Phosphorus

Question 1

Phosphorus

Rôle 1

Answer 1

Component of nucleic acids which regulates protein synthesis

Question 2

Phosphorus

rôle 2

Answer 2

Required for production of ATP.

Question 3

Phosphorus

Rôle 3

Answer 3

Required for energy transfer in metabolism.

Question 4

Phosphorus

Rôle 4

Answer 4

Used in development of new plant tissue eg. Stimulation of tillering in roots.

Question 5

Improving phosphorus in soil

Inorganic fertiliser

Answer 5

Superphosphate

Question 6

Improving phosphorus levels in soil

Organic

Answer 6

Add slow release organic fertiliser eg bone meal

Question 7

Improving phosphorus levels in soil

Cultural means

Answer 7

Add organic matter - phosphorus released on decomposition or mineralization of organic matter.

Keep soil neutral pH - fixed insoluble phosphate compounds form in low and high pH range making phosphorus unavailable to plants.

Question 8

Use of mycorrhizal fungi to improve phosphorus levels to soil.

Answer 8

Mycorrhizal fungi form network on hyphae that forage over a greater area than plant roots alone can - greater uptake of phosphorus.

Question 9

How phosphorus can be lost from soil

Answer 9

Leaching

Harvesting of crops

Question 10

Symptoms of phosphorus deficiency

Answer 10

Mobile, affects older leaves first.

Purplish colour in seedling, then yellowing.
Cell division retarded.
Stunted, weak growth.
Poor root development, storage doesn’t form.
Poor flower and fruit formation.
Small, bronze, purple leaves.

Question 11

Phosphorous deficiency

Cause

Answer 11

Caused by poor root activity, large, slow moving ion affected by low soil temp and O2 levels.

Fixation of soluble phosphate into insoluble aluminum phosphate and iron phosphate can cause phosphorus to become unavailable.