Coconut (Cocos nucifera); Palmae

Soil- 

  •  Red sandy loam, laterite and alluvial soils are suitable.
  • Heavy, imperfectly drained soil is unsuitable.

Climate – 

  • It is essentially a tropical plant, growing most!y between 20° N and 20° S latitudes.
  • The ideal temperature for coconut growth and yield is 27 ± 5° C and humidity > 60 per cent.
  • June-July, December – January.
  • The planting can also be taken up in other seasons wherever irrigation and drainage facilities are available.
  • Adopt a spacing of 25′ x 25′ (7.5 x 7.5 m) with 175 plants/ha.
  • For planting in field border as a single row, adopt 20′ spacing between plants.
  • Dig pit size with 3‘ x 3′ x 3
  • Fill the pit to a height of two feet (60 cm) FYM, red earth and sand mixed in equal proportions.
  • At the center of the pit, remove the soil mixture and plant the seedling after removing all the roots.
  • Press the soil well around the seedling and provide the seedling with shade by using plaited coconut leaves or palm leaves.
  • Keep the pits free from weeds.
  • Remove soil covering the collar region.
  • As the seedlings grow and form stem, fill up the pits gradually by cutting the sides.

MonthsNormal condition
(for best yield)
Moderate water scarcity conditionSevere water scarcity condition
A. Drip irrigation
 February to May65 lit / day45 lit/ day22 lit / day
 January, August and   
 September
55 lit / day35 lit / day18 lit/day
 June and July,  
 October to December
45 lit / day30 lit/ day15 lit / day
B. Basin irrigation
 February to May410 lit / 6 days * 
 January, August and 
 September
410 lit /7 days*
 June and July,  
 October to December
410 lit /9 days*

Eastern region 

MonthsNormal condition
(for best yield)
Moderate water scarcity conditionSevere water scarcity condition
A. Drip irrigation
  March – September80 lit / day55 lit / day27 lit/day
 October – February50 lit / day35 lit/ day18 lit /day
B. Basin irrigation
 March – September410 lit / 5 days* 
 October – February410 lit /8 days*
  • * Quantity of water to be applied in the basin. Add 30-40 % of the above quantity of water (135 -165 liters /palm) to meet the conveyance loss.
  • For drip irrigation, open four pits size of 30 x 30 x 30 cm opposite to each other at one meter distance from the trunk.
  • Place 40 cm long PVC conduit pipe (16 mm) in a slanting position in each pit and place the drippers inside the conduit tube and allow the water to drip 30 cm below the soil surface.
  • Fill the pits with coir pith to prevent evaporation.
    In the first year, irrigate on alternate days and from the second year to the time of maturity irrigate twice in a week based on the water requirement.

1.Mulching with coconut husks/leaves/coir pith

Coconut husk mulch | India | Cyndy Sims Parr | Flickr

  • Apply coconut husks with convex surface facing upwards (100 Nos.) or dried coconut leaves (15 Nos) or coir pith up to a height of 10 cm in the basin of 1.8 m radius around the palms as mulch for soil moisture conservation particularly during summer season.
    2.Burial of coconut husk or coir pith
  • Husk burial can be done in coconut basins or in the interspaces to overcome drought and button shedding.
  • Bury husks @ 100 Nos. with concave surface facing upwards or 25 kg of coir pith/palm in circular trenches, dug 30 cm width and 60 cm depth at 1.5 meters radius.
  • The husk can be also buried in the trenches at a distance of 3 m from the palm with a size of 45 cm deep and 150 cm width in between two rows of coconut.
  • The soaking of the coconut husk or coir pith as the case may be preserves the monsoon rains.
  • Manuring
  • From 5th year onwards, apply 50 kg of FYM or compost or green manure.1.3 kg Urea (560 g N), 2.0 kg Superphosphate (320 g P2O5) and 2.0 kg Muriate of potash (1200 g K2O) in two equal splits during June – July and December – January.
  • Apply manures and fertilizers in circular basins of 1.8 m from the base of the palm, incorporate and irrigate.
  • During 2nd, 3rd and 4th year ¼, ½ and ¾ doses of the above fertilizer schedule should be adopted respectively.
  • Sufficient moisture should be present at the time of manuring.
  • Fertigation may be done at monthly intervals with 75% of the recommended dose of the above fertilizers.
  • Phosphorous may be applied as super phosphate in the basins and incorporated or as DAP through drip when good quality of water is available.
For nut bearing coconut Palm, root feed TNAU coconut tonic @200ml/palm once in six months
  • At the time of planting, apply 50g of Azospirillum, 50 g of Phosphobacteria (or) 50 g of Azophos and 50 g of AM fungi.
  • Mix all the contents with sufficient quantity of FYM or any compost.
  • After planting apply the above biofertilizers once in 6 months/palm near to the
    feeding roots as that of fertilizer application
  • Any one of the green manure crops like sunnhemp, wild indigo, calapagonium or daincha may be sown and ploughed in situ at the time of flowering as a substitute of compost to be applied.
  • Sow sunnhemp @ 50 g/palm in the basin and incorporate before flowering.
  • Coir pith compost/vermicompost made from coir pith/ coconut leaves/ other wastes from coconut grove can be applied.
  • The interspace in the coconut garden has to be ploughed twice in a year in June-July and December – January.
  • Intercultural operation is essential to keep weed population under check, to enhance the utilization of the applied plant nutrients by the coconut trees, to facilitate proper aeration to the roots of coconut, to induce fresh root growth.

