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2019
Samson Kamunya, Simon Ochanda, Evelyn Cheramgoi, Richard Chalo, Kibet Sitienei, Ogise Muku, Wilfred Kirui and John K. Bore Kenya Agricultural & Livestock Research Organization 2/28/2019
Tea Growers Guide
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Tea(Camelliasinensis(L.)O.Kuntze)ProductionandUtilizationinKenyaDr.SamsonKamunya,Dr.SimonOchanda,Dr.EvelynCheramgoi,Dr.RichardChalo,Mr.
KibetSitienei,Mr.OgiseMuku,Mr.WilfredKiruiandDr.JohnK.Bore ThemajorteavarietiesgrowninKenyaare:
1. Camelliasinensisvar.sinensis2. Camelliasinensisvar.assamica3. Camellia sinensis var.
cambodiensis
ChinaryAssamicaCambod
IntroductionTeawasintroducedtoKenyain1903atLimurubyRightBrothers.In1924commerciallargeestatesstartedteafarming.TheTeaBoardofKenyawasformedin1950toregulatetheteaindustry.In1954smallholderteacultivationcommencedundertheSwynnertonPlanwiththefirstsmallholderteafactoryestablishedinRagati,NyeriCountyin1957.In1960SpecialCrop Development Authority (SCDA) was established and two years later, Kenya TeaDevelopment Authority was established under the Agriculture act (cap 318) section191(legalNoticeNo.42).In1999KTDAorderwasrevokedthroughthelegalnoticeNo.44asaresultofrecommendationofsessionalpaperNo.2of1999henceKenyaTeaDevelopmentAuthoritywasprivatizedgivingrisetoKenyaTeaDevelopmentAgencytoservetheinterestofsmallholderteafarmersinKenya.Teathereforecontributesimmenselytosocio‐economicdevelopmentofthecountry.Itistheleadingforeignexchangeearneramountingto20%ofthetotalforeignexchangeearningsandcontributing4%oftheGrossDevelopmentProduct(GDP). Itprovides livelihoodandsupports0.64millionKenyansandcontributes to ruraldevelopment(Ref).ThishasbeenrealizedthroughactiveroleplayedbyalltheactorsintheteaindustryinKenya.ResearchanddevelopmentintheteaindustrythroughKALRO‐TeaResearchInstituteplaysakeyroleinimprovingproductivityperunitareabyavailingcost
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effective and sustainable tea technologies such as proving novel tea cultivars to thestakeholdersinKenya.ResearchinteawasinitiatedbyBrookBondLiebigCo.LtdwithintheAfricanTeaHoldingsLtdinKerichoCountyin1949.ThisservedthewholeofKenyanteaindustryandlatertheEastAfricanregion.In1951thedepartmentwastakenoverbyEastAfricaTeaGrowersandrenamedTeaResearchInstituteEastAfrica(TRIEA)whichregisteredinTanzaniain1959andUgandain1977.TheTRIEAcollapsedwiththebreakupofEastAfricacommunity(EAC)in1977andin1980,theGovernmentofKenyathroughTeaBoardofKenyatookovertheinstitute and established Tea Research Foundation of Kenya (TRFK). In July 2014, theinstitute was renamed Tea Research Institute (TRI) under the Kenya Agricultural andlivestockResearch organization (KALRO) following the state corporation reformprocess(Ref).TeaisoneofthecropsselectedforrealizationKenya’sTheBig4Agendasincetheyear2017.
Fig1:MatureteafieldreadyforpluckingBotanyofteaTeaisaheterogeneousevergreenplantwithmanyoverlappingmorphologicalbiochemicalandphysiologicalcharacteristics.ItfallsundertheTheaceafamillyintheCamelliagenusandisnamedCamelliasinensis,consistingoftwomainvarieties;var.sinensisandvar.assamicaknowngenerallyasChinaandAssamvarieties,respectively.AthirdvarietyconsideredtobeasubspeciesofCamelliaassamicanamedCamelliasinensisvar.assamicaspplasiocalyxhassemierect leavesandisclassifiedasologophite(leafangle50°‐70°).TheChinavarietieshavesmallerectleavesandareclassedaserectophiles(leafangle<50°),whiletheAssamvarieties (considered small trees thought originally to have grown in the forest) havehorizontalandbroadleavesandareclassifiedasplanophile(leafangle>70°).Teacangrowintoatreeattainingaheightof20‐30mifunprunedandcanhaveverylonglifespanofmorethan1,500years(Ref).Theteaplantisextensivelycommerciallyexploited.Onaverageateabush under optimum Good Agricultural Practices (GAP) can produce up to 3.5kg greenleaf/bush/year.
