Maize crop


Nitrogen Stabilizer

Improve crop performance and sustainability through better control of nitrogen


  • Slow down the conversion of ammonium to nitrate and keep nitrogen available to crops for longer to optimise yield and quality.
  • Improve nitrogen efficiency in maize, cereals and oilseed rape.
  • Recent farmer trials show average yield increases of +10% in maize and +4.7% in winter wheat.
  • Improve farm sustainability by reducing nitrogen losses by up to 50% through leaching and greenhouse gases.
  • Use through existing farm sprayers or add to slurry.


Corteva Nitrogen stabiliser products feature Optinyte™ technology and are sold under the N-Lock™ and Instinct™ brands.


For more info call our Technical hotline:  0800 689 8899 or e-mail:


How Optinyte technology works

How Optinyte technology works

Nitrogen stabilisers help to keep nitrogen in the ammonium (NH4+) form for longer by slowing down the bacteria that convert ammonium to nitrite (NO2-). As ammonium is positively charged it is attracted to the negatively charged soil particles and is not washed out of the rooting zone. Nitrite and nitrate (NO3-) however are negatively charged and can be easily washed down the soil profile, away from crop roots. Optinyte keeps more nitrogen in the rooting zone for longer, improving the yield potential of crops. 

Benefits of using Optinyte in Maize

Optinyte maize benefits
  • Maize has traditionally been under-fertilised due to it requiring more than 50% of nitrogen post flowering.
  • Applying late nitrogen is impossible without crop damage and specialist equipment.
  • Optinyte products overcome this challenge by ensuring enough nitrogen remains in the root zone and available to the plant for as long as possible to maximise yield. 
  • Current RB209 gives N Max of 150 kg for maize - this is not enough for modern varieties.
  • Up to 60kg nitrogen can be lost pre-flowering.
  • Optinyte keeps a balance of ammonium and nitrate for maximum yield.
  • You only need to harvest one extra tonne of maize to cover the cost of applying Optinyte.  

About N-Lock™


  • Cereals
  • Maize
  • Oilseed Rape

Technical Specifications

Cereals, oilseed rape and maize

Application Timing:
During March for winter cereals. Before, at, or after drilling for Maize

Recommended Dose:
2.5 litre/ha

Water Volumes:
100 - 200 litres water/ha 400-600 litres liquid UAN/ha

Spray Quality :
MEDIUM as defined by BCPC

All conventional nozzles

Maximum Dose:
Do not apply more than a total of 5 L of N-Lock per hectare per year, 125 days must elapse between applications

Active Ingredient:
200 g/litre nitrapyrin

Pack size:
10 Litres

CS Capsule Solution (Microencapsulation)

How to use N-Lock - Maize

  • Apply muck / digestate and plough in (February - April)
  • Option 1
    • Apply before pre-drilling cultivations +/- glyphosate
    • Incorporation - soil movement to a depth of 50 mm and min tine spacing of 20 cm
    • If N-Lock is not physically incorporated to 50 mm, then 12 mm of rainfall is required within 10 days of application
  • Option 2
    • Mix with pre-em herbicide or liquid fertilisers if rain is imminent
  • Option 3
    • Wait until rain is forecast and apply alone (can be sprayed in then rain) at 100 L/ha water volume


How to use N-Lock - Cereals and Oilseed Rape

  • Apply using a farm sprayer
  • Rainfall (12 mm within 10 days of application) or several nights of heavy dew is needed to get the N-Lock into the soil
  • Can be applied in the rain (when applied alone)
  • N-Lock can be applied with T0's in winter cereals (see tank mix list)
  • N-Lock is best applied near to the main spring fertiliser application (typically March time, or early April further north).


Where should you use N-Lock?

  • Use where nitrogen losses can be high, such as permeable soils, or soils prone to waterlogging
  • Use on high potential crops where maximum nitrogen efficiency is required
  • Use as an aid to organic manure management
  • Use where a regular supply of nitrogen to the plant is required throughout its growing cycle


For more information download:

N-lock label
N-lock sds
N-lock tech sheet
N-lock tank mix


®™ Trademarks of Corteva Agriscience and its affiliated companies.
Use plant protection products safely. Always read the label and product information before use.