DDCROP 15-7-12

Autumn, Spring

• Avoid applications on chloride sensitive crops

• Nitrogen is always the nutrient in highest demand by plants, due to the greater content of nitrogen present on a dry weight basis in comparison to any other nutrient.
• Nitrogen is a primary component of amino acids which are the building blocks of proteins. Thus, by adding nitrogen to soil the protein content in plants is increased.
• Nitrogen is part of the chlorophyll molecule, and a part of numerous enzymes and coenzymes. Chlorophyll is responsible for photosynthesis, where sunlight is absorbed and stored in the plant as sugars and proteins.
• Therefore, nitrogen is an integral part of photosynthesis.
• Signs of nitrogen deficiency – reduced plant growth, yellowing of the leaf, early crop maturing.

• The most important role of phosphorus is the storage and transfer of energy that is generated through photosynthesis along with the metabolism of carbohydrates.
• Phosphorus is an essential compound of Adenosine Triphosphate (ADP), the energising component driving plant development.
• Phosphorus deficiency has a huge impact on plant growth and reproduction, reducing the plant processes noted below.
• Processes aided by phosphorus:
  • Large root growth
  • Early formation of plant shoots
  • Improved stalk and stem strength in crops
  • Improved fruit, vegetable, and grain quality
  • Seed formation
  • Resistance to moisture and colder temperatures

• The main role played by potassium in plants is the balancing of negative charge from anions such as nitrate and sulphate.
• Potassium is required for protein and starch synthesis and is involved in activating enzyme systems within the plant.
• Potassium enhances plant quality through shape, size, vigour, and strength.
• Grasses and clover compete for potassium, therefore low potassium pasture has no clover present and high potassium pasture has a strong presence of both grass and clover.

• Sulphur is essential in forming plant protein as it is present in cysteine and methionine, two vital amino acids involved in protein synthesis.
• Key component of coenzymes and vitamins, involved in energy transfer and lipid synthesis.
• Some sulphur compounds are responsible for the taste and smell of plants, like onions.
• Sulphur amino acids are at high levels in animal fibres, therefore sufficient sulphur is required for good wool production.
• Promotes nodule formation in legumes
• Signs of sulphur deficiency – light green to yellowish coloured young leaves, reduced plant growth rates, plants that are short, small and slender.

• Calcium is vital for both plant and animal growth
• An essential part of the plant cell wall and membranes, aiding in plant structure and stability
• Earthworm activity is increased by the presence of calcium in the soil profile, therefore natural soil aeration is also increased
• Boosts soil microorganism activity, improving soil structure
• Calcium deficiency affects fruit crop quality and growth, and limits biological activity
• Calcium and magnesium work in synergy to promote stable soil structure
• Involved in the signalling of the availability of other nutrients (e.g. potassium), through its secondary messenger characteristics
• Assists in protecting the plant from biotic stresses

• Critical for both plant and animal growth, with deficiencies noticed in the animal before the plant
• Assists in plant defence processes against abiotic stresses
• Magnesium is the central core of the chlorophyll molecule – therefore its presence is vital for photosynthesis
• Low levels of plant intake can lead to hypomagnesaemia in livestock, especially during the winter/early spring months
• Magnesium is very mobile in the plant and aids in numerous plant processes such as enzyme activation and phosphate metabolism, as it acts as a phosphorus carrier
• Magnesium and calcium working in synergy to promote stable soil structure