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PropagationTeaiscommerciallypropagatedbyvegetativematerial.Teaplantscanberaisedfromseed,cuttings and tissue culture (micro propagation). Propagation from seed is less commonnowadays following development of operationally easy, rapid and cheap techniques ofvegetative propagation (VP), which facilitate easy production of cultivars. However, ifrequired, open pollinated seeds can be supplied from tea breeding seed barriers. Tissuecultureisrapidandeconomicalonspace.However,itiscostlyforuseinmicro‐propagationandisappropriatemainlyforbreedingpurposes.
Fig 2:
Teaseeds Fig3:Teatissueculture Fig4:TeaplantfromcuttingNursery:Sleevenurseriesarerecommendedforraisingvegetativelypropagatedmaterials.The factors to be considered in site selection include: The closeness of the nursery to apermanentsourceofwaterandtheavailabilityofshelterfromprevailingwind.Availabilityofdeepfreedrainingsoil,friableandwithpHrangeof5.0‐5.6whichisconsideredidealfornurserypropagation.Avoidanceoflowlyingareawhichbecomesverywetduringtherainorwhichgetfrostduringdrymonths.Sleevesof250gaugewithawidthof10cmordiameteroflayflat5.25cmand25cmlong.Mix8wheelbarrowsofsubsoil/topsoilmixturewith¼kgofDAPfor1200sleeves.Thesleevesarefilledtodepthof17‐17.5cm(bottom¾ofsleeve)withsubsoil/topsoil+fertilizermixture.Theremaining¼ofsleeveistoppedupwithsubsoilonly.Packingof thesoilshouldbe fairly firm; itshouldnotbe loosenorshould itbepackedhardandshouldbedapalways.Careshouldbetakenintoconsiderationinselectinghealthyandvigorouscuttingsfrommotherbushesfornurserypropagationthathavebeenlefttogrowfreelyfor5to6monthsafterpruning.Thepropagatedmaterialsarereadyfortransplantingforaperiodof8to12months.Sleevedplantsarereadyfortransplantingwhentherootshavereachedthebottomofthesleevesandalsohaveatleast20cm(8in)oftopgrowth.Selectionof cuttings: Care should be taken into consideration in selecting healthy andvigorouscuttingsfrommotherbushesfornurserypropagationthathavebeenlefttogrowfreely for 5 to 6 months after pruning. The mother bush selected ought to be of apredeterminedcultivar formotherbushes.Prunemotherbushes twiceayeareven if thecuttingsareneededonlyonce.Prunebyastraightnormalcut‐acrossmethod,about2.5cmabovethepreviouspruninglevelor40cmifthebusheshavenotbeenprunedbefore.Cleanout(removeweakandcrossedbranches)onlyonceayear,duringoneoftheprunes.Newshootsarereadyforcuttingsbetweenfiveandsevenmonthsafterpruning.Neverallownew
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stemstoremainonthemotherbushformorethansevenmonthsasthematerialbecomeshardandtheresultingcuttinggrowpoorly.Donotcovermotherbushesafterpruning.Applytwiceasmuchfertilizertomotherbushesaswouldbeappliedtopluckedbushesofthesameage(i.e.rate300kgN/Ha/yr).Applythefertilizerinatleasttwodozeseachyear.Iftheyareprunedeveryfivetosevenmonths,applytwoorthreemonthsaftereachpruning.Takebackbranchesandshootmaterialleftoverafterthecuttingshaveprepared,tothemotherbushesasmulch.Preparationofcuttings:Wrapcutbranchesorcuttings(whips)forcuttingsinwetsacking,taketoshelternearthenurserywaterimmediately.Makecuttingundershadeandshadedat every stage. Use only vigorous young shoots between five to sevenmonths