Two and a Bud 58:3-9, 2011

COUNTRY PROFILE

Tea in India: An overview

M. Hazarika1 and N. Muraleedharan2

Tocklai Experimental Station, Tea Research Association, Jorhat 785008, Assam, India

ABSTRACT

Tea is grown in India in a wide amplitude of climatic variables, at latitudes from 8° 12' to 32° 13' N. Currently, anarea of about 579,000 ha is under tea, the major tea growing states being Assam, West Bengal, Tamil Nadu andKerala. Other states such as Bihar, Himachal Pradesh, Karnataka, Orissa, Tripura and Uttaranchal also grow teain small areas. Tea plantations in India are traditionally large holdings but in recent years small scale cultivationhas gained prominence and at present there are more than 200,000 small tea growers who account for 24 percent ofthe production. India is the largest producer and consumer of black tea in the world. Production in 2010 was 966.50million kg of which 80 percent was CTC tea and the remaining 20 percent orthodox, green and other types of tea.The country exported 185 million kg in 2010 which accounted for about 10 percent of world exports. The per capitaconsumption is low, at about 750 g per annum.

Production strategies of the two major tea growing areas of north east India and south India differ due to variousfactors such as soil, climate, plant growth, pests, diseases and cost of production. Harvesting in north east India isconfined to nine months whereas in south India tea bushes are harvested throughout the year. There are remarkablevariations in the chemical constituents of tea leaves due to climatic variables, soils, plant physiology and agro­inputs. This not only invites different strategies for processing' but also for the production of different productcategories. The agronomic practices and processing methods have evolved accordingly. The Indian tea industry ismore than 170 years old and the plantations face several challenges including the geriatric factor. There is stagnationin productivity and no new areas are available for large scale planting. The cost of production is escalating due toseveral factors including the cost offertilizers and pesticides. While India adheres to ISO:3720, there are tea producingcountries which are yet to adopt this standard, leading to the production of substandard tea. The industry in Indiawith the support of the Government has embarked on an ambitious programme of replantation and rejuvenationpruning.

Factory modernization and quality upgradation programmes are in progress. HACCPcertification is widely adoptedby the factories. The industry is supported by research organizations; both in north east India as well as in southIndia and their contributions in the various scientific disciplines have helped the plantations to achieve the presentday productivity and quality.

INTRODUCTION

The story and history of Indian tea industry are asfascinating as the legends associated with the origin andspread of the tea plant itself(Barua, 2008). The tea industryin India is more than 170 years old, since the sending of 12chests of tea, commercially cultivated and manufacturedin Assam, for the London auction in 1838. Approximately,579,000 ha are under tea cultivation in this country and theindigenous varieties of this plant have covered a large partof the tea areas. The major tea growing states are Assam,

I Corresponding E-mail: hazarika50@gmail.com2 muraleedhnair@yahoo.com

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West Bengal, Tamil Nadu and Kerala. Other states such as

Bihar, Himachal Pradesh, Kamataka, Orissa, Tripura andUttaranchal also grow tea in limited areas. Among the teagrowing regions the Brahmaputra basin is the largest.

Production, climate and soil

Traditionally, tea plantations in India are large holdings,but in recent years small scale tea cultivation has gainedmomentum and at present, there are about 200,000 smalltea growers, who account for 24 percent of the production.

India is the largest producer and consumer of black tea inthe world. It has a share of 23 percent of world's teaproduction and 38 percent of black tea production. In 2010,the country produced 966.4 million kg of which 80 percentwas black tea and the remaining 20 percent belonged toorthodox, green and other types of tea. Green tea productionwas 10 million kg. In the past, India had exported as highas 215 million kg of tea, but its share in the, export markethas been dwindling. In 20 I 0, the county exported only 184million kg which accounts for 10.6 percent of the worldexport. Within the country, Assam including Cacharproduces 50 percent of the tea. Dooars, Terai and Darjeelingcontribute 24 percent while south India accounts for 25percent of the production. India is the largest consumer ofblack tea, but the per capita consumption is low at 750 g.Nevertheless, tea is intimately associated with the daily lifeof almost every Indian. It is said that in India tea cuts acrossthe barriers of class. It is a passion with all sections ofsociety, irrespective ofthe social status, income, class, creedor faith. Tea has emerged as the greatest social leveler!(After G.P. Barooah) (Barua, 2008).

