Form
Taken up as both Phosphate, HPO4, and Phosphite H2PO3- Phosphorous (P) is essential for energy transfer, cell division and the development of root and shoot systems.
Function
Phosphorous promotes root activity, affecting the uptake of nutrients and water, the formation of sugars and the development of both flowers and fruit. In addition, Phosphorous plays a central role in maintaining plant health and in stimulating the activity of beneficial microbes in the root zone. Low Phosphorous status can result in slow growth rates, poor fruit set and low Brix levels.
Early symptoms of phosphorous deficiency (right), note severe stunting and deeper green colour of foliage.
Symptoms
Phosphorous stress is typically seen in younger stem and leaf tissue as a distinct purple or bronze chlorosis. Plants tend to be slow growing, stunted, with poor root mass, flower set and fruit development.
Phosphorous Deficiency in ‘D’Amjou’ pear.
Significance
Phosphorous stress affects the early stages of development, during which the plant is setting genetic yield potential. In addition, tolerance to biotic/abiotic factors will be poor, increasing risk of drought/heat stress and reducing disease resistance mechanisms. Phosphorous stress is often worse in alkaline soils and P-fixing soils rich in calcium, magnesium, iron or aluminium.
Phosphorous deficiency in potato, note mild to severe leaf roll and grey green lower leaf surface.
Actions
Check soil status and correct if necessary. Place and protect Phosphorus fertilisers. Foliar treatment at the onset of active growth can be very effective. Routine foliar Phosphite can have a major impact on promoting plant health. We have a wide range of products containing phosphorous, including:
Suspension fertilizer containing highly available phosphorous, as phosphite and phosphate, with trace elements
Highly concentrated NPK suspension fertilizer with emphasis on phosphorous, also contains potassium, nitrogen, magnesium & micro-nutrients
A suspension fertilizer containing phosphite, phosphorous and potassium, with copper, zinc and manganese
For more information and advice on any of our products please contact us: enquiriesagrifluids@omex.com