oldwhenmakingthecuttings.Discardtheverysofttipsandtheveryhardlowerpartsofthebrancheswherebarkisforming.Eachcuttingshouldconsistofasingleleafwith3to4cmofstembelowtheleaf.Preparecuttingsusingverysharpknives.Soakcuttings,immediatelytheyareprepared, in a container full of fungicidemancozeb (e.g.Dithane, Emthane) for about30minutes,beforeplanting.Cuttingswithdamagedleavesshouldnotbeused.Plantingcuttings:Theleaforthebudmustnevertouchthesoil(plantcuttingsinthesleevessothatbudisjustabovethesoillevel).Incaseswherethecuttingsleavesarenaturaldeflexed(bendingbackwardsinsteadofupwards),thestemsshouldbeinsertedintothesoilatananglesothatleavesareclearofthesoil.Duringplanting,fingersshouldnottouchthetoporbottomcutsofthestemsasthesweatfromthefingersmayaffectsurvival.Thecuttingshouldbe keptmoist during planting by frequentwatering.Watering should be done gently asstrongjetsmaydisplacecuttings.Stretchtheclearpolythenesheeting(250‐500gauge)tautoverthehoopsandbury1ftdeepintothesoil,toexcludeanyexchangeofair.Nurserymaintenance:Inspectallbedsatleastonceaweek,checkforweedgrowth,insectpests’diseasesandtreatasnecessary.Alwaysweedbyhandpulling.Duringdryweather,keepthesoilaroundthepolythenedamp.Waterthebeds21daysafterplantingorwhenthesheetisnoteddry.Regulateshadedependingontheprevailingweather.Shadeshouldallow50%oftheincomingsunlight.Alternatively,UVnetsarerecommendedforefficiencyandcanbereusedforlonghenceveryeconomical.Hardening offprocess:About 3 to 4 months after propagation (new shoots are about20cmcc),loosenthepolythenesheetingatbothendsofthebedandleavingthepolythenesheetinglooseontheground.Oneweeklater,rollthepolytheneupatbothendsandleaveitthatwaysothatairmaycirculatefreely.Afteranotheroneweekrollthepolythenesheetingupto30cmateachendandaweeklaterrollitup120cmateachend.Increasethisweeklyopeningby1.2mperweekuntilthewholebedisuncovered.Donotallowthesoiltodryupduringthehardeningoffprocess.StartfertilizerapplicationaftercompleteremovalofthepolythenesheetbymakingweeklyapplicationofNPK(S)fertilizerinsolutionformof1g/m2ofnitrogenin1.3lLofwater(10gNPK(S)in10Li.e.1tablespoonofNPK(S)in10Lwateringcan.Followwithan immediateapplicationofwatertowashthefertilizersolutionoff theleavesofyoungplantstoavoidscorching.Plantsarereadyfortransplantingtothemainfieldwhentheyare8to12months.
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Fig5:Teanurserysoil Fig6:sleevebeingfillingwithsoil
Fig7:Sleevesfilledwithsoilreadytoplant Fig8:Plantingteacuttinginsleeves
Fig 9: Cuttings being covered with polythene Fig 10: VP materials ready for fieldtransplanting
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Accesstoteaplantingmaterial(Sites):TheVegetativelypropagatedmaterialorcuttingforownnurserypropagationcanbesourcedfromKALRO‐TeaResearchInstitute,KerichoCentre for the stakeholders in theWest of Rift Valley region and KALRO‐ Tea ResearchInstitute,KangaitaCentrefortheEastofRiftValleyregionasindicatedinthetablebelow:
Table2:LocationofNurseriesPropagatingtea
Region Location Contacts
1 Western KALRO‐TeaResearchInstitute,Kericho
P.O.Box820–20200,Kericho
2 Eastern KALRO‐TeaResearchInstitute,Kangaita
P.O.Box987–10300,Kerugoya
KALRO‐KenyaAgricultural&LivestockResearchOrganization
SomeofthelatestreleasedteacultivarsbyKALRO–TeaResearchInstituteavailableforstakeholdersforcommercialutilizationwiththeirspecialattributes.