For the broad-leaved weeds, pre-emergence spraying of atrazine @1.0 kg a.i./ ha
for the control of grasses and sedges, post emergence spraying of glyphosate @ 10 ml and 20 g Ammonium sulphate / litre of water.

  • Inter/mixed crops may be selected based on the climatic requirement of the inter/mixed crop, irrigation facilities and soil type.
  • The canopy size, age and spacing of the coconut are also to be considered.
  • Market suitability should be taken into consideration before selecting an intercrop.

Below 7 years of age:

  • Any suitable annual crop for particular soil type and climatic condition may be raised as intercrops upto 5 years after planting depending upon the canopy coverage.
  • Groundnut, sesamum, sunflower, tapioca, turmeric and banana can be grown.
    Avoid crops like paddy and sugarcane etc.

7 – 20 years of age:

  • Green manure crops and fodder crops (Napier grass and guinea grass) alone can be grown.

Above 20 years of age

(20 years of age has to be adjusted based on the sunlight transmission of above 50% inside the canopy).
The following crops can be grown depending on the soil and climatic suitability.
(i) Annuals : Groundnut, bhendi, turmeric, tapioca, sweetpotato, sirukizhangu, elephant foot yam, ginger, pineapple
(ii) Biennials : Banana varieties, poovan and monthan are suitable.
(iii) Perennials : Cocoa, pepper (Panniyur 1 or Panniyur 2 or Panniyur 5 or Karimunda), nutmeg* and vanilla

  • Suitable areas are Pollachi tract of western region and Kanyakumari district.
  • For vanilla, use disease free planting material and maintain high vigilance to maintain a disease free crop.
  • Coconut + banana + sirukizhangu + bhendi is suitable system for the eastern region.
  • Crops like banana, pepper, cocoa, nutmeg, vanilla can be tried under multiple cropping system in suitable areas in the western region.
  • In all the systems, apply recommended quantity of water and manures and fertilizers to the intercrops separately
Root feeding of TNAU coconut tonic @ 200 ml / palm twice a year at six months interval decreases button shedding and increases the number and size of nuts.

1.Rhinoceros beetle: Oryctes rhinoceros

Population maximum during June – Sep coinciding with the onset of monsoon.

Symptoms of Damage:

  • The adult beetle bores into the unopened fronds and spathes.
  • Damage by the pest leads to 10 to 15% loss in yield.
  • Central spindle appears cut or toppled
  • Fully opened fronds showing characteristic diamond shaped cuttings
  • Holes with chewed fibre sticking out at the base of central spindle.

Management:

Mechanical Method:

  •  Adult beetle may be extracted from the palm crown using GI hooks.
  • Set up light traps following the first rains in summer and monsoon period to attract and kill the adult beetles.

Chemical Method:

  • The topmost three leaf axils around the spindle may be filled with any of the following mixtures as a prophylactic measure:

(a) Sevidol 8G 25 g + fine sand 200 g, which is to be done thrice in a year in April-May, September-October and December-January.

  • Place phorate 10 G 5 g in perforated sachets in two inner most leaf axils for 2 times at 6 months intervals.
  • Treat manure pits and other possible breeding sites with 0.01% carbaryl (50 % WP) on w/w basis. Treatment will have to be repeated every six months.

2.Red Palm Weevil: Rhynchophorus ferrugineus

Red palm weevil, a destructive pest of exotic plants, has been found in ...

Symptoms of Damage:

  • The hole can be seen on the stem with chewed up fibers protruding out.
  • Many times reddish brown liquid can be seen oozing out from the hole.
  • Inside portion of trunk is completely eaten and become full of rotting fibres.
  • In case of young palms the top withers while in older palms the top portion of trunk bends and ultimately breaks at the bend (wilting).

