HORT 282 :: Lecture 19 :: COFFEE

COFFEE
(Coffea arabica and C.canephora, Rubiaceae)

  Coffee, native of Ethiopia, was introduced into India sometime during 1600 AD by a Muslim pilgrim, Baba Budan on the hills near Chikmangalur. Coffee seedlings  were  then  planted  in  the  backyards  and  it  was  not  until  the  late  1820 s  that  commercial  plantations  were  started  in South  India  by  British  entrepreneurs. Now  coffee  cultivation  is  mainly  confined  to  the  States  of  Karnataka, Kerala, Tamilnadu  ND  Andhra Pradesh  and  on  a  limited  scale  to  Arunachala  Pradesh, Assam, Madhya Pradesh,  Manipur, Meghalayaa, Mizoram, Nagaland,  Orissa, Sikkim, Tirupura  and  West  Bengal. The  present  area  under  coffee  is  2,43,117 hectares  of  which arabica  accounts  for 49.41 % and  robusta 50.59 % with  a  total  production  of  about 1,75,000  tonnes  . About   60 % is exported annually earning around Rs. 300 crores and rest consumed internally. There are  99,000 registered growers  of  whom  97.13% are  small  growers  with  10  hectares   and  below. This plantation employs about 3, 71,655 workers.
Botany:
Though  the genus  coffea  consists  of  about 70  species,  only  3  species  are  of  economic  importance. They are 1) C. arabica (Arabica coffee), 2) C. canephora (Robusta coffee) and 3) C. liberica (Tree coffee).  The first two species are extensively cultivated. The important differences among these two species are:

CHARACTER	C. arabica	C. canephora
1.  Ploidy	Tetraploid (2n=44)	Diploid (2n=22)
2. Adaptability	Higher  elevation	lower  elevation
3. Plant  status	A small tree, a shrub or a bush under training.	A    bigger tree than arabica.
4. Leaves	Dark green	Pale  green
5. Blossoming	Bloom in 9-10 days after the receipt     of blossom showers.	Bloom in 7 days after the receipt     of blossom showers.
6. Flowers	Scaly, small bracts, per axil 4-5 inflorescence of 1-4 flowers per inflorescence.	Leafy and expanded bracts with 5 to 6 flowers per inflorescence.
7. Berries	10-20 per node oblong to round in shape.	40-60 or more per node, small.
8. Fruit development	8-9 months	10-11months
9. Root  system	Small but deep.	Large but  shallow
10. Pollination & fertilization	Self pollinated & Self fertile.	Cross  pollinated  & Self –sterile.

 

 

 

 

    

 

 

  The  coffee  plant  has  a  prominent  vertical  stem  with   horizontal  primary  branches  arising  from  it  in  pairs  opposite  to  each  other. Another  upright  shoot,  sucker,  arises  from  the  main  stem  especially  in  a  matured coffee  plant  in  between  the  primary  lateral  branch  and  the  leaf  or  its  suar. It grows vertically like the main stem. These  primary  branches  give  rise  to  laterals  which  in  turn  produce  tertiary  and  quartenary  branches. The secondary  and  tertiary  types  arise  towards  the  distal  end  of  the  branch  just  above the  axil  and  the  other  type  known  as  axillary  bud  which  grows  in  the  leaf  axil  and  is capable  of  growing  into  a  flower  cluster  or  a  lateral  shoot. The axillary bud provides the main cropping wood for the plant.
Coffee  is  a  short  day  plant  and is  South India,  flower  initiation  takes place  between  September  to  March. The  flower buds  grow  into  a  definite  size  under  fairly  cold  winter  conditions  and  undergo  a  period  of  dormancy  due  to  the  onset  of  drought coupled  with  high temperature, long day  and high light  intensity  conditions  prevailing  in  dry  months (November to march) depending upon the places. There is practically no vegetative growth   during these dry months. Immediately  after  the  blossom  showers, growth  changes  are  conspicuous  in  flower buds  on  the  third  day  following  rains  due  to  the  moistening  of  the  flower buds, soil  wetness  and  low  temperature  that  follows  immediately  after  rain. This causes the plants to blossom within 7 to 10 days.  This  imposed  dormancy  is  a  necessary  event,  as  it  enable  single  harvest  ,  otherwise,  coffee  will  be  blooming  through out  the  year  resulting  in  staggered  harvesting  concomitant  with  increased  cost  of  picking , etc. The fruit is a drupe and normally contains two seeds. Abortion  of  one    ovule  due  to  non- fertilization  leads  to  the  formation  of  a  single  seeded  fruit, called  pea  berry .  Sometimes  , 3  or  more  seeds  may  be  present  due  to  trilocular  ovaries  or  false  polyembryony  and is  often  called  triangular  seeds. Occasionally,  formation of  more  than  one  ovule  per  locule  is  seen  and  such  seeds  are  known  as  elephant  bean.
Climate and Soil
Climatological  factors  like  rainfall,  temperature,  elevation  and  aspect  can  influence  economic  production  of  coffee  much  more  than  soil  factors. Soil  should  be  deep,  well  drained,  slightly  acidic  in reaction  and  rich  in  organic  matter  content.
The  optimum  soil  and   climate  requirements  for  arabica  and  robusta  under  south  Indian  conditions  are  as  follows.