TRFK 306
Special attributes•Anthocyanin-rich (purple pigmentation) – medicinal tea product•Drought, frost, disease and pest resistant•Yield potential similar to the high yielding standard check and commercial clone TRFK 31/8•Wide adaptability and suitable for all designated tea growing regions•Suitable for extraction of high quality tea seed oil•Released in July 2011
TRFK 704/2
Special attributes• Low caffeine• Drought, frost, disease and pest tolerant• Yield potential similar to the high yielding standard check and
commercial clone TRFK 31/8• Low catechin content – low astringency• Wide adaptability and suitable for all designated tea growing
regions• Suitable for high quality green orthodox or CTC tea • Granted protective direction certificate in 2014
TRFK 371/8
High Yielding (3 Kg/bush/year) High black tea quality under hand and machine harvesting Moderate to poor fermenter: good for processing of green tea Moderately tolerant to drought effects High levels of theaflavins (TF) and thearubigins same as TRFK 6/8 Medium-high levels of total polyphenols: 22.5% Highly tolerant to root knot nematode Suitable for silvery tips (white tea) Wide adaptability Granted provisional release in 2015
TRFK 597/1
Special attributes• Low caffeine (< 2.0%)• Drought, frost, disease and pest tolerant• Yield potential similar to the high yielding standard check and
commercial clone TRFK 31/8• High catechin content – suitable for catechin tablets & capsules• Wide adaptability and suitable for all designated tea growing
regions• Suitable for high quality black orthodox or CTC tea
G t d t ti di ti tifi t i 2014
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CropManagementSiteselectionandotherbasicconsiderationsAmongthetropicalcropsthereisnonethatdemandssuchpreciserequirementasteadoesif optimum yield is to be obtained. Tea requires a climatewith specific limits of certainattribute;asoilwithspecialcharacters,aproperclearingandpreparationoflandpriortoplanting. It is therefore of paramount importance that in selecting a site for tea, dueconsiderationshouldbegiven toclimaticandsoil requirementsof the teaplantbeforeadecisionismadeonwhethertheareaissuitablefortea.Apointtorememberisthatteaonceplanted,couldlastforforupto100yearsandbeyond.Tearequiresrainfallof1200mmto2200mmthatiswelldistributedthroughouttheyearandtemperaturesrangingfrom13⁰Cto30⁰Cwithoptimumof30⁰C.Analtitudeof1500to2250metersabovesealevelisidealfor tea cultivation. Wind breaks reduce the speed of wind thereby decreasing loss ofmoisturefromsoilbyevaporationandfromtheplantsbyevapotranspiration.Theeffectiveheight of trees should be 10m tall and belts of trees should be 85m apart. Treesrecommended for windbreaks are Hakea saligna, Grevillea robusta using trees and teahedgescanalsobeusedtosheltertheteabushes.Teadoeswellinwellindeepwell‐drainedredvolcanic(minimumof2metreor6 feetdeep)withsoilpHrangeof4‐5.6.Tea issoilspecific,andrequiresacidsoil,humidenvironmentanddoesnottoleratelongdroughtswiththebestqualityteabeingproducedathighaltitudesthatremainfreefromfreefromfrost.CropCareshouldbetakenduringlandpreparationtoremoveallforesttreesbyringbarkingtoavoidarmillariarootrotdisease.FieldPlantingSleevedplantsarereadyfortransplantingwhenrootshavereachedthebottomofsleevesandalsohaveatleast20cm(8in)oftopgrowth.Atthetimeoftransplanting,thecylinderofsoilinsleevesshouldnotbedry.Theplantsmustbehandledcarefultoavoidcrackingthecylinderthecylinderofsoilandperhapstherootsandtheyshouldbestackedcarefullyandtightlyonanyvehicletakingthemtothefield.Anumberofcontainerscanbecarriedonawheelbarrow.Thisavoidsallunnecessaryhandlingof the sleeves.The sleeves shouldbeprotectedfromdirectsunshineatalltimesuntilplantingiscompletedtopreventdamagethe roots. Theholes should be 15cm to 20 cmdeeper than the sleeves anddouble theirdiameter,thoughtheminimumshouldbe25.Forstandard25cmlongx6.25cmdiameterthesleevestheholeswillbe40cmx25cm.Use15gmDiammoniumPhospate(DAP)/Triplesuperphosphateperplantingholeor30gmofsinglesuperphosphate.Mixfertilizersthoroughlywithsoilfromplantingholes.FERTILIZERSFORYOUNGANDMATURETEAFertilizersformotherbushes
Theseareteabushes,whichareusedasregularsourcesofcuttings.Removalofnutrientsfrommotherbushesisatamuchgreaterratethanfrompluckedtea.Bushesweakenedbylackofnutrients(orbecauseofpests,diseases,hail,drought,cold)produce lesscuttings,which strike less easily and grow more slowly in the nursery than those from bushes
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producingvigorous shoot growthafterpruning.Motherbushes shouldbegiven twice asmuch fertilizer,of thesamekind,peryearasapplied topluckedbushesof thesameage.Applythefertilizersinatleasttwodoseseachyear.Thesecanbemadetwoorthreemonthsaftereachpruning.Whenafewbushesareprunedeachdayfertilizercanbeappliedtoeachbush immediately it ispruned. If it isanticipated that twoor threemonthsafterpruningtherewillbenorain,thenthefertilizershouldbeappliedimmediatelyafterpruning.