Management:

Cultural Method:

  • Remove and burn all wilting or damaged palms in coconut gardens to prevent further perpetuation of the pest.
  • Avoid the cutting of green leaves. If needed, they should be cut about 120 cm away from the stem in order to prevent successful inward movement of the grubs through the cut end.

Chemical Method:

  • In attacked palms, observe for the bore- holes and seal them except the top most one. Through the top most hole, pour 1% carbaryl (20gm/lt) or 0.2% trichlorphon @ one litre per palm using a funnel. 
  • In case of entry of weevil through the trunk, the hole in trunk may be plugged with cement / tar.
  • A slanting hole is made with the aid of an auger and the insecticide solution is poured with funnel.

3.Coconut Eriophyid: Aceria guerreronis

Eriophyid mites feeding injury to coconut (Cocos nucifera) - a photo on ...    Eriophyid Mites | USU

 Population maximum during June – Sep coinciding with the onset of monsoon.

Symptoms of Damage:

  • The earliest symptom on 2-3 month old buttons is pale yellow triangular patches seen below the perianth.
  • Oozing of the gummy exudation from the affected surface of the nuts.
  • Uneven growth results in distortion and stunting of nuts leading to reduction in copra yield.
  • The nuts are malformed with cracks and hardened husk.

Management:

Cultural Method:

  • Collect and destroy all the fallen buttons of the affected palm.
  • Grow intercrop (sun hemp, four crops/year) and shelter belt with casuarina 
  • Providing adequate irrigation.
  • Apply urea 1.3 kg, super phosphate 2.0kg and muriate of potash @ 3.5 kg/palm/year. 

Chemical Method:

Spot application of ecofriendly Botanicals

  • Round 1: Azadirachtin 1% (5 ml in one lit. of water)
  • Round 2: Neem oil + Teepol (30 ml in one lit. of water)
  • Neem cake application @ 5 kg per palm per year

4. Black Headed Caterpillar: Opisina arenosella

  • Severe damage to palms in coastal and back water areas and in certain internal packets of peninsular in India.
  • The pest occurs round the year with the spike in population during summer (Mar-May).

Symptoms of Damage:

  • The coconut trees of all ages are attacked.
  • Dried up patches on leaflets of the lower leaves, only three or four youngest leaves at the center of the grown remain green.
  • Galleries of silk and frass on under side of leaflets.

Management:

Cultural Method:

  • As a prophylactic measure, the first affected leaves may be cut and burnt during the beginning of the summer season.

Chemical Method:

  • When infestation is very severe in young palms and if the biocontrol is not likely to be effective, spray the undersurface of the fronds with dichlorvos 0.02% (Dichlorovos 100EC), malathion 50 EC 0.05% (1 ml/lt), quinalphos 0.05%, phosalone 0.05%.

5.Slug Caterpillar: Parasa lepida , Contheyla rotunda

Knowledge Based Information on Coconut :: Planting Seasons & Climate  Stinging Slug Caterpillars Archives - Page 5 of 22 - What's That Bug?

Symptoms of Damage:

  • The larvae is the destructive stage if the pest.
  • The young larvae feed on the lower epidermis of the leaf.
  • As they mature, the whole leaf blade is eaten leaving the midribs.
  • In heavy infestation, the larvae may defoliate the palm.

Management
Chemical Method:

  • Collect and destroy the immature stages of the insects by conducting study (or neem campaign) wherever possible and spray carbaryl 50 WP 2 gm/lit .
  • Spray carbaryl 50 WP 2 g/l.
  • Spray dichlorvos 76 WSC 2 ml / lit.

Mechanical Method:

  • Set up light traps to trap and collect adult moths. About 5 light traps may be installed per hectare

6.Coconut Skipper: Gangara thyrsis ; Suastus gremius

The Coconut Skipper butterfly | Hidari irava Prachantakham, … | Flickr

 Population maximum during June – Sep coinciding with the onset of monsoon.

Symptoms of Damage:

  • One half of the leaflets are cut and rolled into a case
  • The rolled leaflets are dried

Management:

Chemical Method:

  • Collect and destroy the immature stages of the insects by conducting study (or neem campaign) wherever possible and spray carbaryl 50 WP 2 gm/lit.
  • Spray dichlorvos 76 WSC 2 ml / lit.

7.Coreid Bug: Paradasynus rostratus

Coreid bug, Leptoscelis quadrisignatus, Coreidae | Andreas Kay | Flickr

Symptoms of Damage:

  • The adults and nymphs feed by de-sapping the contents on button and developing nuts below the perianth region.
  • Severe damage leads to nut fall and malformation of mature nuts.

