Adequate nutrition including both macro and micronutrients has always been important for autumn-sown crops, not just to ensure successful establishment but to set the ultimate yield potential of the crop, so micronutrients should be an integral part of any crop nutrition programme.
2020 trial results have again confirmed the extra yield that can be obtained from the inclusion of key micronutrients in your nutrient strategy. For example, on winter wheat over 0.5 t/ha of extra yield was achieved from an application of copper. This was on a site that delivered good yields at approximately 9 t/ha where no micronutrients were applied. On oilseed an extra yield of 0.66 t/ha was observed following the application of micronutrients in Brassitrel Pro.
A deficiency of any single nutrient is enough to limit yield
Over the year’s trials have also taught us the importance of getting these micronutrients on at the key timings, before any deficiency starts to appear. A preferable mindset is to think about ensuring sufficiency of supply. This is where the importance of historic farm data comes into its own, enabling proactive decisions to be made. If such data is not available, an alternative proactive approach can be taken by using crop-specific products that have been designed to deliver the key nutrients for crop growth and development.
You may ask how do we know what are the key nutrients for each crop? The answer here again lies with research data and knowledge that has been conducted to identify them. Yara, through its research facilities in Pocklington, York, runs a screening process through nutrient specific trials to priorities nutrients according to their impact on crop growth and development. Once these are established then crop-specific products can be formulated to deliver enough quantities of these specific nutrients. Crop specific products are an ideal way of starting your micronutrient strategy in the autumn, especially with the earlier drilled crops (e.g. wheat and oilseed) that will be starting to develop those all-important yield components during the autumn/winter months.
For the oilseed crop to be resilient and come through the winter months the target should be to have 6 - 8 true-leaves, with a root head diameter of >5 mm and a shoot length of around 20 mm. During the autumn the potential number of flowering branches is also set with flower initiation taking place from November. With so much of the yield potential being generated during this period, the autumn crop nutrition plan is critical. YaraVita Brassitrel Pro with its combination of nutrients including Boron is an ideal solution for this growth period. Annual field trials continue to demonstrate the value of this product with on average an extra 0.33 t/ha yield (2016-2020). The 2020 response was even greater at 0.66 t/ha when applied sequentially with 3 l/ha in the autumn and spring.
Likewise, winter wheat initiates many of the components of yield during autumn growth, especially with those early (September) drilled crops. This again is the reason why trials evidence supports the application of essential micronutrients during this ‘foundation’ phase. YaraVita Gramitrel is the crop-specific solution designed for winter cereals, with the optimum application timing being a sequential, autumn followed by spring program. The autumn application should be timed from 2 true leaves onwards. Long term trials have shown that this application can deliver up to a 0.33 t/ha more crop yield. Not only can you anticipate extra yield, but also a healthy crop. With this product containing zinc and manganese, the developing plants will be more resilient to overwinter disease, going into the spring with reduced disease levels. These observations have been reported by agronomists on a number of occasions since the product was introduced into our trials program in 2015. It is also worth noting that YaraVita Gramitrel was the micronutrient product that helped deliver the World Record wheat crop in 2020.
Micronutrients are not just for high yield potential crops
Are micronutrients only worth investing in on high yielding crops? Is another question we often get. Whether a wheat crop is 5 t/ha or 17 t/ha, 0.33 t/ha is the same value irrespective of yield. There is an argument that every extra bit of yield that can be achieved on a low yielding crop helps to spread the fixed costs that are higher per tonne on a poor crop!
The following crop specific micronutrient products are recommended for autumn and spring application