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Wheat monitoring gives good results

Excellent results were obtained this past season with the monitoring of wheat by means of leaf analyses throughout the growth season.

Leaf samples were taken from seed maize, the previous crop, at the client, Andries Beyers from Beyplus Farming. From the results of these leaf analyses as well as DRIS* analysis results on the previous crop, it was determined that potassium was the element most likely to limit yield.

Graph 1: Results from leaf analyses obtained from the previous seed maize.
Graph 1: Results from leaf analyses obtained from the previous seed maize.

* DRIS = Diagnosis and Recommendation Integrated System (Ratio analysis of plant analysis values)

Graph 2: DRIS analysis results from the previous crop
In-season sap sodium levels in Australian vines for soils treated with polyacrylamides.

The above results showed clearly that potassium levels on the leaf analysis were very low. The DRIS index also pointed K out as the most limiting nutrient.

The Mg/K ratio on the soil analyses was 9:1, while the ideal is between 3 and 4. This confirmed that the high magnesium levels in the soil further inhibited the uptake of potassium. The DRIS graph clearly shows how high the magnesium levels were.

From the previous season’s results we could see that extra attention had to be given to potassium fertilization on the next wheat crop.

The agronomist, Jannie Peyper, decided to use 13:7:10 (30) + S at planting to ensure that sufficient K was applied early on and the additional potassium was applied at topdressing.

Leaf analyses taken on the wheat a second time showed that the K was sufficient and in balance with the rest of the macronutrients.

In-season sap sodium levels in Australian vines for soils treated with polyacrylamides.
Graph 3: Second leaf analysis after application of fertilizer.

Based on the leaf analyses, which shows that copper (Cu) was also low, it was decided to apply additional Speciality products through the pivot. MAP39 was applied at 5 kg/ha, ORGANOCELL™ at 0.5 litres/ha, Solubor® at 3 kg/ha and OMNIGREEN™ at 2 kg/ha.

The yield target for the wheat was 7 t/ha. The extra potassium and Speciality products made it possible to push the total on the farm Houthaalboom to 7.5 t/ha. The farm Hendriksdal had an average of 8 t/ha over all the hectares.

In effect it was possible to harvest between half a tonne to one tonne above the yield target, just by addressing those elements most likely to limit yield.

Photo 1: Wheat in flag leaf stage. The first ears are starting to emerge.
Photo 1: Wheat in flag leaf stage. The first ears are starting to emerge.

Photo 2: The agent, Hannes van Rensburg (left), and the farm foreman, Bokser (right) with the young wheat.
Photo 2: The agent, Hannes van Rensburg (left), and the farm foreman, Bokser (right) with the young wheat.

Photo 3: Hannes van Rensburg among the grain-filled wheat.
Photo 3: Hannes van Rensburg among the grain-filled wheat.

Photo 4: Jannie Peyper (agronomist) shows how well the wheat responded.
Photo 4: Jannie Peyper (agronomist) shows how well the wheat responded.

Agriculture: Jannie Peyper (083 288 7131)
Agent: Hannes van Rensburg (082 578 2754)