Management:

Chemical Method:

  • Collect and destroy  the insects by conducting study (or neem campaign) wherever possible and spray carbaryl 50 WP 2 gm/lit.
  • Apply 0.1% carbaryl suspension on the newly opened inflorescence  excluding the leaves and older bunches (at 45 days interval).
  • Destruction of pollinating insects can be avoided if spraying is done in afternoon hours.
  • Spray dichlorvos 76 WSC 2 ml / lit.

Mechanical Method:

  • Set up light traps to trap and collect adult moths.

8.Bag Worm: Manatha albipes

Symptoms of Damage:

  • Small and irregular hole on the leaves.
  • Silken spin stick strand bags below the leaf.

Management:

Chemical Method:

  • Collect and destroy the immature stages and spray carbary 50 WP 2 gm/lit.
  • Spray dichlorvas 76 WSC 2 ml / lit.

Mechanical Method:

  • Set up light traps to trap and collect adult moths.

9.White Grub/ Cockchafer Beetle: Leucopholis coneophora

White coconut grub | These grubs live in the previously pict… | Flickr

Symptoms of Damage:

  • In nursery the grubs feet the tender roots and tunnel into the bole of the collar region resulting in drying and yellowing
  • White grubs are exposed when base of tree dug
  • Tuber crops grown as intercrops are also affected.

Management-

Chemical Method:

  • Soil application – Malathion 5 D 25 kg/ ha at the time of planting (Treat the soil with phorate 10G @ 100 g/palm or drench with chlorpyrifos 0.04% suspension. 

Physical Method:

  • Collect and destroy the adult beetles attracted to trees like neem, Ailanthus and Acasia on the receipt of monsoon showers (in the evening).

10.Termite : Odontotermes obesus

Symptoms of Damage:

  • Termites are likely to cause damage to transplanted seedlings particularly in the earlier stage. (wilting of seedlings)
  • Base of trunks plastered with runways made of soil and fiber

Management:

Cultural Method:

  • Locate termite mounds in or near the coconut nursery or garden and destroy.
  • Adoption of field sanitation by disposal of organic matter in nursery soil and covering germinating nuts with a layer of river sand.

Chemical Method:

  • Spray Copper Sulphate 1% or Cashew Nut Shell oil 80% or spray Chlorpyriphos @ 3ml/lit of water, Neem Oil 5% or NSKE 20% to preserve plaited coconut leaves from the termite attack.
  • Apply calcium at the base of the trunk for control of termite attack.
  • Swabbing with neem oil 5% once on the base and upto 2 m height of the trunk for effective control.

11.Lacewing Bug: Stephanitis typicus

Symptoms of Damage:

  • White spots on the upper surface of the leaves
  • Lace bug sucks sap from coconut foliage; it acts as a vector in transmission of Phytoplasma from root (wilt) affected palms to healthy palm.

Management:

Cultural Method:

  • Remove leaflets harboring these insects and destroy them.

Chemical Method:

  • Spray any one of the following;
    • Malathion 50 EC @ 2 ml/lt
    • Dimethoate 30 EC @1 ml/lt
    • Methyl demeton 25 EC @1 ml/lt
    • Phosphamidon 40 SL @1.25 ml/lt
    • Methomyl 25 EC @2 ml/lit
    • 3% Neem oil

12.Scale Insect : Aspidiotus destructor

Symptoms of Damage:

  • It occurs more in summer. Scale insects affects on leaves and nuts of coconut palms.
  • Scale forms a continuous crust over flower spikes, young nuts and lower surface of leaves.
  • Nymphs reside and develop in leaf by sucking the sap.

Management:

Chemical Method:

  • Spray Fish Oil Rosin Soap (FORS) 2.5% or spray Malathion. A second round is given after 20 days.

Biological Method:

  • Release of predatory Coccinellids, Chilocorus nigritius is found to be effective.

13.Mealy Bug: Pseudococcus longispinus

Symptoms of Damage:

  • Mealy bugs colonize on all tender plant parts like bases of spear leaf, spadix and inflorescence and beneath the perianth of the nut.
  • As a result, the leaves become highly stunted, suppressed, deformed and present a crinkled appearance.

Management:

Cultural Method:

  • Remove leaflets harbouring these insects and destroy them.

Chemical Method:

  • Spray any one of the following;
    • Malathion 50 EC @ 2 ml/lt
    • Dimethoate 30 EC @1 ml/lt
    • Methyl demeton 25 EC @1 ml/lt
    • Phosphamidon 40 SL @1.25 ml/lt
    • Methomyl 25 EC @2 ml/lit
    • 3% Neem oil

1. Nitrogen (N) Deficiency

Symptoms

  • N deficiency is typically caused by insufficient N in the soil.
  • Yellowing starts from tip to base of the lower leaves and will proceed up.
  • As the deficiency progresses, younger leaves will also become discoloured.
  • Older leaves are golden yellow colour.

