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

Elrys, A.S., Abo El-Maati, M.F., Abdel-Hamed, E.M.W., Arnaout, S.M.A.I., El-Tarabily, K.A. and Desoky, E.M. (2021) Mitigate nitrate contamination in potato tubers and increase nitrogen recovery by combining dicyandiamide, moringa oil and zeolite with nitrogen fertilizer. Ecotoxicology and Environmental Safety, 209 . Art. 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; UreaRD), 75% of N recommended dose with DCD (Urea75%RD+DCD), Urea75%RD with 2% MSO (Urea75%RD+MSO2%), Urea75%RD with 4% MSO (Urea75%RD+MSO4%), Urea75%RD with 0.5 Mg ZE ha−1 (Urea75%RD+ZER1), and Urea75%RD with 1.0 Mg ZE ha−1 (Urea 75%RD+ZER2)]. 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+MSO4%, and Urea+ZER2. The highest NUE indexes were recorded in treatment Urea75%RD+DCD. The highest NO3- accumulation (567 mg NO3− kg−1) in potato tubers was recorded in treatment UreaRD. Whilest, the lowest NO3- content (81 mg NO3− kg−1) was in treatment Urea75%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.

Item Type:	Journal Article
Murdoch Affiliation(s):	College of Science, Health, Engineering and Education
Publisher:	Elsevier Inc.
Copyright:	© 2020 The Author(s).
URI:	http://researchrepository.murdoch.edu.au/id/eprint/59234

Item Control Page

Downloads