Milestone achievements

1. Crop Improvement

High yielding Coconut hybrids / varieties released

Three T x D hybrids, one T x T hybrid and two tall coconut varieties were released so far commercial cultivation in Tamil Nadu.


VHC 1 : A cross between East Coast Tall x Green Dwarf, released in 1982, which comes to flowering in 3 ½ years with a average nut yield of 120 nuts / palm / year which is 38 percent higher over ECT coconut
VHC 2 : A cross between East Coast Tall x Malayan Yellow Dwarf, released in 1988, with a average nut yield of  142 nuts / palm / year (55 % higher over ECT)
VHC 3 : A cross between East Coast Tall x Malayan Orange Dwarf, released in 2000, with a average nut yield of  157 nuts / palm / year and 67 % higher over ECT coconut
VPM 5 : A cross between Laccadive Ordinary Tall x Cochin China Tall, released in 2015, which comes to flowering in 3 ¾ years with a average nut yield of  161 nuts / palm / year
VPM 3 : A Tall coconut variety selected from Andaman Ordinary released in 1994, which comes to flowering in 5 ½ years, with a average nut yield of  92 nuts/palm/year
VPM 4 : A selection from West Coast Tall (WCT), which was released in 2007 which comes to flowering in 5 years, with a average nut yield of  159 nuts/palm/year

a. State level (TNAU ) b. National level (AICRP(P )

VHC 1 (1982)

East Coast Tall x  Green Dwarf



VHC 2 (1988)

East Coast Tall x Malaysian Yellow Dwarf

VPM 3 (1994)

Selection from Andaman Ordinary Tall


VPM 4 (2011)

Selection from West Coast Tall



VHC 3 (2000)

East Coast Tall x Malaysian Orange Dwarf

VPM 5 (2015)

Laccadive Ordinary Tall  x Cochin China


A. Agronomy

2. Crop Management

  • In coconut nursery, weeds can be effectively checked by growing sunnhemp twice immediately after sowing the seed nuts and trampled in situ at flowering followed by one hand weeding at 6th
  • A spacing of 7.5 x 7.5 m is optimum for higher nut yield per unit area.
  • A multispecies cropping system model consisting of coconut + black pepper + banana + Elephant Foot Yam+ coriander recorded the maximum net return of Rs. 57577 with the B: C ratio of 2.16 followed by Coconut + Banana + black pepper recorded the net return of Rs. 45,557 with the B: C ratio of 2.08.
  • The herbal plants viz. Sitharathai, Aloe vera, Tulsi, lemon grass and patchouli were found to be best suited intercrop in adult coconut garden.
  • Banana is the most profitable intercrop in coconut (B: C ratio 1:4.2) when intercropped at 2.5 x 2.5 x 5.0 m spacing (four banana in between four coconut palms).
  • Turmeric, pineapple, tapioca, elephant foot yam, cocoa, bhendi and curry leaf are also best suited intercrops in coconut.
    • For basin irrigation, 410 litres of water / palm once in 5 – 7 days during March – September and once in 8 – 10 days during October to February is optimum for eastern region of Tamil Nadu depending upon the soil type.
    • In drip irrigation, 80 litres / day / palm during March – September and 50 litres / day / palm during October – February is sufficient for eastern region of Tamil Nadu.
    • In the basin of 1.8 m radius from the base of the palm, husk of 150 nuts in convex position or 15 numbers of dried coconut fronds or 10 cm height (30 kg) of coconut coir pith is ideal moisture conservation practice for coconut.
    • Sowing of sunnhemp @ 50 g / palm or 25 kg / ha twice a year and in situ incorporation is effective for enhancing soil organic matter status of the soil.


  1. Soil Science and Agricultural Chemistry


  • 56: 0.32:1.20kg NPK / palm / year with 50 kg FYM in two equal splits for higher nut yield in tall coconuts.