Management

Foliar application of 2% urea thrice at fortnightly interval or soil application of 1-2 kg urea / tree or root feeding of 1% urea (1 g/litre of water) 200 ml twice a year.

2. Potassium (K) Deficiency

Symptoms

  • Symptoms first appear on oldest leaves and later spread to young leaves.
  • Translucent yellow or orange spots develop on leaflets (Yellowing of leaf margin).
  • Older leaves are showing necrotic spotting as well curling of leaflet tips.
  • Leaflets with necrotic areas along the margins which later wither
  • The tree appears yellow and nicky, the trunk in slender with few short leaves

Management

  • Application of resin coated K2SO4 @ 3 – 4 kg/tree, four times a year along with 2 kg MgSO4 / tree.
  • Root feeding of 200ml of 1% KCL per tree thrice a year.

3. Phosphorus Deficiency

Symptoms

  • Purple coloration in leaves (In severe cases may leaves turn yellow before drying prematurely)
  • Sluggish growth
  • Leaves stay upright
  • Premature leaf shedding

Management
Foliar spray of DAP 2% twice at fortnightly interval or soil application of FYM 5kg/tree. Root feeding of 1% DAP 2 ml twice a year.

4. Sulphur Deficiency

Symptoms

  • Typical symptoms are yellowish-green or yellowish-orange leaflets.
  • Old leaves remain green.
  • Leaves droop as the stem becomes weak.
  • Nuts may fall prematurely.
  • Copra is rubbery and of poor market quality.

Management

  • Soil application of gypsum 2 – 5 kg/tree/year.
  • Root feeding of 0.2% (2g/litre of water) gypsum.

5.Boron (B) Deficiency

Symptoms

  • Failure of newly emerging spear leaves to open normally.
  • Multiple unopened spear leaves may be visible at the apex of the canopy.
  • Boron deficiency also occurs in inflorescence and nuts.
  • The inflorescence and nuts are become necrotic.

Management

  • Foliar spray of 0.2 % (2g in 1 lire of water) borax at the rate of 75 – 100 ml per seedling.
  • Spraying is commonly practiced when coconut palms are at the nursery stage.
  • 1 year old – Borax 5-10 g/plant per year 2-3 years old – Borax 15- 20 g/plant per year 4 years old and more – Borax 30 -50 g/plant per 2 years

6.Manganese (Mn) Deficiency

Symptoms

  • Manganese deficiency is very common on alkaline soils.
  • The newest leaves palms emerge chlorotic with longitudinal necrotic streaks.
  • Newly emerging leaflets appear necrotic and withered on all but basal portions of the leaflets.

Management

Soil application of MnSO4 @ 25kg/ha

7.Magnesium (Mg) Deficiency

Symptoms

  • In severe cases leaflet tips may become necrotic.
  • Older leaves become bronzed and dry appearance.
  • Leaflets show necrosis and turn to reddish brown with translucent spots yellowing starts at the tip and spreads to the base

Management

  • Soil application of MgSO4 1-2 kg/tree/year.
  • Root feeding of 200 ml of 0.2% MgSO4 twice a year.

8.Zinc (Zn) Deficiency

Symptoms

  • Formation of small leaves wherein the leaf size is reduced to 50%.
  • Leaflets become chlorotic, narrow and reduced in length.
  • In acute deficiency, flowering is delayed.
  • Zinc deficiency will also lead to button shedding.

Management

Soil application of ZnSO4 @ 25kg/ha

9 Iron (Fe) Deficiency

Symptoms

  •  Appears on palms growing in poorly aerated soils or those that have been planted too deeply.
  • Water logged soils and deep planting effectively suffocate the roots and reduce their effectiveness in taking up nutrients such as Fe.
  • Chlorosis or yellowing between the veins of new leaves 

Management

Application of Feso4 0.25 to 0.5 kg/tree/year

10.Calcium (Ca) Deficiency

Symptoms

  • Young leaves exhibit narrow white bands at margins
  • Interveinal (chlorosis)
  • Rusty appearance in leaf margin
  • Rolling up of leaves
  • Occurs only in acid soil

Management

Soil application of lime based on lime requirement and root feeding of 1% calcium nitrate

11.Copper (Cu) Deficiency

Symptoms

  • Coppery bluish leaf
  • Rolling of terminal leaves due to loss of turgor
  • Leaves appear to be bleached grey
  • Fail to produce flowers

Management

Soil application of CuSO4 @ 25 kg per ha.

