Page 25 - AWA Vol.42-No.1 issue

CROP PROTECTION

Early topdressing in cereals is a key tool

In recent years, cereal fertilization planning has been
clearly influenced by two key factors: the high price of fer-
tilizers and the low value of the harvest. This combination
has led many farmers to forgo base fertilization in order
to reduce initial investment and minimize economic risks.
At Herogra, we do not consider this practice to be a suit-
able agronomic recommendation. The absence of base
fertilization can have significant consequences for crop
development, compromising its productivity from the ear-
liest stages of the cycle.
What happens when there is no fund subscriber
When cereal crops begin their development without
base fertilization, nutrient availability is very limited. In es.
cold soils, with low mineralization or little residual fertil-
ity, this situation usually results in a noticeable delay in Early topdressing fertilization strategies
initial growth. Herogra Fertilizantes, true to its commitment to offer-
This early delay is not a minor problem: it directly af- ing highly effective nutritional solutions, provides farm-
fects root system development, the number of suckers, ers with "tailor-made" fertilizers, adapted to the specific
and the crop's ability to reach its full yield potential. For needs of each crop, soil, environmental conditions and
this reason, when base fertilization is not carried out, early application system.
topdressing ceases to be an option and becomes the only These fertilizers may incorporate inhibitors that allow the
agronomic tool capable of compensating for this initial nu- use of optimized and stabilized nitrogen under the follow-
tritional deficit. ing ranges:
Early coverage: what it is and why it works • NEO : fertilizers with urease inhibitor.
Early topdressing involves applying fertilizer during the • HEROSOL GOLD : fertilizers with nitrification inhibitor.
initial stages of crop development, typically between the
3-4 leaf stage and the beginning of tillering. When prop- Practical example in wheat without base fertilization
erly applied, it can effectively compensate for the lack of The following are two possible strategies for a wheat
base fertilization, especially in fields with low seeding crop with a yield potential of 4,000 kg/ha and a soil of me-
rates. dium fertility:
A properly planned early cover crop benefits: Strategy 1: Early single cover
• A rapid increase in vegetative vigor. Recommended when the crop shows uniform emergence
• Stimulating tillering is key to determining the final num- and the weather forecasts are stable.
ber of ears of grain. • Application: 450 kg/ha of HEROSOL ORO 27+6+6+5 SO₃
• A more active root system and better soil exploration. between early tillering and full tillering.
• Greater crop resilience to water or heat stress. Strategy 2: Two split topdressings
Agronomic factors that influence its effectiveness This strategy allows for better nitrogen distribution, re-
For early cover cropping to be truly effective, it is essen- duces losses and ensures nutrition in critical phases such
tial to consider several key factors: as heading and grain filling.
1. Phenological stage of the crop. • First topdressing (3–5 leaves / start of tillering):
The timing of application is crucial. A late application 150 kg/ha of NEO 23+5+11+27 SO₃ .
limits the ability to produce suckers, while applying too (The nitrogen dose will be higher the lower the plant
early can increase the risk of losses due to leaching if density, the later the vegetation or the earlier the variety).
heavy rains occur.
2. Plant Density. • Second cover crop (beginning of stem elongation):
220 kg/ha of NEO 35 (S) Special Cereal.
In situations of irregular emergence or low density, the
response to early nitrogen application is usually greater. Conclusion
Trials in wheat confirm that, in these cases, early topdress- When no base fertilization has been carried out, early
ing becomes even more important. topdressing represents the only opportunity to properly
3. Fertilizer Composition guide the development of the crop before it is too late.
Although nitrogen is the main nutrient, other elements At Herogra, we recommend planning this intervention
such as sulfur, magnesium or available phosphorus can precisely, adjusting the dosage, nitrogen form, and nutri-
be determining factors, especially in poor or cold soils. ent combination to the plant density, soil type, and specific
4. Climate and soil type conditions of each growing season. Only in this way will
In areas with irregular rainfall or light soils, the use of the cereal reach stem elongation with a solid, balanced
controlled-release nitrogen or nitrogen stabilized with in- structure capable of expressing its maximum productive
hibitors improves fertilization efficiency and reduces loss- potential. Circle 25 on enquiry card
Vol. 42 No. 1 23