In India, tea is grown in a wide amplitude of climaticvariables, at latitudes from 8° 12' N in Nagercoil in TamilNadu to 32° 13' in Kangra in Himachal Pradesh and ataltitudes ranging from near sea level in Assam to 2414 m(7920 feet) above mean sea level (m.s.l) in Korakundha inthe Nilgiris in south India (Source: Limca Book of Records).In north east India tea is planted in the Brahmaputra andBarak Valleys of Assam, plains of Dooars and Terai andDarjeeling hills in north Bengal. The tea soils of north eastIndia have been studied in detail (Anon., 2011 c). InBrahmaputra Valley, it is planted in plain lands at elevationsranging from 50.to 120 m above m.s.l. The valley representsa tectosedimentary province developed during thequarternary period ofalluviation, between the organic beltsofHimalyan foot hills on the north and the Shillong massifin the south. It is formed at stepped sequences of three orfour geomorphic substances, each having steep slop nearthe mountain front which merges gradually in to flat landstowards the river (Bordoloi, 2001). The plains of northBengal were also similarly formed by alluviation in thequartenary period. Tea is planted in a long and narrow tractat elevation ranging from 80 to 300 m above m.s.!., on wellweathered, deep, acidic soil. In the Brahmaputra valley,plantations are mostly on medium texture, sandy loam soil,and heavy soil of sifty loam to sifty clay loam structure.Soils of Do oars are mostly loamy in texture and coarse andsandy. In the Barak valley, tea is cultivated largely onhillocks (teelahs) and on flat land adjoining hillocks andbheels. In the mountainous area of Darjeeling, teaplantations are located at elevations ranging from 600 to2000 m above m.s.!. Darjeeling tea soil is chocolate brown,loam formed in situ. It is shallow and underlaid by stonesand big rocks. The slopes on which tea is grown vary from20 to 300 percent. The average annual rainfall in the tea

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areas ofthe north east is between 2000 to 4000 mm; but ina few pockets it may exceed 5000 mm.

The tea soils of south India extend along the Western ghatswhich run in north to south direction, parallel and close tothe west coast of the peninsula. The six major tea districtsviz the Nilgiris, Anamallais, central and south Travancore,Wayanad, and the High Range vary in elevation from 300to 2500 m above m.s.l. In geological origin, the soils aremainly derived from gneissic rocks, containing lot of mica.The soils have undergone considerable weathering asevident from their low calcium content. The soils are

abundant in sesquioxides. The soils of Anamallais, centraland south Travancore and the High Range are open intexture; coarse and fine sand factors comprising 62 to 67percent of the soil. The soils ofNilgiris and Wayanad areof clay loam type, with the clay fraction prepondering. Thepresence of high organic matter in the soils ofNilgiris offsetthe disadvantages of clay, to a certain extent. All the soilsare distinctly acidic and chemically they are poor, but theorganic matter helps in building structure and microbialactivity (Ranganathan, 1976)

Rainfall in the tea growing regions of south India variesfrom 900 t07500 mm per annum. The western facing of themountain ranges receives the full force of south westmonsoon while the eastern facing gets the full impact ofnorth east monsoon. In between, there are areas whichreceive rains from both the monsoons. The climatic

conditions can be described as tropical to sub tropical atlow and medium elevations and sub-tropical to temperateconditions at high elevations, with distinctly dry wintermonths, followed by one or two dry and hot months, beforethe onset of monsoon. The differences in latitude, altitude,climate and soil ofthe various tea growing areas within thecountry, influence the growth and physiology of the teaplants. The pest and disease complex of the plantations alsodiffer in the different regions (Anon., 20 II a; Muraleedharanet al., 2007)

RESEARCH

Plant improvement and biotechnology

It goes to the credit of the Indian tea industry that it had thevision to create, nurture and sustain tea research

organizations, from the very beginning of planting. Theseresearch organizations, both the Tocklai ExperimentalStation and the UPASI Tea Research Institute have, in turn

contributed significantly to the growth of the tea industry.The biggest research contribution has been the release ofnew cultivars. A major cause for the low productivity inIndia is the age of the bushes and the seedling population.In the early nineties, the technique of vegetative propagationwas standardized and in 1949 three VP clones viz TV I from