  • 0:0.25:2.0 kg NPK / palm / year with 60 kg FYM in two equal splits for higher nut yield in hybrid coconuts.
  • For the 2nd, 3rd and 4th year – ¼ th, ½ rd and ¾ th of the above recommended dose of fertilizers  is to be applied and from the 5th year onwards full dose is to be applied.


  • Out of recommended NPK (560:320:1200 g NPK / palm / year), 50% N as CCP and 50% NPK as fertilizer found to be effective in sustaining the nut yield of coconut, soil fertility in the long run and also higher economic return.


  • For hybrid coconut, out of recommended fertilizer level of 1000:250:2000 g NPK / palm / year along with 60 kg of organic manures, 50% of recommended nitrogen may be applied as organic manure of either vermicompost or composted coir pith and the remaining 50% nitrogen may be applied as fertilizer. The organic manure that carries 50% nitrogen can satisfy the organic matter requirement of organically poor coconut soils


  • Application of organic Cocomix (40 kg Composted Coir Pith (CCP) / Vermicompost (VC) + 500 g Rock) Phosphate (RP) + 12.50 g of each Azospirillum (AZOS) and Phosphobacteria (PB) + 250 groundnut (GN) cake) once in a month in twelve equal splits for the first year and subsequently once in three months , in four equal splits for tall coconut and double the quantity as per the above schedule for hybrid coconut is adequate for optimum nut yield and better soil health


  • Application of new formulation of major nutrient mixture for tall (2:1:4 NPK @ 2.5 kg / palm / 6 months) and hybrid (4:1:8 NPK @ 4.0 kg /palm / 6 months) coconut for enhanced nut yield and soil nutrient availability


  • TNAU formulation of refined micronutrient mixture to tall and hybrid coconut @ 1 kg/palm/year for enhancing nut yield, micronutrients availability in soil and to keep their optimum level in index leaf tissue.


  • Soil application of recommended NPK (560:320:1200 g NPK / palm / year), FYM (50 kg) in two equal splits along with TNAU-coconut tonic @ 200 ml / palm / 6 months for higher nut yield and economic return on ECT coconut.



  1. Crop Physiology
  2. Management strategies for button shedding and barren nut production
  • 20 ppm  Planofix spray at 30 days after opening of spathe, application of 1 kg potash and 200 g borax in addition to recommended fertilizers.
  • Root feeding with TNAU coconut tonic @ 200ml / palm once in six months
  1. Management of pencil point disorder
  • Root feeding of ferrous sulphate @ 2000 ppm (0.4 g / 200 ml) per palm at quarterly interval
  • Application of each 250 g of zinc sulphate, Borax, Manganese sulphate, Copper sulphate and 10 g Sodium molybdate per palm continuously for three years

3. Crop Protection

A. Agricultural Entomology

a. Rhinoceros beetle

  • Placement of three naphthalene balls at the base of three inner most fronds repel the adult beetles.
  • Crown application of neem seed powder + sand (1:2) @ 150 g / palm (or) neem seed kernel powder + sand (1:2) @ 150 g / palm applied to the base of 3 inner most leaves.
  • Leaf axil application of Phorate granules @ 5 g + 100 g sand (or) carbofuran 3 G @ 10 g + 100 g sand
  • Use of pheromone trap (Rhinolure) @ 1 / ha with different natural products such as coconut toddy, tender coconut water and palmyrah fruit juice to attract adults.

b. Red palm weevil

  • Root feeding of Monocrotophos 10 ml + 10 ml of water effectively controls the red palm weevil.
  • Use of pheromone trap (Ferrolure) @ 1 / ha in the management of red palm weevil using different natural products such as coconut toddy, tender coconut water and palmyrah fruit juice.

c. Eriophyid mite


  • Spraying of Triazophos @ 5 ml / litre of water or Carbosulfan @ 2 ml / litre of water  per palm reduced the mite population up to 70 per cent.
  • Spraying of  the following botanical pesticides alternatively for 45 days intervals are effective

