjing Normal University, Nanjing 210023, China. Electronic address: aselrys@zu.edu.eg.
² Agriculture Biochemistry Department, Faculty of Agriculture, Zagazig University, 44511, Zagazig, Egypt.
³ Soil Science Department, Faculty of Agriculture, Zagazig University, 44511, Zagazig, Egypt.
⁴ Agriculture Botany Department, Faculty of Agriculture, Zagazig University, 44511, Zagazig, Egypt.
⁵ Department of Biology, College of Science, United Arab Emirates University, 15551, Al-Ain, United Arab Emirates; College of Science, Health, Engineering and Education, Murdoch University, Murdoch 6150, WA, Australia. Electronic address: ktarabily@uaeu.ac.ae.

PMID: 33385682
DOI: 10.1016/j.ecoenv.2020.111839

Abstract

Potato is considered a nitrogen (N) intensive plant with a low N use efficiency (NUE). The current study introduced an excellent approach by combining dicyandiamide (DCD), moringa seed oil (MSO), or zeolite (ZE), with N fertilizer for maximizing potato tuber yields and NUE as well as minimizing tubers nitrate (NO₃^-) accumulation. The impact of these materials on soil N availability and gaseous emissions (NH₃, and N₂O) was investigated under incubation conditions. A 2-year field experiment were carried out with seven treatments [without N (control), N fertilizer (350 kg N-urea ha^-1 as a recommended dose; Urea_RD), 75% of N recommended dose with DCD (Urea_75%RD+DCD), Urea_75%RD with 2% MSO (Urea_75%RD+MSO_2%), Urea_75%RD with 4% MSO (Urea_75%RD+MSO_4%), Urea_75%RD with 0.5 Mg ZE ha^-1 (Urea_75%RD+ZE_R1), and Urea_75%RD with 1.0 Mg ZE ha^-1 (Urea _75%RD+ZE_R2)]. We also conducted a 40-days incubation trial with the same treatments; however, urea was added at the rate of 200 mg N kg^-1 soil for all treatments, excluding the control. The addition of DCD, MSO, and ZE with urea under incubation conditions delayed the nitrification process, thereby causing a rise in NH₄⁺-N content and a decrease in NO₃^--N content. Ammonia-oxidizing bacteria (AOB) was inhibited (p ≤ 0.01) in treatments Urea+DCD, Urea+MSO_4%, and Urea+ZE_R2. The highest NUE indexes were recorded in treatment Urea_75%RD+DCD. The highest NO₃^- accumulation (567 mg NO₃^- kg^-1) in potato tubers was recorded in treatment Urea_RD. Whilest, the lowest NO₃^- content (81 mg NO₃^- kg^-1) was in treatment Urea_75%RD+DCD. The lowest cumulative N₂O emissions and highest cumulative NH₃ volatilization were observed in the treatment Urea+DCD under incubation conditions. Our findings demonstrated that N fertilizer rate could be reduced by 25%, while the tuber yields increased with an acceptable limit of NO₃^- content, resulting in economical, agronomical, and environmental benefits.

Keywords: Ammonia-oxidizing bacteria; Nitrate accumulation; Nitrogen recovery; Solanum tuberosum; Urea.

MeSH terms

Agriculture
Ammonia / analysis
Betaproteobacteria
Environmental Restoration and Remediation / methods*
Fertilizers / analysis*
Guanidines
Moringa*
Nitrates / metabolism*
Nitrification
Nitrogen / analysis
Nitrogen / metabolism*
Nitrogen Oxides
Soil
Soil Microbiology
Solanum tuberosum
Urea
Zeolites / chemistry*

Substances

Fertilizers
Guanidines
Nitrates
Nitrogen Oxides
Soil
Zeolites
Ammonia
Urea
dicyandiamido
Nitrogen