12.Molybdenum (Mo) Deficiency

Symptoms

  • Chlorotic leaf blade
  • Small slender leaves
  • Rosetted plants
  • Occurrence of whip tail

Management

Root feeding of 0.05% (0.5g/litre of water) Sodium Molybdate

Micronutrients                                  (Soil application / tree / year)
Borax                                                                     50 g
Gypsum                                                                 1.0 kg

Magnessium sulphate                                            500g
Grow sunnhemp as intercrop twice a year (Seed rate 30 kg/ha)

Method of application

  • The botanicals should be applied in the sequence indicated above at 45 days interval using a one litre hand sprayer.
  • Rocker or Pedal sprayer can be used for spraying small trees.
  • The spray should be applied at the crown region by a climber covering only the top six bunches during non rainy season
  • The bunches must be covered well by the spray fluid and approximately one litre of spray fluid may be required per tree
  •  
  • Precautions and safety measures
  • Spraying should be avoided during windy season to prevent contamination
  • At the time of spraying, protective mask and clothing should be used
  • Wash face and hands cleanly with soap after spraying.

 

1.TANJORE WILT : Ganoderma lucidem and Ganoderma applanatum

Coconut Tanjore wilt Disease management - YouTube

Symptom:

  • Yellowing and drooping of the outer whorl of leaves.
  • Decaying of tissues at bleeding point and rotting of the basal portion of the stem
  • Bracket formation at the base of the trunk during rainy season.
  • Ultimately the palm dies off.

Chemical method

  • The bleeding patches in the stem may be chiseled and protected with tridemorph (5% calxin) and subsequently with hot coal tar.
  • Root feeding with Tridemorph 2ml or Hexaconazole 1 ml with 100 ml of water (3 times at 3 months interval).
  • Forty litres of 1% Bordeaux mixture should be applied as soil drench around the trunk in a radius of 1.5m

2.BUD ROT: Phytophthora palmivora

Coconut Cultivation In India | Coconut Farming | नारियल की उन्नत खेती

Symptom:

  • Normally young palms are more susceptible, particularly during monsoon.
  • In seedlings, yellowing of one or two younger leaves.
  • Basal tissues of the leaf rots quickly and can be easily pulled out from the crown.
  • In the later stages the spindle withers and drops down.

Chemical method

  • Remove all the affected tissue of the crown region and drenching crown with Copper oxychloride 0.25%.
  • Apply Bordeaux paste .
  • Spray 0.25% Copper oxychloride or 1 % Bordeaux mixture on the crown.
  • Leaf axil filling with Sevidol 8G, 25 g mixed with 200 g sand is recommended to manage red palm weevil infestation of affected palms.
  • Spray with Copper oxychloride 0.25% after the onset of Monsoon.

3.LEAF BLIGHT (LB):  Lasiodiplodia theobromae

Coconut (Cocos nucifera): Bipolaris leaf spot and blight | Flickr

Symptom:

  • Leaf blight causes serious damage in seedlings, leaves and nuts of adult palms.
  • Generally the adult leaves in the outer whorls are affected.
  • Dark grey to brown lesions with wavy to undulated margins appear from the apex of the nuts.
  • Maximum incidence was observed during summer months.

Chemical method

  • Spray 1.0 per cent Bordeaux mixture or 0.25 percent Copper oxychloride (2 times at 45 days interval during summer months).
  • Root feeding of Carbendazim 2 g or Hexaconazole/ Tridemorph 2 ml + 100 ml water (3 times at 3 months interval).

4.STEM BLEEDING DISEASE: Thielaviopsis paradoxa

STEM BLEEDING, COCONUT PALM - INDIA: (KARNATAKA)

Symptom:

  • Disease is faster during July to November.
  • The lesions spread upwards as the disease progresses.
  • The liquid oozing out dries up and turns black.
  • The tissues below the lesions become rotten and turn yellow first and later black

Chemical Method:

  • Chisel out completely the affected tissues and paint the wound with tridemorph 5% or Bordeaux paste.
  • Apply coal tar after 1-2 days on the treated portion. Burn off chiseled pieces.
  • Root feed with Tridemorph 5ml in 100 ml water, thrice a year during April-May, September-October and January-February to prevent further spread of lesions.

5.ROOT WILT (OR) KERALA WILT DISEASE: Phytoplasma

Symptom:

  • Tapering of terminal portion of the trunk.
  • Reduction of leaf size
  • Abnormal bending or Ribbing of leaf lets termed as flaccidity.
  • Flowering is delayed and also yield is considerably reduced.
  • The characteristic symptom is the flaccidity of leaflets. 