Varieties

Nursery
Healthy  and  mature  fruits  of  normal  sizes  and  appearance,  three  squatters  to  fully  ripe  are  harvested  from  specially  selected  and  marked  coffee  plants for   uses  as  seed  bearers.  Floats  are  discarded,  the  sound  fruits  are  pulped, the beans  drained  and  sieved  to  remove  defective  beans.  The  beans  are  then  mixed  with  sieved  wood – ash , evenly  spread  out  to  a  thickness  of  about  5 cm  and  allowed  to  dry  to  facilitate  uniform  drying. Excess ash is rubbed - off after five days of drying.
Germination beds raised  to  a  height  of  about  15  cm,  one  metre  width and  of  convenient  length are  prepared, Four baskets  of  fully  mature  cattle  manure or  compost, about 2 kg of finely sieved agricultural lime and 400 g of rock phosphate  are  incorporated in a  bed  measuring 1mX 6m.
Seeds  should  be  sown with  the  flat  side facing  the  soil  at  a  distance  of  1.5 to 2.5 cm  from  one  another  in  regular rows. A thin layer of fine soil is then spread. The bed is covered with a layer of about 5 cm of paddy straw. The beds  are  watered  daily  and  protected from direct  sunlight  by  and   overhead pandal  constructed for this  purpose. The seeds germinate in about 45 days. The seedlings are then transplanted to secondary nursery beds or raising polybag plants.

 

       Coffee  seedlings  are  transplanted  to  polythene bags  of 23 cm X 5 cm  with 150   gauge  thick  in  February or March  when  they  are  at  the  bottom  or  topee  stage. The  bags  are  filled with  a  prepared  mixture  of  6  parts  of  jungle  soil,  2 parts  of  well  rotten  sieved  cattle  manure  and  1  part  of  fine sand. 

 

 

 

 

 