Assam-China hybrid population, TV2 from Betjan and TV3

from'Rajgarh population were developed. Tocklai has sofar released 30 TV clones 151 TRA/Garden series clones

and 14 biclonal seed stocks. In south India, the UPASI Tea

Research Institute (UPASI TRI) has released 31 VP clones,five biclonal seed stocks and five clonal graft combinationsfor commercial planting. Besides these, several clones have

, '\' ·been developed by the estates in north east India and a fewin south India. Among these, several clones have thepotential for high yield, good quality, tolerance to drought,pests and diseases. Currently, TRA has over 297 clonesdeveloped by selection, hybridization and tissue cultureunder evaluation from which 10-15 clones are expected tobe released (Das, 2011) Clonal populations though have auniform genetic base, may not be adapted to all types ofsoil and climatic conditions. The genetic base and long termperformance in terms of productivity and quality shouldbe considered for selecting the planting material for anyparticular region. However, it is suggested that no singleplanting material should occupy more than 10 percent ofthe area of the estate.

The industry has initiated an extensive replantingprogramme and therefore, more new cultivars with desirableattributes need to be brought out through selection andbreeding, indeed with the help of biotechnological tools.More than 2100 valuable germplasm having wide range ofgenetic and morphological diversity alongwith some rare,related Camellia species are being maintained at Tocklaiand many clonal cultivars and seed varieties had beendeveloped using these germplasm (Das, 2011) Polyploidy,mutation and tissue culture techniques were employed tosupplement and expedite the conventional tea plantimprovement programme. DNA based genetic markertechniques such as RAPD, ISSR, AFLP, and SSR had beenused for the molecular characterization and documentation

of the genetic diversity of the tea germplasm.Standardization of techniques for genetic transformation,development of linkage maps, expressed sequence tags(ESTS), gene expression profiling etc. are some ofthe areaswhere research had been done in the recent past (Barmanet al., 2011).

Harvesting

The productivity of tea estates is closely related to theefficient and complete harvesting of pluck able shoots andtherefore, harvesting assumes paramount significance in theeconomy of estates. Tea bushes exhibit complete winterdormancy at critical latitude of 16 to 18° north or south ofthe equator. In the tea area of north east India winterdormancy lasts for about 10 weeks. It has been documentedthat in winter, the growth promoting hormones likeGA3"IAA and Kinetin drop to a great extent but the ABAlevel goes up very high, thereby altering the balance ofthese growth promoting and retarding substances in favourof dormancy (Barman et aI2002). Due to winter dormancy,bushes are plucked only for about nine months in north

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east India, whereas in the south harvesting is done roundthe year, the sound Indian tea areas being located between8° 12' and 13° 33 'N. Harvesting is a highly labour intensiveoperation and 60 to 70 percent of the labour force in anyestate is employed for this work. While in north east Indiahand plucking is the norm, in the estates in south India thereis widespread usage of hand held shears for harvesting,due to an acute shortage of workers in the estates, especiallyduring the high cropping months of April, May, Septemberand October. It has been proved that an integrated systemof harvesting, involving the use of shears in the highcropping season and hand plucking during the low croppingmonths is suitable for the estates in south India. (Sharma et

ai, 1981, Satyanarayana and Sharma, 1994)

Recently, Saikia et at. (201 I) studied the effect of continuousand intermittent shear plucking on yield and quality of tea innorth east India. They suggested adoption of shear harvestingduring the peak cropping season of July to September andhand plucking in the remaining months. It has come to astage wherein shears alone are not sufficient to complete theharvest in time and therefore, motorized harvesting machineshave been introduced in certain estates in south India. Victor

Bango et al. (2001) evaluated these machines in fields plantedin different styles and slopes to assess their impact onparameters such as area covered, plucking average, bushphysiology and quality of made tea. They recommended thatan integrated schedule of harvesting using both one man andtwo men operated machines may be implemented in fieldswhich are more than 18 months from pruning. However, theycautioned against continuous machine harvesting becauseof its adverse impact on bush physiology and crop production.Motorized harvesters had been tried in north east as well but

the results were not encouraging (Dutta, 1956; Anon., 20 II b).

