Tomato - Deformation
Symptoms
Phosphorus deficiency causes small and rigid leaves, the plant habitus is very erect. Growth is sparse, thus the plant shows a spindly appearence.
Total height is almost normal.
The bottom leaves show interveinal chloroses and necrotic leaflets.
Causes
Phosphorus deficiency
Leaves with P deficiency are usually dark green to bluish green in color. However, in the present case, there is no dark discoloration detectable.
Tomato - Discolouration
Symptoms
Beginning from the margin, the surface or undersurface of older leaves becomes dark green or purplish red at severe phosphorus deficiency.
Causes
Phosphorus deficiency on the leaf.
Similar symptoms can be found when the tomato plants are grown at too low temperatures since phosphorus uptake is inhibited under these conditions.
Tomato - Chlorosis
Symptoms
In some cultivars, the phosphorus deficiency appears as small brown dots which develop interveinally on the lower leaves.
Starting from the leaf margin, chlorotic and subsequently necrotic areas progress.
In other cases, the surface or undersurface of older leaves becomes dark green or purplish red at severe phosphorus deficiency.
Causes
Phosphorus deficiency on the leaf
Tomato - Chlorosis
Symptoms
In some cultivars, the phosphorus deficiency appears as small brown dots which develop interveinally on the lower leaves.
Additionally, starting from the leaf margin, chlorotic and subsequently necrotic areas progress. The necroses may have a brown or a dull, dark olive, colour.
Causes
Phosphorus deficiency on the leaf
Phosphorus deficiency made worse by
- Acidic or very alkaline (calcareaus) soils
- Low organic matter
- Cold or wet conditions
- Crops with a poorly developed root system
- Soils with low P reserves
- Soils with a high phosphate capacity
- Iron rich soils
Phosphorus is important for
- Energy transfer
- Nucleic acid formation
- Protein synthesis
- Cell membrane component
- Carbohydrate metabolism