       At  the  time  of  transplanting  it  is  preferable  to  slightly  nip  the  tap  root  of    the  seedling. Transplanting  is  done  preferably  in  the  early  morning  hours  or  late  in  the  afternoon.
Regular watering and after-care of the seedlings should follow. Seedlings  may  be  manured  once  in 2 months  with  urea  dissolved  in   water, 20 g urea  in  4.5 litres  of  water   is  sufficient  for  an  area  of  1 square metre.  Adequate protection is given against nursery diseases and pests.  Overhead  shade  in  the  nursery  has  to  be  thinned  and  finally  removed  after  the  onsets  of  monsoon.
Preparation of land
Clean felling is not advocated.  Selective retention of desired species of wild shade trees is essential. The  land  should  be  divided  into  blocks  of  convenient  sizes  with  foot  path  and  roads laid  out  in between.  In steepy area, terracing and contour planting may also be adopted.
Spacing for arabica and robusta coffee is 1.5 to 2.0m and 2.5m either way respectively and 1mX1m for dwarf variety Sanraman. A close  planting  at 1-1.5 m  either way  and reduce  the population  by  half  after  one  or  two  harvests  is  good. Pits of  45 cm,  are  usually  opened  after  the  first  few  summer shower  and  seedlings  of  16 to 18 months  old  are  planted  during June or September – October. A  hole is made  in  the  center  of  the  pit  after  leveling  the  soil. The  seedlings  is  placed  in  the  hole  with   its  tap  root  and  lateral  roots  spread  out  in  proper  position. The hole is then filled.  The  soil  around the  seedling  is  packed  firmly  and  evenly  in  such  a  way  that  3 cm high above  the ground to prevent  stagnation  of  water  around  the  collar. The seedlings are provided with cross stakes to   prevent wind damage.

Training and pruning
Training  of  the  bush  is  necessary  to  have  a  strong  frame work  which  promotes  production  of  bearing  wood.
Coffee is trained in two systems viz

• Single  stem system

       When  the  plant  reaches  a  height  of  75  cm  in  Arabica  or 110  to 120 cm  in  robusta, lit  is   topped. This helps to restrict   vertical growth, facilitate lateral spreading and increase the bearing area. In  this  system,  a  second  tier  is  also  allowed  sometimes depending  upon the soil  fertility  and plant’ s  vigour.

• Multiple  stem  system

       It is common in Kenya, Tanzania, is not practiced in India. Pruning  in  coffee   is  generally  done immediately  after harvest  and  till  the  onset  of  monsoon. It  is  essentially  a  thinning  process  and  is  done mainly  to  divert  the  vigour  of  the  plants to  certain  parts  by pruning  the  other  parts.  Pruning involves a) Centering   b) Desuckering    c) Handling
Soil   Management
Soil  management practices  aim  at  conserving  soil  and  water  and  in  general  to  make  the  soil  perform its  functions  satisfactorily. It includes the following practices in coffee.

• Digging: In  the  new clearing, the  field  is  given    a  thorough  digging to  a  depth  of  about  35-45 cm  towards  the  end  of  the  monsoon.  All weeds and  vegetative  debris  are  completely  turned  under  and  buried in  the  soil  while  the  stumps  are  removed.  Once the coffee plants have closed in, annual digging is not done.
• Scuffling or  Soil  stirring: In  established  coffee  fields, scuffling  or soil  stirring is  done  towards  the  beginning  of  the dry period .   It controls weeds and also conserves soil moisture.

c) Mulching: Mulching  young coffee  clearings  helps  to  maintain  optimum  soil  temperature  and  conserve  soil  moisture  and  acts  as  an  effective erosion  control  measure  . Mulching also   adds to fertility of the soil.
d) Trenching: Trenches  and pits  are  dug or  renovated  in a  staggered  manner between rows of coffee  along the contour during August-October when the soil  is fairly easy to work. These are 50 cm wide and 25 cm deep and can be of any convenient length.
e) Weed control: New clearings are hand – weeded three to four times a year and established coffee two to three times.  During the monsoon, the weeds are slashed back. Another weeding is done towards the end of the monsoon. Clean weeding is generally done during the post monsoon period. Chemical weedicides have gained popularity in larger plantations. Grammaxone at 1.25 lit in 450 lit of water peer hectare has been found to the best. This should follow weeded plots after 10-15 days.
f) Irrigation: Springer irrigation is mainly used as an insurance against failure of good blossom or backing showers.
g) Soil  acidity  and  liming: The  heavy  rainfall  in  coffee  growing zones  of  South India  brings  about  leaching in calcium and magnesium leading to soil acidity. Besides, continuous use of acid forming fertilizers like ammonium sulphate also makes the soil acidic. Agricultural lime and dolomite lime are the most commonly used liming materials.
Shade and   its management

• Under the climatic conditions existing   in India. Coffee is being cultivated under shade. It comprises of two canopies   lower or temporary and upper or permanent.
• Dadap    is used as a lower canopy shade in India.  Next  to dadap, silver  oak  is  the  most  commonly  used  tree  for  temporary  shade.
• The most   popular   permanent shade trees found in south India. Albizzia lebbec, A.odoratissima, A.moluccana, Artocarpus integrifolia, etc., Permanent shade trees are generally planted about 12 to 14 m apart. The most convenient time to regulate shade is after pruning and liming.