Nutrient and water management

Soils and climate of north east India and south India differ

vastly and the manuring practices in both the regions haveevolved accordingly (Anon., 2011 d, Verma et at., 200 I,Venkatesan, 2006). An integrated nutrient managementsystem involving the use of organic manures, biofertilizersand synthetic fertilizers is the need of the hour. Foliarapplication of major, secondary and micronutrients havebeen recommended in both the regions. In this context, itwill not be out of place to mention the extensive work doneon water management in north east India. While floodingand water logging are the limiting factors in theBrahmaputra plains, soil erosion and land slides are themain problems in Darjeeling and the hills of Barak Valley.In the plantations located at the Himalayan foot hills andTerai area, flooding, gully formation and river erosion arethe major causes of concern. The use of remote sensingtechnique on a GIS platform had been proved to be aneffective diagnostic tool for covering large areas of thewatershed basin (Anon., 2011 e). A satisfactory fielddrainage system with adequate outfall is required for the

disposal of excess water from the soil and to prevent waterlogging. Drainage problems in the gardens in comparativelyflat lands have increased over the years due to variousfactors. The extensive work done on this aspect has beenof considerable help to the plantations (Dey, 1981; Ghoshet al., 1984; Anon., 201Ie).

Irrigation has the potential to increase crop in the gardenslocated in the drought prone areas or those with lowmoisture holding capacity. Both drip irrigation and sprinkleirrigation have enhanced crop production during the dryweather period in south Indian tea plantations. Sprinklerirrigation at 6.25 cm at 20 days interval had been foundbest in central Travancore. Drip irrigation with fertigationachieved 46.40 percent increase in crop during soil moisturestress and 24 percent increase in the entire experimentalperiod. (Siby Mathew and Achuthan, 2009). A long termstudy had revealed the details of water requirement,frequency of irrigation and the resultant crop increase inthe Nilgiris (Venkateswaran and Radhakrishnan, 2006)They had also reported (2011) a 40 percent crop increasedue to drip irrigation when the drought was severe.

The soil under tea, over a long period of time, undergoesdeterioration in relation to its structure and nutrient status

(Dey, 1966). Accordidng to Dutta (1956) an area ofuprooted tea should not be replanted in the same year. Forimproving soil aggregation, growing of deep rooted grasseshad been suggested and Tripsacum laxum (Guatemala grass)was found useful for rehabilitation of the soil. Rehabilitation

adds organic matter and improves soil structure. This resultsin better aeration and storage of moisture as well asincreasing the activities of microorganisms imd movingnutrients from deep layers to the top of the soil. The benefitsof soil rehabilitation were more pronounced in heavytextured soil compared to the light textured areas. However,no definite trends in bulk density, base saturation, cation

exchange capacity, pH, microbial load, AI3 and otherchemical properties were evident in the soil of rehabilitatedarea in comparison to that of the directly planted area(Phukan et at., 20 11).

The productivity of plantations are largely influenced byweather factors. Prolonged drought leads to death of plantswhile excessive rainfall leads to floods and land slides

resulting in the loss of plants. Dry weather conditions favourthe build up of pests like mites and thrips while prolongedand untimely rainfall affect crop production by hinderingsunlight and by increasing the incidence and severity ofdiseases like blister blight, grey blight and black rot andthe insect pest, tea mosquito (Muraleedharan, 2008). Ananalysis of rainfall at Tocklai indicated that for the last 30years, the decline in rainfall had been at a higher rate withmore abrasive trends. The recent abrasions in rainfall in

2009 and 2010 led to severe drought and floods,

significantly affecting crop yields in many places (DebBarua and Bhagat, 2011).

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Pest and disease management

The diversity of pests and diseases affecting tea is enormous.While a few have local significance, several are widelydistributed and cause enormous crop loss. Tea mosquito andred spider mite infest tea in all the areas; loopers, red slugand termites are more localized in their distribution. Thrips,jassids and scale insects are occasional pests but causeconsiderable loss in crop.

Among the diseases, blister blight deserves special mention,in view of the loss it causes in south India and Darjeeling.Recently, grey blight caused by Pestalotropsis theae, hasemerged as a serious disease in south India. This woundpathogen gains entry through the cut leaves and stems inthe shear or machine harvested fields. Black rot and red

rust are the major disease problems in north east India.

