Application of liquid fertilizer ina future oriented agriculture
Guest commentof Mr. Michael Fuchs, SKW, LF application research
department

APPLICATION OF LF IN A FUTURE
ORIENTATED AGRICULTURE
Guest comment of Mr. Fuchs, SKW, LF application research department

The demands of theworldwide markets force
the farms to optimize thespecial intensity, means
also lowering costs. One
opportunity is the substitution of granulated fertilizer
by liquid variances. The
advantages are not only
based on the cheaper
nitrogen price.

LF includes further positive characteristics whichcontribute to a positiveresult.
One characteristic is thesame but mostly higher
eﬃciency of LF comparedto granulate.
But in practice there is
still uncertainity about theuptake via leaves and therisk of scorching. Highscorching will lead tolower yield.
Therefore the right choiceout of the variances of LF
is required for a successful
fertilizing.

technology contributes toa positive result.

Additionally the rightnozzle and application

Impact of LF
In Germany the percentage of LF in relation to the total
nitrogen market stayed on average last 10 years at a levelof 13 – 15 % constantly. In the same period the granulated
KAS dropped down from 61 to 50 %. The most applied LF
was a LF with a share of 28 – 30 % nitrogen. This kind of LF
is tolerated best by the crops.

Very positive effects can be gained with the new
PAISIN-S 25/6 and Alzon Liquid - S25/6 (25% N, 6% S).
The optimum concentration of sulfur is 3 – 5 %, due to crop
tolerance. The sulfur in the combined N-/S-LF is available
immediately for the crop, as sulfate or ammoniumthiosulfate.

APPLICATION OF LF IN A FUTURE
ORIENTATED AGRICULTURE
Guest comment of Mr. Fuchs, SKW, LF application research department

Uptake via soil (roots)or leaves
Researches of industry andgovernmental institutes
verify the efficiency of LF incompari-son to granulated
fertilizers. (See table 1) Scientific resear-ches confirm thatduring a vegetation period
the kind of fertilizer used
influence on the yields is only
marginal, but in the averagea number of years there is no
significant difference. But in adry spring and early summer
time periods LF has evident
advantages compared togranulated ones.
The reason is related on ahigher level of leaves uptakeof LF.

The question if the N fertilizer
application should be granulated or liquid is secondary.
Important is the price-ratio
performance and the technical resources of the farm.
From the experience there areno big differences between
the most common fertilizers

CerealRapeseed

CornPotatoes

Sugar beets

Total

Number of tests

155

1525

28

21244

without N

6773

9082

9474

PIASAN® 28100(90.1 dt/ha)
yield100(40.6 dt/ha)
yield100(97.7 dt/ha)yield

100(432 dt/ha)
yield100(677 dt/ha)
yield

100

KAS

10099

99

99

99

100

KAS, nitrogen-LF and urea.
This is valid if all basic rules
and requirements have been
fulfilled.

Table 1: Comparison of yields fertilized without or different types of nitrogene, average of yields 1993 – 2010, 3 different test
areas in Saxonia, Niedercunnersdorf, Trossin and Rosenow.

LF quality secures yield
LF is a pressure less fluid which can be applied by conventional plant protection sprayers. Besides the application
technology the quality of the LF is important for a successful
crop adaption. The risk of scorching is then very low under allconditions, also in very sensitive situations. This is also valid incombination with pesticide application.

Positive experiences enable the farmer to repeat this in thefollowing years. Premium quality LF, like PAISIN® 28 from SKW
guarantees beside a precise labeled nitrogen component:High surface tension
pH value close to neutral
Low level of Biuret content
These quality characteristics are not mentioned in the governmental fertilizer directives but are essential for the successful
application of LF.

LF quality essential forcrop tolerance
It is well known that uponcritical application conditions
and sensitive crop situations
the quality of LF influences
the crop tolerance preferably.
Pictures 1 and 2 show the LF
application in winter wheat at
BBCH stadium 32 – 37, thefirst with high the other one

with low surface tension. The
farmer can easily see this.
LF with high surface tension
creates big drops on the leaf.
With low surface tension
there is a complete coverage.

Picture 1: LF application with high surface tension (70 mN/m)

The application technology
should be chosen to adapt todifferent situation. The basic
rule is: The more sensitive
the crop surface is the useof coarse drops at reduced
spraying pressure should beused.