 

 

 

 

 

 

 

 

Manuring
Coffee  plants  produce  every year fresh wood  for  the succeeding crop  concomitant  with the function  of  maturing the current  berries. Hence, they require a regular supply of nutrients. Besides, being grown in heavy rainfall  area, the losses  of  nutrients  due  to  leaching and  fixation  are to be offset by regular application  of  adequate quantities  of  fertilizers.
As  a  supplement  to  soil  applications  of  fertilizers, foliar spraying with  (Urea 0.5 kg, Ammophos (20:20) 0.5 kg  and  muriate  of potash 350 g dissolved  in 200 lit  of water or Bordeaux mixture may be given) during periods of  slow growth, flowering  and  fruit  setting  . However, Bordeaux mixture should be neutralized properly before dissolving the nutrients.
Manurial recommendation for coffee:

	Pre blossom (March)	Post blossom, Pre monsoon (May)	Mid monsoon (August)	Post monsoon (October)	Total
Arabica
1st year	15:10:15	15:10:15	--	15:10:15	45:30:45
2nd and 3rd year	20:15:20	20:15:20	--	20:15:20	60:45:60
4th year	30:20:30	30:20:30	--	30:20:30	80:60:80
Bearing coffee 5 years and above: for less than 1 t/ha crop	40:30:40	40:30:40	20:0:0	40:30:40	140:90:120
For 1 t/ha and above	40:30:40	40:30:40	40:30:40	40:30:40	160:120:160
Robusta
For less than 1t/ha crop	40:30:40	--	--	40:30:40	80:60:80
For 1 t/ha and above	40:30:40	40:30:40	--	40:30:40	120:90:120

Pest Management
Coffee berry borer (Hypothenemus hampei)
Coffee berry borer is the most serious pest of coffee world over. The female beetle bores into the berries through the navel region and makes tunnels in the hard bean and lays about 15 eggs. The larvae feed on the beans, making small tunnels. A typical pinhole at the tip of the berries indicates the presence of the pest, and it damages young as well as ripe berries. In case of severe infestation, 30 to 80% berries may be affected resulting in heavy crop loss. The coffee berry borer can be controlled by the following methods.

a. Cultural
Timely and complete harvest, collection of gleanings, burying the infested berries and maintaining optimum shade and good drainage can control the pest.
b. Chemical
Spraying endosulfan 35 EC 340 ml in 200 litres of water along with 200 ml of wetting agent 120-150 days after flowering (Aug-Sept, for arabica and Sept-Oct. for robusta) can control the pest.
White stem borer (Xylotrechus quadripes)
Plants show unhealthy symptoms like wilting and yellowing of leaves.         As the beetles are active and females lay eggs in the crevices on the main stem of coffee, major efforts to control initial laying of eggs itself is aimed at by swabbing the main stem and the thick primaries with carbaryl 50 WP @ 4 kg in 200 litres of water once or twice (depending upon the severity of the incidence) in April-May or October to December. Apart from this, it is necessary to build up good shade and regularly trace, uproot stump and burn the infested plants. Storing of cut stems is not advisable, as it will advance the flight period.