1% Azadirachtin  @ 5 ml / litre / palm

3% Neem oil @ 30 ml / litre / palm

1% Azadirachtin  @ 5 ml / litre / palm

  • Root feeding of 1% Azadirachtin @ 10 ml + 10 ml of water / palm thrice a year is recommended.
  1. Plant Pathology

a. Basal stem rot

  • Root feeding of 1.3g Aureofungin-sol + 0.5 g Copper sulphate or 2 ml of Tridemorph in 100 ml of water combined with soil drenching of 40 litres of 1% Bordeaux mixture thrice at quarterly interval effectively controls the disease.
  • Application of 5 kg neem cake / palm / year reduces BSR, banana intercropping in BSR affected gardens contains the disease
  1. Leaf spot
  • Root feeding 2.0 g Thiophanate-methyl or Carbendazim in 100 ml of water reduces the disease incidence.
  1. Leaf blight
  • Root feeding of 2 ml of Tridemorph or 4g of Carbendazim in 100 ml of water
  1. Bud rot
  • Apply 1% Bordeaux mixture or 0.3% Copper oxychloride twice in 15 days interval.
  • Drenching of 1% Bordeaux mixture to the surrounding palms

Annual Report (2018-19)

Crop Improvement:

  • Fourteen different cross combinations are being evaluated for quality tender coconut. Higher volume of tender nut water was recorded in Chowghat Orange Dwarf x Cochin China (490 ml/nut). High TSS and reducing Sugars were observed in Chowghat Orange Dwarf x Kappadam Tall (6.2 degree brix & 3.7 g/100 ml tender nut water)
  • Among the Tall x Dwarf and its reciprocals, West Coast Tall x Malayan Orange Dwarf recorded highest whole nut weight of 1193 g with higher kernel weight with 360 g, while the Malayan Orange Dwarf x West Coast Tall recorded the highest annual nut yield of 93 nuts /palm. Among the hybrids evaluated for tender coconut water quality, Malayan Orange Dwarf x West Coast Tall was found to be superior with 5.800 brix and with good organoleptic score.



Crop Production

  • Four levels of organic and inorganic nutrient combinations are being evaluated under coconut based cropping system. 50% of recommended NPK + 50 % of organic recycling with vermicompost + vermiwash application + biofertilizer application and in situ green manuring recorded higher net income of Rs.5,54,125/ha when compared to recommended NPK application in coconut as pure crop (Rs. 224700/ ha)
  • Six cocoa verities / hybrids viz., T1 : VTLCC 1, T2 : VTLCH 1, T3: VTLCH 2, T4 : VTLCH 3, T5 : VTLCH4 ,  T6 : VTLC 1 (control) were planted and the performance as intercrop in coconut gardens is being evaluated. Among the cocoa clones and hybrids, VTLCH 1 has performed well in terms of  stem girth (37.32 cm ), yield attributes  , pod weight (145.60 g/pod), number of beans (29.00 per pod) and dry beans yield (2.30 kg/tree) followed by VTLCH 2 and VTLCC 1.

Crop protection

Agricultural Entomology

  • Among six cross combinations of Tall x Tall and Dwarf x Dwarf, Benaulim Green Round Tall x Andaman Ordinary Tall, Chowghat Orange Dwarf x Malayan Yellow Dwarf are found to be resistant to rhinoceros beetle with lesser leaf damage of 10.4 and 15.0 per cent respectively. Among five cross combinations of Dwarf x Dwarf, Chowghat Green Dwarf x Malayan Green Dwarf, Malayan Yellow Dwarf x Chowghat Green Dwarf were found resistant to red palm weevil which recorded nil damage.

Plant Pathology

  • Root feeding of Hexaconazole @ 3 ml + 100 ml water at quarterly interval was most effective in containing the basal stem rot disease by registering only 0.48 per cent increase in disease incidence as against 3.51 per cent in control followed by the root feeding of Zineb 68% + Hexaconazole 4%WP @ 4g + 100 ml water at quarterly interval by registering 0.84 per cent increase in disease incidence.