Pale or yellow color from starts from lower leaves & progresses to upper side leaves of the plant
Reddish tints gradually observed on leaf margins progresses towards the midrib or central vein.
Overall growth is markedly reduced.
Deficiency results in reduction of rhizome yield
Delayed maturity
Poor root development
Reduced leaf size.
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
Purple coloration appears particularly on the underside of leaves.
Poor root development.
Yellowing starts from leaf tips to base in older leaves
The affected plants tend to be dark green color than healthy plants.
Small stunted rhizomes are developed
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 6.5-7.5, 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
Deficiency symptoms will be first noticed in older leaves
Marginal chlorosis of older leaves
Marginal burning or scorching of leaves
Shortened internodes
Necrotic (dead) spots in the leaf
Wilting tendency of plants
Stunted growth of plants
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 gm/liter of water) and wetting agents in the morning as an immediate remedy
Calcium (Ca)
Symptoms
Deficiency is seen mainly in growing points and younger leaves.
Leaves appear crinkled twisted or have irregular growth patterns
Edges of leaf may exhibit necrois
Small & less vigour of the plant results in stunted growth
Roots of affected plants tend to be stunted, malformed & decay
Management
Analysis of pH in the soil
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 of 40 m2 in two split doses). And in areas of moderate acidity (pH between 5.5 and 6), apply lime (1 kg/cent of 40 m2).
High phosphorus levels leads 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
Interveinal chlorosis between the veins whereas the veins remains green & progress upwards
plants have brown spots and necrosis between veins starts from tips or the edges of leaves
Leaf deformation such as curling & cupping were noticed
Deficiency may cause death of growing point
Poor flowering
leaf has become chlorotic.
Stunted growth of the plant with under developed rhizomes
Older leaves may develop triangular arrowhead at the base of the leaf, near the stalk.
Management
Do the soil analysis and confirm the deficiency.
Addition of Magnesium sulphate (320 gram /plant or 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
Chlorosis followed by general yellowing
Simultaneous loss of green color from both the veins and the areas between the veins.
Thin & weak stems leads to bending or lodging
Plant growth is stunted & appears smaller including above & below ground rhizome developmemt
Deficiency Delays maturity & takes longer time for harvest
Develops necrotis spots on deficient leaves which appear as brown/black patches
Deficiency reduces aroma & flavour
Management
Application of sulfur-containing fertilisers, such as Factamfos, Ammonium sulphate, Single superphosphate, etc., reduces the deficiency.
In sulphur deficient soils , apply sulphur dust (100 gram per plant or 10 kilogrammes per 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
Tips of young leaves become white & rolled
Growing point of plant dies
Plant exhibits small & stunted growth
Leaf deformaction such as curling, wrinkled & reduced size
Necrotic spots on leaves appear as brown or black which starts at tips, form patches & progresses inwards
Flowers may be malformed
Deficient plants exhibIt poor seed development
Management
Analysis of soil to confirm the deficiency.
Application of borax (40 gram /plant or 4 kg/ acre) into the soil
Addition of borax (1 gram / liter of water) as foliar spray .
Avoid the combined application of Boron and calcium.
Application of borax with ammonium fertilizers should be avoided.
Iron (Fe)
Symptoms
Symptoms noticed first in the young leaves of plants.
Intreveinal chlorosis between the veins where as veins remains green
Yellowing starts between veins lead to pale white or bleached appearance
Reduced flowering & under developed rhizomes are formed
Deficiency resembles symptoms of Sulphur deficient plants
Management
Iron content in Kerala soils is often high. So, get a soil test to determine the reason for the problem
Low potassium levels leads to iron deficiency
Addition of Ferrous Sulphate (60 gram/plant or 6 kg/ acre) into the deficient soils.
Manganese (Mn)
Symptoms
Interveinal chlorosis of young leaves
Leaves appear mottled or marbled appearance with yellow patches between the veins.
Noticed mainly on younger leaves
Margins may curl upward or inward
Stunted growth with reduced flowering & under developed rhizomes are noticed
Management
Soil Analysis
Application of Manganese Sulphate (5 gram per litre of water) as foliar spray
Zinc (Zn)
Symptoms
Interveinal chlorosis where the yellowing seen between veins
Distorted leaf shape, reduced leaf size,puckered or rosette like appearance are the symptoms of the deficiency
Delayed flowering
Less branched , Shorter roots, & overall reduced growth of the plant may occur
Deficiency cause bunching of leaves at the top of the plant.
Management
The optimal pH range for zinc availability is 5 to 7.5.
Confirm deficiencies by doing soil testing.
Apply zinc sulphate to deficient soils (800 g /plant or 8 kg/ acre)
Avoid the application of Zinc and phosphate fertilizers at the same time
In severe cases, foliar spraying of Zinc sulphate (2 gram/liter of water) with Calcium carbonate (2.5 gram/liter of water) can be advocated in morning hours.
