Potentials of nitrification inhibitors in modern N‐fertilizer management

Abstract

ZusammenfassungModern agricultural practices require a new concept of N-fertilizer management in order to optimize N-utilization and avoid N-losses. Nitrification inhibitors or ,,N-stabilizers" fit very good into this conception.Dicyandiamide (DCD) is an efficient nitrification inhibitor and blocks the first step of nitrification for 1-3 months (depending on temperature). This effect is bacteriostatic (not bactericidal) and does not affect other (esp. C-heterotrophic) soil microorganisms (,,biological activity"). DCD is a non-toxic, water soluble compound and will be degraded to COz, NH3 and H2O without any residues.There are various possibilities to use DCD: addition to liquid manure temporarily prevents oxidation of ammonium nitrogen e.g. of slurry or waste water from potato starch production.In combination with inorganic fertilizers like ammonium sulfate or urea (with 10 % of total-N) it enables the farmer to control NH4-supply to crop plants in certain stages of growth and to gain certain operational advantages by less frequently split applications of N especially on sand and rendzina soils.Thus, the systematic use of nitrification inhibitors not only represents a progress in agricultural technique but also helps to substantially reduce risks concerning pollution of surface and ground waters that are sometimes inevitable consequences of agricultural production. M6glichkeiten von Nitriflkationshemmatoffen in der modernen StickstoffdiingungModerne Landbewirtschaftungsmethoden erfordern ein neues Dungungskonzept rnit dem Ziel, die Stickstoffausnutzung zu optimieren und N-Verluste zu verhindern. Nitrifikationshemmstoffe oder ,,N-Stabilisatoren" passen gut in dieses Konzept. Dicyandiamid (DCD) ist ein wirksamer Nitrifikationshemmstoff; er blockiert den ersten Schritt der Nitrifikation fiir die Dauer von 1-3 Monaten (je nach Temperatur). Dieser Effekt ist bakteriostatisch (nicht bakterizid) und beeintrachtigt nicht andere (vor allem C-heterotrophe) Bodenorganismen (,,biologische Aktivitat"). DCD ist eine nicht toxische, wasserlasliche Verbindung, die letztlich zu C02, NH3 und HzO abgebaut wird ohne Ruckstande. Es gibt verschiedene Moglichkeiten ftir den Einsatz von DCD:Giille oder Abwasser aus der Kartoffelstlrkeproduktion (,,Kartoffelfruchtwasser") zugesetzt, verhindert es die Oxidation des Ammoniumstickstoffs fur eine gewisse Zeit.In Kombination mit anorganischen Diingemitteln wie Ammoniumsulfat oder Hamstoff (mit 10% vom Ges.-N) ist es moglich, die NHrN-Anlieferung zu Kulturpflanzen in bestimmten Entwicklungsabschnitten zu regulieren. Damit verbunden sind gewisse arbeitswirtschaftliche Vorteile gegeniiber iiblichen mehreren Teilgaben mit mineralischem Stickstoff vor allem auf Sanden und Rendzina-Boden. CW4-3263/861040%@%9 $ 02.50/0 0 VCH Verlagsgcsellnehaft mbH, D-6940 Wcinheim, 1986 470 Amberger Z. Pflanzenernaehr. Bodenk. Die Anwendung von Nitrifikationshemmstoffen stellt somit nicht nur einen Fortschritt dar in agrotechnischer Hinsicht , sondern tragt auch wesentlich dazu bei, mogliche Risiken einer Belastung...

The mobility of nitrification inhibitors under simulated ruminant urine deposition and rainfall: a comparison between DCD and DMPP

“…This is consistent with results of other studies, where DMPP has been found to have a longer residence time in comparison to DCD (Chaves et al 2006). DCD degrades to CO 2 and NH 4 + via guanylic urea, guanidine and urea (Amberger 1986;Kelliher et al 2008). The first stage of DCD degradation can occur on the surface of metal oxides, which catalyse the reaction of DCD and water to guanylurea (Hallinger et al 1990).…”

Plant acquisition and metabolism of the synthetic nitrification inhibitor dicyandiamide and naturally-occurring guanidine from agricultural soils

“…) to clover, suggest that plant uptake does take place (Amberger 1986;Di and Cameron 2004;Macadam et al 2003;Kelliher et al 2008). The occurrence of the structurally similar molecule guanidine (CH 5 N 3 ; Fig.…”

Coating of prilled urea with ecofriendly neem (Azadirachta indica A. Juss.) formulations for efficient nitrogen use in hybrid rice

“…About 90% of the world's rice is grown and eaten in Asia (De Datta, 1981), the continent which absorbs the major share of the global population increase. Fertilizer nitrogen has played a key role in increasing rice production in Asia, yet its use efficiency is only 30-40% or even less, because about 30-50% of the nitrogen applied is lost by runoff, leaching, ammonia volatilization and denitrification (Prasad, 1998a) The use of nitrification inhibitors (NI) along with nitrogen fertilizers has been suggested as a way of increasing nitrogen use efficiency (NUE) and the two most widely tested and marketed nitrification inhibitors are 2-chloro-6-trichloromethyl-pyridine and dicyandiamide (Amberger, 1986;Prasad and Power 1995;Trenkel, 1997). However, poor farmers in Asian countries who cannot even afford the fertilizer can hardly pay for nitrification inhibitors.…”