Fertilizerplacementinplantingholes
Transplantsestablishandgrowfasterifsuperphosphateismixedwiththesoilintheplantingholes.Singlesuperphosphate(SSP)ispreferabletodoublesuperphosphate(DSP)becauseitcontainssulphur,andshouldbemixedwiththesoilatrateswhichvaryaccordingtothesizeoftheholes,asfollows:
Plantinghole(DepthxWidth)
Useeither:
SSP TSP DAP
45cmx22.5cm 30g 15g 15g
50cmx25cm 40g 20g 20g
60cmx30cm 54g 27g 27g
Mixfertilizersthoroughlywithsoilfromplantingholes,onallsoilsexceptonveryrichandhutsitesoils(pH5.7andabove).Soilspreviouslyundergrassorunfertilizedarablecropsrequirenitrogenandphosphate,hencediammoniumphosphate(DAP)shouldbeusedinsteadofsingleordouble/triplesuperphosphate(TSP).DonotuseNPKS25:5:5:5onitsownintheplantingholes.
FertilizerforinfillsForquickinfillestablishment,nitrogen,phosphateandpotashfertilizersmustbeusedintheplantingholeinproportiontothesizeofthehole.Forahole60cmdiameterby60cmdeep,use115gDAPand115gsulphateofpotash(SOP).ThreemonthsafterplantingapplyNPKS25:5:5toeachplanttoeachattherateof50gperplantandthereafterasappliedtotherestofthefield.
Fertilizersforyoungtea
Youngteaisteaofanyagefromthetimeoftransplantingtothetimeofpruningattheendofitsfirstcycle,afteraboutthreeyears’plucking(totaloffiveyears).Inthesefiveyears,theplants need nutrients to maintain their health and extra fertilizer to encourage thedevelopment of strong root and branch systems,whichwill support vigorous cropping atmaturity. The fertilizer should be a compound ormixture providing N, P, K and S in theproportions5:1:1:1,ormoreconcentratedinPandK.Youngteamustbekeptclearofweedsandothercropsgrownintheteaareprovidedwithfertilizeradditionaltothatappliedtotea.Anyconvenientnitrogenousfertilizershouldbeappliedbroadcasttothesoilsurface,soastoprovidenitrogenattherateof12kg/ha,immediatelybeforemulchisfirstappliedtoafield.Thisistocompensateforthetemporarylossofnitrogenfromthesoilwhilethemulchbreaksdown.
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1styearapplication
Sleevedclonalplantshaveleafshootsandactiveroots,andcanrespondtofertilizersappliedas early as six weeks after transplanting. Delay beyond this time can reduce the growthpotential of the plants, but the growth of plants of this age can also be checked by ‘overapplications’ofevenaslittleas36gofNPKfertilizerappliedasasingledose.Theplantsshouldthereforebegivensmallbutfrequentapplicationsof1.5gnitrogen(6gNPK(S)–1sodabottletop)perplantstartingatsixweeksafterplanting.Repeatatabouteightweek(twomonth)intervals.
Donotapplyduringperiodsofdrought.Spreadthefertilizerroundeachplantinabroadring,neverlessthan10cmwide.Fertilizermustnottotouchtheplant'sstem,andtheringshouldthereforebeextendedfrom5cmfromtheplantstemtojustbeyondthespreadoftheshoots.Dribblethefertilizerintothesoiltoadepthof5cm.Ifnecessary,movebackanymulchsothatthefertilizercanbeapplied,andreplaceitafterwards.
2ndyearapplication
Inthesecondyearafter transplantingsleevedplantswillbenefit fromhavingseveralsmallapplicationsratherthanasinglelargeapplication.Thisshouldbeappliedinfourdoses(every3months)aspertheratesshownbelow.
spacing kgs/ha kgs/acre gms/plant
4”X2” 160(3bags) 65(1.3bags) 12
4”x2.5” 160(3bags) 65(1.3bags) 15
5”x2.5” 160(3bags) 65(1.3bags) 19
Donotapplythefertilizerduringperiodsofdrought,anddonothavelessthaneightweeksbetweentwosuccessiveapplications.
