Wheat

A balanced crop fertiliser programme including all macro and micro nutrients is essential to achieve high yields. The main components of wheat yield are grain numbers and individual grain weight. Both of these components are strongly influenced by nutrition.

The key to achieving high wheat yields, having established the correct canopy structure, is to maintain the green area right through to the final grain filling period, capturing as much of the incident light as possible and converting it to yield.

The number of leaves determines the size of the crop canopy and its photosynthetic potential. The number of shoots and how many of these survive through to harvest also determines the number of ears at harvest and so the potential yield.

Wheat grain size is strongly influenced by plant nutrition particularly during the important grain filling period. Nitrogen, phosphate, potassium, magnesium and zinc are particularly important.

The grain number is itself a function of the number of fertile shoots per unit area and the number of grains per ear. The grower therefore needs to consider how nutrition can have an impact on the grain numbers per ear.

Crop nutrition can have a great impact on the quality of the harvested grain and fertiliser applications should be planned to help achieve the highest value for the grain often through a combination of specifications.

Nitrogen and sulphur both influence grain protein content and quality. Nitrogen should be applied when the plant can still incorporate the nitrogen into its grain, and sulphur levels need to be adequate to ensure this does not limit nitrogen use.

The Hagberg falling number is used to determine suitability of wheat for bread making, with higher numbers preferred by millers. Effective crop nutrition management particularly of nitrogen and potassium can help increase the Hagberg falling numbers.

Grain specific weight is a measure of the density of the grain. Specific weight is predominantly a genetic trait of varieties, but poor crop nutrition and application can reduce specific weight.

When wheat is destined for biofuel production, the yield of ethanol is a key component to consider. Varietal choice is an important consideration with those that are soft wheat types tending to give higher ethanol yields.

Plant nutrients are predominantly associated with increasing yield and quality through ensuring no mineral deficiency is restricting growth and development. However, a well balanced fertiliser programme will help the plant protect itself from disease.