Picture 2: LF application with low surface tension (30 mN/m)APPLICATION OF LF IN A FUTURE
ORIENTATED AGRICULTURE
Guest comment of Mr. Fuchs, SKW, LF application research department

Risk of lower yields
can be eliminated
There have been a lot offield trials made with obvious
wrong application features.
The application with conventional flat fan nozzles on
negative conditions (morningdew, permanent rain before)caused in late stadium in
winter wheat leaf necrosis on
average of 13 %. The consequences of this necrosis werelower yields of 10 %.

This compared to test variances of LF applied by hose
drops or KAS granulates.
There was no difference in thelevel of raw protein. Nevertheless these losses of yield are
not acceptable. The relationof yield losses compared tothe scorched crop surface isrelatively small. Before every
application it is important to

identify the right application
technology for minimizing
scorching on the crop. Picture
3 shows that identical application conditions with the same
nozzles the quality of the LF
becomes important. The differences between the variances
are caused by the quality ofLF, in this case the physicalcharacteristic of surface tension. The LF with lower surface

LF also in the late stadium
between 32 – 49/51. Thereis no difference in the levelof raw protein or yield ofwinter wheat fertilized by
granulate or LF.

When the ears have appeared
the LF should be applied
only by hose drop or tube
drop systems. A combination
with pesticide application
is not possible under theseconditions.

tension scorched much moreleaves and the result werelower yield. Before buying theLF the quality characte­ristics
have to be checked.

Application at latestadium in winter grain –no problem
The technical development
has helped a lot to eliminate
any possible damage during
the last nitrogen application in
winter grain shortly before theears are appearing. Orificenozzles, FD nozzles, hose
drop or tube drop systems
offer the opportunity to apply

A couple of scientific researches support these facts.

Precise applicationon the target
LF offers a positive opportunity to fulfill the ever increasing
environmental consciousnessof the farmers and directives
from society. With extremely
precise calibration anddistribution a sustainableapplication in the field,
precisely ending at the fieldborder is achieved.

No uncontrolled application
can occur outside theboundaries of the field. New
technologies with N-sensors
or GPS connection realize an
application on partial areas
demand, this means precision
farming. Meanwhile there arenitrogen stabilized LF available which contribute to positiveenvironmental effects andavoid uncontrolled leaching.
FD nozzles are well preparedfor partial area application.
Changes in the pressure
don’t influence the droplet
size negatively; the extremely
coarse drops remain andare excellent for the crop
tolerance.

A higher pressure does notaffect the impact of the drop­lets when the droplets touchthe leaves. The droplets fall
down only by gravity andnot by the pressure of thesprayer.

Fertilizer systems
for the future

LF and precision
farming
This system allows varying
the application rate in arange of 500 % and thisat a constant low pressurelevel and precisely within
the working width.

Precision farming is theanswer to a lot of economical and environmental
questions.
One integral part of thisfuture agriculture will be
new technologies which
improve the efficiency ofnitrogen fertilizer including
precision farming via GPS.
Further new variances of N
fertilizer with more stabilized components support
modern agriculture, meanssaving costs and preserve
the environment. Balanced
nutrients reduce not only
the pollution of environment.

110

18105

17100

98.2

16159588.59085

12.7

12.8

PIASAN 28

LF with low
surface tension

60..7020..25

Leaf necrosis (%)

41313
1280

Surface-tension (mN/m)

14Crude protein (%)

Yield (dt/ha)

Spreaders for granulate
and sprayers for LF areable to apply on partial
areas in the field. Sprayers
are equipped with valves
which can adapt very fastand precise to the crop/
GPS map demand. For
instance Vario Select isable to add or reduce
number of nozzles without
modifying the pressure.

Picture 3: Relationship between surface extension of LF and the treatment level of the crop, yields and crude protein level,
average of 5 tests during 2004 – 2008.

This means also to utilize
full virility of fertilizer andto rescue the fertility of thesoil. LF is an excellent tool
especially due to precise
calibration and application.
As there is no significant
difference between thefertilizers variances it is
not the most importantquestion which N fertilizer
should be applied. Much
more important is tofollow up the different
application guide lines andto work on the conditionsof best practice.