3rdyearapplication
Applyinasingledosebybroadcastingintheinter‐rowspacesasperthefollowingrates:
spacing kgs/ha kgs/acre gms/plant
4”X2” 720(14bags) 292(6bags) 54
4”X2.5” 720(14bags) 292(6bags) 67
5”X2.5” 720(14bags) 292(6bags) 84
4thyearapplication
Applyinasingledosebybroadcastingevenlyoverthesurfaceintheinter‐rowspacesaspertheratesbelow.
spacing kgs/ha kgs/acre gms/plant
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4”X2” 920(18bags) 373(8bags) 68
4”X2.5” 920(18bags) 373(8bags) 86
5”X2.5” 920(18bags) 373(8bags) 107
Inthefourthandfifthyearsareaswithasinglerainyseasonthefertilizercanbegiveninasingleapplication,preferablyatthestartoftherains.Inareaswithtwodistinctrainyseasonsitispreferabletogivetwohalf‐applications,oneatthestartofeachrainseason.Donotapplyfertilizerduringperiodsofveryheavyrainfall,assomeofthenutrientswillbelostbysurfacerun‐off.Thefertilizershouldbebroadcastoverthesoilsurface,avoidingtheareaimmediatelyaroundtheplant'sstems.
MatureteaTeabecomesmatureafter1st initial pruning and application is given in a singledosebybroadcasting evenly over the soil surface in the inter‐row spaces at the rate of 150kgN/Ha/yrasshownbelow:
spacing kgs/ha kgs/acre gms/plant
4”X2” 600(12bags) 243(5bags) 45
4”X2.5” 600(12bags) 243(5bags) 56
5”X2.5” 600(12bags) 243(5bags) 70
CAUTION:Donotapplyfertilizerduringdrought.Applyonlywhenthereisrainorwhereirrigationisavailable.
Inthethird,fourthandfifthyearsiftheplantsaregrowingveryvigorously,theapplicationscanbeincreasedaccordingtotheobservedvigourofthetea,to800kg/ha(16bags),1000kg/ha(20bags)and1200kg/ha(24bags)respectively.Largerapplicationsthanthesecanbemadeiftheteaplantsaregrowingveryvigorouslyoriftheplantsaregrowinginsoilswhichhavebecomeimpoverishedbecauseoferosion,lackoffertilizerinearlieryears,croppingwithotherspeciesbeforetheteawasplanted,grazing,oralonghistoryofbeingunderuncultivatedgrass.Inboththesesituations,theamountscanbeincreasedbyabout25percentinthesecondandsubsequentyears.
NOTE:10kgNitrogen=4/5bagsofNPK(S)
Typeoffertilizer
TheInstituterecommendstheuseofafertilizerformulaapproximatingto25:5:5:5,asthebasisofamature‐teafertilizerprogramme.Thisformulamaybeachievedby:
(1)Useofacompoundfertilizer
(2)Mixturesofstraightfertilizers
(3)Alternatingcompoundswithstraightfertilizers.Thismaybedoneeitherwithinanannualprogramme,or incertaincasesonacyclebasis.Asanexample,thecompoundfertilizer
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20:10:10maybeusedtosupplyhalfthenitrogenrequirement,withsulphateofammoniatosupplythebalance.
Itisemphasizedthateconomicconsiderationsshouldbetakenintoaccountwhenmakingsuchdecisions.
Timeofapplicationoffertilizers
Teaunderseverenutritionalstressshouldreceiveacurativefertilizerapplicationassoonaspracticable. If nitrogen is the deficient nutrient, fertilizer application shouldwait until thegrowercanbesurethatrainwillfollowwithinafewdays.Phosphateandpotassiumfertilizersrunlittleriskoflossbychemicalorbiologicalmeansiftheyremainonthesoilsurfaceindryweather.Normalfertilizerapplicationsshouldavoidprolongedcoldorwetseasons,andiftheyaremadeduringdryweathertheyshouldbedelayeduntilitappearsthatrainwillfallwithinafewdays.