Chemical Method

  • Magnesium may be supplied @ 500 g MgO per palm per year
  • Treat the top tow leaf axils with insecticide preparation  by mixing phorate 10 G with 200 g sand or powdered neem cake 250 g.
  • Mix equal quantity of sand place around the base of the spindle.

6.LEAF ROT DISEASE: Colletotrichum gloeosporioides

Types of coconut tree diseases: (a) Leaf rot, (b) Leaf spot | Download ...

Symptom:

  • Gradually these spots enlarge and coalesce resulting in extensive rotting.
  • As the leaf unfurls the rotten portions of the lamina dry and get blown off in wind, giving a “fan” shape to the leaves.

Chemical method

  • Pour fungicide solution of Hexaconazole – 2ml or Mancozeb – 3g in 300ml water per palm to the base of spindle leaf. 2-3 rounds of spraying are sufficient in case of mild infection.
  • Spray the crowns and leaves with 1% Bordeaux mixture or While spraying, care has to be taken to spray the spindle leaf.

Rejuvenation of existing garden

  • The low yield in vast majority of gardens is due to thick population, lack of manuring and irrigation.
  • These gardens could be improved if the following measures are taken.
    i. Thinning of thickly populated gardens
  • In the farmer‘s holdings where thick planting is adopted, many trees give an yield of less than 20 nuts/palm/year.
  • By cutting and removal of these trees, the yield could be increased. Besides, there is saving in the cost of cultivation and increase in net profit.
  • After removal of low yielding trees, the populations should be maintained at 175 palms/ha.
    ii. Ensuring adequate manuring and irrigation:
    The yield can be increased in the existing gardens when manuring + irrigation + cultural practice is adopted as per recommendation.
  • Pencil point disorder (Micronutrient deficiency)
    Because of micronutrient deficiency, the stem will taper towards its tip with lesser number of leaves.
  • The leaf size will be greatly reduced and the leaves will be pale and yellow in colour.
  • Along with the recommended fertilizer dose, 225 g each of Borax, Zinc sulphate, Manganese sulphate, Ferrous sulphate, Copper sulphate and 10 g of Ammonium molybdate may be dissolved in 10 litres of water and poured in the basin of 1.8 m radius.
    This disorder can be corrected if noticed early.
  • Severely affected palms may be removed and replanted with new seedlings.
  • Button shedding
    Shedding of buttons and premature nuts may be due to any one of the following reasons:
    i) Excess acidity or alkalinity
    ii) Lack of drainage
    iii) Severe drought
    iv) Genetic causes
    v) Lack of nutrients
    vi) Lack of pollination
    vii) Hormone deficiency
    viii) Pests
    ix) Diseases
    The following remedial measures are suggested.
  • Rectification of soil pH
  • Excess acidity or alkalinity of soil may cause button shedding.
  • If the soil pH is less than 5.5, it is an indication of excess acidity.
  • This could be rectified by adding lime.
  • Increase in alkalinity is indicated by soil pH higher than 8.0.
  • This situation could be rectified by adding gypsum.
    Providing adequate drainage facilities
  • Lack of drainage results in the roots of coconut trees getting suffocated for want of aeration.
  • Shedding of buttons occur under such condition.
  • Drainage channels have to be dug along the contours to drain the excess water during rainy season.
    Management of young coconut gardens under waterlogged conditions
    (i) A trench between two rows of young coconut palms should be dug during onset of the monsoon rains.
  • The size of the trench is 3 m width, 30 – 45 cm depth to entire length of field.
  • The soil excavated from the trench should be placed along the rows of palms to make a raised bed.
    (ii) Form mound around the young palms to a radius of 1.2 m width with height of 30 –45 cm.
    Genetic causes
  • In some trees button shedding may persist even after ensuring adequate manuring, irrigation and crop pest and disease management.
  • This is an indication of inherent defect of the mother palm from which the seed material was obtained.
  • This underlines the need for proper choice of superior mother palm for harvesting seed coconut to ensure uniformly good yielding trees.
    Lack of nutrition
  • Button shedding occurs due to inadequate or lack of manuring.
  • The recommended dose of manurial schedules and proper time of application are important to minimise the button shedding.
  • Apply extra 2 kg of muriate of potash with 200 g of Borax/palm over and above the usual dosage of fertilizer to correct the barren nuts in coconut for period of 3
    years.

Boron deficiency or crown choke disorder
Apply 200 g of borax/palm/year in two splits.

