Growers can begin to think further ahead to stem extension in oilseed rape once N applications have been completed. The stem extension phase of growth usually means nutrient requirements will increase.
Natalie Wood, Yara’s Agronomy Operations Manager, recommends that nutrient application for the best OSR yield are well considered. She said: “Once crops start the stem extension phase of growth, they require a lot of nutrients to keep up with their rapid rate of development.
“This of course means the requirement for major nutrients increases, but also the requirement for micronutrients as well. Think of the law of the minimum, where any limiting factor will affect the overall yield of the crop – micronutrients can be one of those limiting factors and cause major problems within the plant.”
Magnesium is one of the key nutrients required at the onset of stem extension in OSR. The micronutrient is a part of the chlorophyll and so plays a vital role in efficient photosynthesis.
“Think of all the chlorophyll production during the rapid phase of growth once the crops take off. Not having enough will mean less light capture and therefore it will affect crop development and eventually yield.”
Tissue testing enables growers to see which micronutrients are in the plant at that moment in time, however, there are other ways to protect crops from deficiencies. Ms Wood said: “If you can’t carry out a tissue test then you could apply a multi-nutrient product, such as Brassitrel Pro. It may not be as precise, but it will help by giving a crop the optimum amounts of key nutrients.”