In the control of pests and diseases synthetic pesticidescontinue to playa major role. However, many parasitoidsand predators exert a natural control of teas pests (Das,1974, 1979, Muraleedharan et al., 1988, 2001)Entomopathogens such as Beavaria bassiana andPaecilomyces jumosoroseus are recommended for thecontrol of shot hole borer and red s-:-ler mite, respectively.Metarhizium anisopliae and Paecitol .yces lilacinus havebeen found effective against livewood eating termites.Nuclear polyhedrosis viruses inflict heavy mortality ofloopers especially Hyposidra talaca, H. inflxaria andBuzura suppressiaria (Antony et at., 2011, Sinu, et. at.,

2011). Semiochemicals are increasingly being used inintegrated pest management programmes. Attempts hadbeen made to isolate the female sex pheromones ofHelopeltis theivora (Sudhakaran et at., 2000) and theKaromones of Euwallacea jomicatus from the partiallydried stems of Montanoa bipinnatifida (Sachin et at., 2007).Botanical pesticides form yet another tool of IPM. Neembased formulations and neem kernel aqueous extract(NKAE) have been proved effective against certain teapests. Combination of extracts of neem and pungam(Karanj) was found effective against spider mites.

Fungal pathogens are generally controlled by the use ofsynthetic fungicides. But recently, there has been extensiveuse of fungal antagonists, especially against pathogensinfecting roots and stems of tea plants. Trichodermaharzianum is effective against Poria infecting roots andstems, while Gliocladium is antagonistic to Poriahypolat£!ritia as well as to Fomes noxius (Premkumar etat., 2009, Borthakur and Dutta, 1992).

Pesticides, when appl ied on tea bushes leave their residueson made tea and different countries including India havetheir own regulations on the maximum residue limit (MRL)of pesticides in tea. A survey on pesticide residues in southIndian tea samples revealed that only 0.5 percent of thesamples had residues of pesticides and all of them were

below the MRL stipulated by the European Union(Seenivasan and Muraleedharan, 2011). Data have also beengenerated on the degradation of pesticides on tea, grownunder different agro-climatic conditions. Manikandan et at.,2009 studied the leaching of residues from black tea tobrew and pointed out that the brew factor should be takeninto consideration for fixing the MRL of pesticides on tea.

Tea chemistry and processing

Chemical characterization ofCTC tea from north east India

revealed that tea from Brahmaputra valley and Dooarsregion is better than that of Barak Valley because of theirhigh contents of theaflavin (TF), thearubigin (TR), totalsoluble solids (TSS), and lower crude fiber content andbrightness (BR). The residual catechin content of black teafrom Dooars and Barak Valley was higher which indicatedincomplete oxidation of catechins to TF and TR duringfermentation (Bhuyan et at., 2009). Long term study onthe biochemical characteristics of south India CTC black

tea showed that the tea produced in Nilgiris, Anamallaisand Karnataka was better than that produced in centralTravancore, High Range and Wayanad in terms of high TFand better TF to TR ratio. There was significant correlationof biochemical quality parameters with organolepticevaluation (Senthilkumar et ai., 2011). Technology forproduction of tea based products such as tea colour, teaflavour and tea tablets had also been developed (Bhuyan etal.,2009).

Transfer of technology

Transfer of technology from the laboratory to the field andfactory is achieved through an efficient system of Advisoryservice. As a part of this service training courses, lectureclasses and field and factory visits are conducted.Publication of scientific articles and advisory circulars alsohelp the extension service to reach out to the plantingcommunity. The system ensures an efficient transfer oftechnology leading to improvements in agronomic andprocessing practices, resulting in increased productivity andsuperior production of superior quality tea.

CONCLUSION

The Indian tea industry today faces several challenges. Nearly50 percent oftea bushes in the plantations are more than 50years old. This geriatric factor leads to stagnation or declinein productivity. Also, new areas are not available for largescale new planting. Besides the ever increasing cost ofproduction, there is stiff competition from other beverages,especially from soft drinks and energy drinks to which theyounger generation is more attracted. While India adheresto the ISO 3720 standards for tea there are countries which

are yet to adopt this standard, leading to the production ofsubstandard tea which adds to the supply chain.

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However, the Indian tea industry with the support of thegovernment has embarked on an ambitious programme forreplantation and rejuvenation pruning. Factorymodernization and quality upgradation programme are inprogress. HACCP and ISO certification are widely adopted.It is an undisputed fact that the Tea Research Institutes havecontributed significantly to the growth of the Indian teaindustry. Nevertheless, the research organization must takein to account the new challenges faced by the industry andreengineer their research programmes.

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