Shot hole borer (Xylosandrus compactus)
            Attacked plants dry up, extensive tunneling within the branches seen. This is a major pest in robusta coffee affecting the secondary and tertiary branches causing considerable damage. Injury to the coffee plants is primarily by the extensive tunneling within the branches, which limits the flow of sap. The affected branches dry up. The presence of withering and dead branches with shot holes is the symptom of attack.
Control
1. Prune the affected twigs 5-8 cm beyond the shot hole and burn. This operation should commence from September onwards, as soon as the first symptom of attack like dropping of leaves is noticed, and continued as a routine measure at regular intervals.
2. The pest prefers to breed in the suckers during dry period. So remove and destroy all the unwanted / infested suckers during summer.
Mealy bugs (Planococcus sp.)
Mealy bugs damage coffee plants by sucking the sap from the tender branches, nodes, leaves, spikes, berries and roots leading to the debilitation of the plant. In case of root infestation, plants (especially young) become weak, leading to death.
Control
The mealy bug can be controlled by spraying any of the following three insecticides viz. Quinalphos, Fenthion or Fenitrothion. In addition to the above method, the biological control agents like Cryptolaemus montrouzieri (ladybird beetle) and the parasitoid Leptomastix dactylopii have been found effective. Indirect control of the disease can be made by controlling the ants, which spread the infestation.
Green scale (Coccus viridis)
The green scale is a serious sucking pest of coffee particularly arabica.
Control
The chemical control measures include spraying the affected patches with any one of the following insecticides viz. Cythion 50 EC @ 200 ml, Quinalphos 25 EC @ 120 ml, Fenitrothion 50 EC @ 100 ml, Fenthion 1000 @ 80 ml, Methyl parathion 50 EC @ 120 ml or Dimethoate 30 EC @ 170 ml.(Source: Central Coffee Research Institute, Balehonnur, Chikmagalur Dt., Karnataka)

 

 

 

 

 

Disease Management
Leaf rust (Hemileia vastatrix)
            This is an important disease causing economic loss particularly in arabica coffee. On the lower surface of the infected leaves, small pale yellowish spots appear early after the first rains in the season. These spots soon increase in size and number, and many such spots coalesce at severity causing premature defoliation. Severe defoliation leads to debilitation of the bushes and results in poor cropping in the succeeding seasons.
Control
Spray susceptible coffee with 0.5% Bordeaux mixture or 0.03% ai Plantvax 20 EC 3-4 times a year: Bordeaux mixture 0.5% in February-March as pre- or post-blossom spray, Plantvax 20 EC 0.03% ai in May-June as pre-monsoon spray, Plantvax 20 EC 0.03% ai or Bordeaux mixture 0.5% in July-August in mid-monsoon spray (if incidence of leaf rust is severe), and Plantvax 20 EC 0.03% ai or Bordeaux mixture 0.5% in September-October as post-monsoon spray.

Black rot (Koleroga noxia)
A disease more in occurrence in endemic areas with heavy rainfall, saturated atmosphere with 95-100% RH, thick overhead shade, low over-hanging branches, sheltered from sunlight and wind in valleys or continuous mist during monsoon. The affected bushes have blackening and rotting of leaves, twig and developing berries. There will be defoliation and berry drop in the affected branches. The entire block affected looks totally debilitated with heavy damage to crop.
Control
Centering and handling of the bushes prior to the onset of monsoon and protecting endemic patches with spraying Bordeaux mixture 1%. If incidence is observed during the monsoon, remove the affected twigs and burn them. Spray with Bordeaux mixture 1% during break in the monsoon.
Brown blight, twig blight dieback (Colletotrichum glosporioides)
            Small water soaked lesions on margins of leaves and slowly extended causing drying of margins with shedding of berries. Prune badly affected plants during dry months, spray 0.5% Bordeaux mixture.
Harvesting
       Coffee fruits should be picked as and when they become ripe to get better quality. Arabica comes for harvesting earlier since they take 8-9 months for fruit development from flowering while robusta takes 10-11 months. Picking is done by hand. The first picking consists of selective picking of ripe berries often seen in the outer portion of the node and is called fly picking. Thereafter, there will be 4-6 main pickings at 10-15 days intervals and final harvest. Stripping consists of picking of still remaining green berries on the plant.