Lack of pollination

  • Button shedding also occurs due to lack of pollination.
  • Setting up of beehives @ 15 units/ha may increase the cross pollination in the garden.
  • Further the additional income obtained through honey, increases the net profit per unit area.
    Hormone deficiency
  • The fertilized female flowers i.e., buttons shed in some cases.
  • By spraying 2, 4- D at 30 ppm or NAA 20 ppm (30 mg per litre of water) on the inflorescence one month after opening of the spathe, the setting percentage could be increased.
    Pests
  • Button shedding may happen due to the attack of bug.
  • Spraying of systemic insecticides like Methyl dematon 0.025% (1ml/lit) or Dimethoate 0.03% (1ml/lit) may reduce the occurrence.
    Diseases
  • Button shedding also occurs due to disease incidence such as basal stem rot.
  • Adoption of control measures suggested for the disease reduces not only spread of the disease but also prevents shedding of buttons.
  • The need for collecting seed materials from high yielding coconut palms is highly essential in a perennial crop like coconut.
    The following points may be remembered.
    Mother palm selection
  • Select seed gardens, which contain large proportion of high yielding trees with uniformity in yielding ability.
  • Trees growing closer to households, cattle shed, compost pits and other favorable conditions should be avoided.
  •  High yielding mother palms giving not less than 100nuts/palm/annum should be chosen for collecting seednuts.
  • Alternate bearers should be avoided.
  • The age of the palm chosen be middle age i.e., from 25 to 40 years.
  • Even trees with 15 years age can be selected, if it is high yielding and has stabilized yield.
  •  The mother palm should have straight trunk, spherical or semi spherical crown, high rate of leaf and spathe production, short and stout petiole, more number of female flowers regular bearing habit, non – buckling bunches, high setting parentage, medium in nut size, high copra outturn and free from pest and diseases.
  • A good regular bearing mother palm produces on an average one leaf and an inflorescence in its axil every month.
  • So, there will be twelve bunches of varying stages of maturity at any one time.
  • Avoid trees producing habitually barren nuts.
  • Harvest seednuts during the months of February – August to get maximum germination and good quality seedlings.
  • Harvest the bunches intended for seednut by lowering them to the ground using a rope to avoid injury to seednuts
  • The seednuts should be round in shape and when tapped by finger should produce metallic sound.
  • Fully ripe nuts develop twelve months after fertilisation.
  •  To get more quality seedlings, the seednuts of tall and hybrid are to be air cured for one month followed by sand curing for two months.
  • For dwarf varieties, the air curing should be lesser than one month followed by sand curing for two months.

1.Select nursery area in a well drained plot with coarse texture soil near water source for irrigation. Nursery can be raised in the open space with artificial shade or in the adult coconut garden.
2.Plant seednuts in long and narrow beds at a spacing of 30 x 30 cm either horizontally or vertically in deep trenches with 20-25 cm depth. Five rows of nuts may be planted in each bed accommodating 50 nuts per row.
3.Irrigate the nursery beds once in three days.
4.Keep the nursery free of weeds. To manage the weed problem in coconut nursery, growing sunnhemp 2 times (each harvested at flowering stage) followed by one hand weeding at 6th month was found to be very effective besides yielding green manure for
manuring the adult coconut palms.
5.Provide shade to the nursery by raising Sesbania or Leucaena on the sides of beds.
6.The seednuts start germination 6 – 8 weeks after planting and germination continues upto six months. Select seedlings that germinate before 5 months after planting. Remove those nuts which do not germinate 5 months after sowing.
7.Regularly survey for pest and diseases
8.Select seedlings 9 to 12 months after planting. Seedlings, which have germinated earlier, having good girth at collar and early splitting of leaflets, should be selected for planting. Do not select the so called Kakkamukku Pillai i.e., seednuts which have just germinated.
Eliminate the seedlings which are deformed or having stunted growth.
9.Remove the seedlings from the nursery by lifting with spade. Do not pull out the seedlings by pulling leaves or stem.
10. Select quality seedlings with a minimum of 6 leaves and girth of 10 cm at collar.

Harvesting

  • Twelve months old nuts are harvested at the interval of 30-45 days for seed as well as copra making and culinary purposes.
  • For household use keep the nuts in vertical direction. However, for tender nut purposes 7 to 8 months old nuts are harvested. The nuts can be harvested using coconut climbers.
  • Nuts which are 11 months old give fiber of good quality. This is suitable for coir fiber.
  • In case of tall the nuts harvested for seed purpose can be stored for 2 to 3 months period before sowing, whereas in case of dwarfs and hybrids, nuts should be sown with in a period of 10 –15 days of harvest.
  • On an average, we can have eight harvests, though the coconut palm produces inflorescence every month.