So when the soil become deficient in available nitrogen, nitrogen from lower leaves will get transferred to growing points.
Hence, deficiency symptoms will be first noticed in older and lower leaves.
The initial symptoms will be pale green to light green colour change on leaves.
This later change to yellowing of the older leaves with red tints and later necrosis.
The growth of the affected plants will be stunted.
Management
For determining the severity of the deficiency, soil analysis has to be done
Application of quick releasing nitrogen fertilizer like urea, according to the results of the soil test.
Apply urea as a foliar spray (10 gram per litre of water) once every 15 days
Frequent application of organic growth boosters is also beneficial
Phosphorus (P)
Symptoms
In deficient situations, the root growth will be affected.
This results in poor uptake of needed nutrients.
The deficiency symptoms will be first noticed in older and lower leaves.
The older leaves strong purple tints and die off early.
The affected plants will show stunted growth.
Management
Ensure that recommended amount of fertilizer is applied on regular time.
For determining the severity of the deficiency, soil analysis is to be done
Use fertilizers such as single superphosphate for quick correction or bone meal or rock phosphate for long-term correction.
In the pH range of 6.2-7.0, phosphorus is readily absorbed by the roots.
Addition of biofertilizers including phosphorus solubilizing bacteria along with organic manure helps to increase the availability of phosphorus
Potassium (K)
Symptoms
Potassium is a highly mobile element in plant.
So the deficiency symptoms will be first noticed in older and lower leaves.
The symptom starts as marginal scorching of older leaves followed by general browning and collapse.
Growth stops and leaves curl backward.
Management
In the pH range of above 6, potassium is readily available.
Maintain pH by addition of lime/dolomite
Improve the soil fertility by adding organic matter and wood ash.
For determining the severity of the deficiency, soil analysis is to be done
Use Muriate of Potash (MOP) according to the results of the soil test. Split application is preferable.
Apply foliar sprays of Sulphate of Potash (SOP) (10 g/litre of water) and wetting agents in the morning as an immediate remedy
Calcium (Ca)
Symptoms
Calcium is an immobile element in plant.
Hence, calcium deficiency is seen mainly in growing points, younger leaves and developing fruits.
The initial symptom will be browning and necrosis of the growing tips of roots and leaves.
The internodal length becomes reduced and leaves become rosetting.
The edges of the leaves will look ragged and often brittle.
The petiole of the affected plant collapse and as a result the leaf withers.
Management
Do the soil analysis
Check the pH of the soil. If the soil is extremely acidic (pH between 3.5 and 4.5), apply lime (3.4 kg/cent in two split doses). And in areas of moderate acidity (pH between 5.5 and 6), apply lime 1 kg/cent.
High phosphorus levels lead to calcium deficiency.
In alkaline soil application of Gypsum is preferable
Boron is needed for calcium utilization.
So, a boron deficiency can also lead to calcium deficiency.
Magnesium (Mg)
Symptoms
The symptoms of magnesium deficiency are seen first in the bottom leaves.
As the deficiency becomes more acute, the symptoms progress up the plant.
The predominant symptom is dark green veins with yellow areas between the veins (interveinal chlorosis).
Chlorotic leaves generally turn red and then develop spotted necrotic areas.
Management
Do the soil analysis and confirm the deficiency.
Addition of Magnesium sulphate (32 kg/ acre) in bands near plants.
Long-term usage of dolomite will reduce magnesium deficiency
Magnesium and potassium fertilizers should not be applied together
Sulphur(S)
Symptoms
Sulfur is a relatively immobile element in plants.
So deficiency symptoms first appear in the upper and younger leaves.
The symptoms are chlorosis followed by general yellowing.
An acute sulfur deficiency causes the entire plant to turn yellow.
The affected plants show stunted growth.
Management
Application of sulphur-containing fertilisers, such as Factamfos, Ammonium sulphate, Single superphosphate, etc., reduces the deficiency.
In sulphur deficient soils, apply sulphur dust (10 kg/acre).
Deficiency in alkaline soil can be reduced by application of gypsum
Addition of organic material improves sulphur availability in the soil
Burning of organic waste leads to sulphur deficiency
Boron (B)
Symptoms
Boron is an immobile element in plant.
Hence, boron deficiency is seen mainly in growing points, younger leaves and developing fruits.
Growing point may die.
Growth of young leaves will be restricted giving a rosette effect to the plant.
Older leaves show orange tint discolouration.
Management
Analysis of soil to confirm the deficiency.
Application of borax (4 kg/ acre) into the soil
Addition of borax (1 gram / litre of water) as foliar spray
Avoid the combined application of Boron and calcium.
Application of borax with ammonium fertilizers should be avoided.