 

 

 

 

 

 

 

Processing of Coffee

Coffee is processed in two ways a) wet processing to prepare plantation or parchment coffee and b) dry method by which cherry coffee is prepared.
I. Preparation of parchment coffee:
1). Pulping
This method requires equipment and adequate supply of clean water. Fruits should be pulped on the same day to avoid fermentation before pulping. Fruits may be fed to the pulper through siphon arrangement to ensure uniform feeding and to separate lights and floats from sound fruits. The pulped parchment should be sieved to eliminate any unpulped fruits and fruits skin. The skins are separated by pulping should be let away from the vats into collection pits so that microbial decomposition of the skin will not affect the bean quality when it gets mixed up with the bean.
2) Demucilaging and washing
The mucilage on the parchment skin can be removed by
A) Natural fermentation
The mucilage breaks down in the process of fermentation and it takes 24-36 hours for arabica and 72 hours for robusta. Cool weather delays the process of fermentation.  Under fermented or over fermented    beans affect quality. When correctly fermented the mucilage comes off easily and the parchment does not stick to the hand after washing and the beans feel rough and gritty when squeezed by hand. When the mucilage breakdown is complete, clean water is let in and the parchment washed pebble clean with three to four changes of water.
B) Treatment with alkali
Removal of mucilage by treatment with alkali takes about one hour for arabica and one and a half to two hours for robusta. The beans obtained after pulping are drained off excess water and spread out in the wax uniformly and furrowed with wooden ladles with a long handles. A 10% solution of caustic soda (NaOH) is evenly applied into the furrows using a water can.10 litres of alkali is sufficient to treat 25-30 forlits (1 forlit = 40 litres) of parchment. The parchment is agitated thoroughly by the ladles so as to make the alkali to come into contact with the parchment and trampled by feet for about half an hour. When the parchment is no longer slimy and makes a rattling noise, clean water is let in and the parchment washed clean with 3 or 4 changes of water.
C) Removal of mucilage by friction
There are machines, which pulp and demucilage the beans in one operation. However, a number of naked and bruised beans may result in the parchment. It is, therefore, necessary to adjust the machines carefully to obtain uniform pulping and demucilaging. Cup-test results have indicated that there is no difference in cup quality coffee processed by different method.
3. Drying
       The next stage is drying the parchment in the sun until the moisture content is sufficiently reduced to permit storage of beans till they are dispatched to curing works. Proper drying contributes to the healthy colour of the bean and other quality factors. Under dried parchment turns mouldy and gets bleached storage and subsequent curing operations.
The parchment is spread on clean tiled or concrete drying floor to be dried slowly by spreading to a thickness of about 7 to 10 cm. Stirring and turning over coffee, at least once an hour, is necessary to facilitate uniform drying. The parchment should be heaped up and covered in the evening until next morning. Sun drying may take about 7 to 10 days under bright weather conditions. At the right stage of dryness the parchment becomes crumbly and the beans split clean without a white fracture when bitten between the teeth. Drying is complete when a sample forlit of coffee records the same weight for two days consecutively. At this stage, coffee is shifted to the stores and bagged in clean, new gunnies. When coffee is being a dried, all naked bean, pulper nipped and bruised beans, blacks, greens and other defective beans are sorted out and dispatched to curing works separately.
II. Preparation of cherry
For preparation of cherry coffee fruits should be picked, as and when they ripe. Green and under-ripe should be sorted out and dried separately. The fruits should be spread evenly to a thickness of about 8 cm on clean drying ground in which the cherries are stirred and ridged atleast once every hour. The cherry is dry when a fistful of the drying cherry produces a rattling sound when shaken and a sample forlit records the same weight on two consecutive days. The cherry should be fully dry at the end of 12 to 15 days under bright weather conditions.

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1. Coffee was introduced to India by ______________
2. Ploidy level of coffee Arabica is _________
3. Scientific name of tree coffee is _______________
4. What is elephant bean?
5. Botanically coffee fruit is called as _____________

 

 

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