Nitrogen (N)

Symptoms

• Deficiency symptoms first noticed in older and lower leaves.
• Newly produced leaves remains green & gives the plant flat top appearance.
• Midrib tissues become bright yellow
• Stunted growth

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.
• Frequent application of organic growth boosters is also beneficial.

Phosphorus (P)

Symptoms

• Older leaves become dull and assume a pale olive green color
• Premature desiccation of older leaves noticed in adult palms
• Deficiency Inhibit flowering & fruiting process
• Smaller & underdeveloped bunches are formed
• Trunks of affected palms become narrow and tapered.
• Reduced height, smaller trunk gives a pyramid shaped appearance to palms
• Palms exhibits shallow & poorly developed root system

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 and lower leaves
• Pale green spots on the pinnae of older fronds are noticed
• Exhibit smaller or narrower leaves
• White strip may develop on midrib of leaves
• Fruit exhibit uneven ripening & have lower fruit quality
• Fruit abscission is noticed
• In very severe cases, entire older fronds may dry up.

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.

Calcium (Ca)

Symptoms

• Deficiency is seen mainly in growing points, younger leaves and developing fruits
• Leaflets show browning/blackening at the tips.
• Fruit rot
• Stunted root growth

Management

• Analysis of pH in the soil
• If the soil is acidic, add 1 kg of lime per palm per year in one or two split doses.
• Dolomite can be substitute of lime
• High phosphorus levels leads to calcium deficiency.
• In alkaline soil application of Gypsum is preferable

Magnesium (Mg)

Symptoms

• Deficiency is seen first in the bottom leaves
• Mature fronds show a yellow green chlorosis
• Starting from tips & margins progressing towards inwards.
• Necrotic patches on margins are noticed
• Reduce leaf size & abnomal leaf growth
• Poor fruit set, reduced size & uneven ripening of fruit

Management

• Do the soil analysis and confirm the deficiency.
• Addition of Magnesium sulphate (400 gram /palm 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

• Symptoms first appear in the upper and younger leaves.
• Chlorosis followed by general yellowing.
• Yellowing can be more prominent between veins giving a, mottled appearance
• Deficiency affects oil yield , fruit development
• Affected plants show stunted growth.

Management

• Application of sulfur-containing fertilisers, such as Factamfos, Ammonium sulphate, Single superphosphate, etc., reduces the deficiency.
• In sulphur deficient soils , apply sulphur dust (125 gram per palm 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

Copper (Cu)

Symptoms

• Chlorosis starts from tips & margins of leaves spreading towards centre
• Necrosis appear on leaves & eventually lead to leaf drops.
• Necrosis extends to stem & branches causing dieback.
• Leaf may appear small narrow elongated with twisted wavy margins
• At severe deficiency leaves become almost white
• Tree appears weak with short internodes.
• Fruits may exhibit uneven ripening, smaller fruits set

Iron (Fe)

Symptoms

• Symptoms appear first on the youngest fronds, which appear droopy
• Interveinal chlorosis observed on young leaves may progress toward older
• Affected leaves may turn white or pale yellow colour giving them a bleached appearance
• Deficient leaves may appear smaller in size & irregular in shapes ,
• Uneven ripening & smaller fruits set
• Stunted growth with shorter internodes

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 (75 gram/palm or 6 kg/ acre) into the deficient soils

Manganese (Mn)

Symptoms

• Symptoms first appear on those leaves just reaching their full size.
• Chlorosis starts from margins
• Necrosis also extends to leaf margins
• Leaf tissues may dry out, die & eventually lead to lead drop
• Lower fruit set

Management

• Soil Analysis
• Application of Manganese Sulphate ( 5 gram per litre of water) as foliar spray

Zinc (Zn)

Symptoms

• Interveinal chlorosis
• Deficiency appears as small, narrow white streaks on lower and mid-crown fronds
• Blotchy leaf symptoms has also been identified

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 (100 gm /palm 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.