To achieve high barley yields, having established the correct canopy structure, it is important to maintain the green leaf area right through to the final grain filling period, capturing as much of the incident light as possible and converting it to yield
Nitrogen directly affects leaf chlorophyll content
The nutrients nitrogen, potassium and magnesium are of particular importance in maintaining a green leaf canopy.
Chlorophyll is a nitrogen and magnesium rich protein that gives the plant its green colour and is central to efficient photosynthesis. The relationship between leaf chlorophyll content and nitrogen is well proven with more chlorophyll as the leaf percentage of nitrogen increases.
Magnesium helps keep the leaf canopy greener for longer
Magnesium is the central component of chlorophyll linked to four nitrogen molecules. The magnesium level is also therefore important in maintaining the green leaf canopy.
Potassium maintains straw stiffness and reduces lodging
As well as the canopy greenness, it is also important to ensure that the structure and architecture is maintained further improving the efficiency of the crop to capture light and convert it to yield. The more, larger cells produced by the nitrogen means more water in the plant which then requires more potassium. Potassium plays a very important role in maintaining cell turgidity and strength as well as nutrient movement around the plant. Inadequate supplies of potassium can lead to premature wilting and a lodged canopy. Straw deficient in potassium is more brittle increasing the risk of lodging / brackling that dramatically reduces both yield and quality.