Maize test: what do the results reveal?
The previous issue of terraHORSCH focused on the role of starter nutrients in the early stages of maize development. The initial results of the tests are now available.
The tests were set up in spring in Austria, France, the Czech Republic and Germany. Seeding was carried out with a specially adapted Maestro 6 TV with an attached Leeb CT and various liquid fertiliser pipes. The objective was to examine the effects of starter nutrients on the development of maize plants.
Test results
Key questions were defined in advance, and their evaluation now reveals initial trends.
1.How can traditional DAP underground fertilisation be complemented or carried out with reduced quantities without losing yield? Can targeted liquid fertilisation in addition to DAP reduce the absolute amount of underground fertiliser while maintaining the yield level? DAP was tested with an NPK solution in various quantities and reductions.
In general, yield losses were observed without fertilisation. On average, the loss amounted to 7% across several sites – compared to the standard underground variant with 150 kg DAP. At the same time, we observed that a yield increase of 4% was possible with a lower amount of DAP.
A 50% reduction in nutrients, but with adjustment of the application points, resulted in only up to 2% less yield than the standard underground variant.
The conclusion: a reduction without major yield losses is possible – at least with the conditions of the test year. Although some sites showed lower yields if the reduction was very significant, the majority were very well supplied, and the required nutrients could be replenished at a later date. In general, you can say that with the same application of nutrients, but with adjusted placement and fertiliser form across several sites, a 2% surplus in yield could be achieved.
2.Are there any differences between pure nitrogen (AHL) and NPK solutions? In this test, only liquid fertilisation was used.
The lack of phosphorus was particularly noticeable in the cold spring and for plant growth. The delay in growth also had an impact on yield. Depending on which variants are compared, we observed yield differences of up to 6% between AHL and NPK. However, it is difficult to compare nutrients purely on the basis of N and P, but P did have a positive effect.
Depending on the site, the provoked burn with AHL resulted in a yield reduction by 20% as there was less plant population.
3.Can the yield level be secured against extreme weather or difficult conditions? Can targeted fertilisation make the population more resilient, enabling them to better withstand periods of heat and water shortage? These questions were examined with a variant with DAP and an NPK solution.
A significant cold spell occurred in Austria in spring. This is where the visual effect of starter fertilisation with P was most evident. Targeted starter fertilisation with liquid NPK as contact fertilisation in combination with DAP underground fertilisation with the same amount of N and P resulted in a 3% increase in yield compared to the standard 150 kg DAP underground variant.
In contrast to previous years, the crops did not have to struggle with severe drought, so it was not possible to analyse the effects in this respect.
4.Traditional solid fertiliser contact fertilisation with DAP directly in the row (without additional liquid fertiliser) is also part of the test series.
This resulted in a 4% higher yield than in the zero variant with lower DAP application (45 kg). This is a good option for starter fertilisation if the total nutrient supply is already secured by liquid manure or previous fertiliser applications.
Technical solutions
The tests will be repeated next year to further validate the results. At the same time, fertiliser application technology is developed further continuously. The new CLT system which can be retrofitted to the Maestro SV/SX offers an additional liquid fertiliser tank. This combines solid and liquid components in one machine. The combination of Leeb CT and Maestro TV/TX, RV/RX and CV/CX also offers this advantage.