Thefirstapplicationinapruningcycleshouldbeatthetimeoftipping,whetherthenormalfertilizerorasupplementaryfertilizertoremedymilddeficiencyisconcerned.Itisassumedthat all pruningswill be left in the field anddecomposingpruning‐leaf and soft twigswillreturnnutrientstothesoil,makingitunnecessarytoaddtothisbeforetipping.Thereisalsoriskofthenitrogenousfertilizercomponentsreactingwithfreshmulchresultinginloweredefficiency of this nutrient. The more highly weathered mulch at tipping time could beconsideredtobesaferinthisrespect.Timingofthelastapplicationinacyclewoulddependontheanticipatedcroppingpatterninthelastfewmonths.Anintervaloflessthansixmonthsbeforepruningmaybetooshortforfullbenefitofthefertilizertobeshown.Severenutrientdeficiency can retard recovery from pruning. If the cause is detected in time, itwould bepreferabletomakeafertilizerapplicationbeforepruning,ratherthanafter.Thetimeintervalbeforepruningshouldbeseveralmonths,andifthevigourofthebushisverypoor,pruningcouldbedelayeduntilthereisevidenceofimprovedgrowth.Thereisnoevidencetoshowthatheavyapplicationof a fertilizernutrient can improve recovery frompruningonabush inreasonablybalancenutrition.
Practical considerations may overrule some of these suggestions. The first considerationshould always be given to planning a fertilizer programme that allows efficient and evendistributionofthefertilizer.
Split applications: Split applications do not significantly improve yield in mature tea.However,aprogrammebasedonahigh‐analysiscompoundfertilizerplusastraightfertilizercouldconvenientlybeplannedsothatthefertilizerswereallocatedtodifferentseasons.Ifso,itisadvisedthatthemulti‐nutrientfertilizerbeappliedbeforethemaincroppingseason.Ifitcanbeconvenientlyarranged,thesamefertilizershouldbeallocatedtothelastapplicationinacycle.
Splitting the annual fertilizer programme may be adopted in order to lessen the risk ofincreasingalreadyexcessivecropincertainseasons.Ifthisisdone,theoverallefficiencyofthefertilizermaybereduced,intermsofqualityofcropproduced.
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DifferenttypesofblendedNPKfertilizers
DifferenttypesofcompoundedNPKfertilizers
Bio‐fertilizerapplication
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Organicandinorganicfertilizers
Fertilizerapplication
RecommendedPlantSpacingandpopulation:TherecommendedmethodsofplantingareTriangular,RectangularandContourplanting.Table3:PlantSpacingandpopulationSpacing(ft) No.ofplantsperacre NoofplantsperHa4x2 5,379 13,4483x3 4,788 11,97031/4x31/4 4,762 10,0004x21/2 4,000 10,77631/2x31/2 3,510 8,7844x3 3,590 8,975
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4x4 2,692 6,7305x3 2,871 7,179
BringingyoungteaintobearingAny operation designed to shape the plant into a permanent framewhich is low, broad,heavilybranchedandcapableofproducingalargenumberofshoots(teatable),culminatinginahigh leafyield.Thereasonsforbringingyoungteaintobearingare:Tohaveaquick,efficient tea plants with good canopy establishment to support yields. Good systemencourages(Benefits).Leadstofasterfinancialreturnsoninvestmentasitenablespluckingto be started early. Healthy tea bushes that give high yields as soon as possible andsustainablymaintaining this yields. Enable the frame tobe low, strong, andhave a goodspread.Systems of bringing into bearing: These systems have been developed to obtain aformationofgoodpermanentframes.i).FormativepruningIsnotinjurioustorootdevelopment.Decentertheplantat6”(15cm)whentheplantsare12”(30cm)butonlywhenthereareatleastthreeleavesbelow6”.Prunealltheshootsat11”(28cm)whentheyarepencilthick.Prunealltheshootsat16”(40cm)whentheyarepencilthick.Tipinforthreeroundsat20”(50cm).Tip‐inforthreeroundsat50cmbyremovingshootsassoonastheydevelopthreeleavesandabudNB.Thebestsystemdependsonclone,vigor(Vigorousclonesestablishfaster)
Fig11:Formativepruningii).PeggingNolongerrecommendedunlessoldclonalmaterialandwidespacingareused.Newclones;growthhabit iserect;peggingnotsuitableforrapidgroundcover.Peggingis injurioustoplantbranches,predisposingthemtostemandbranchcankers(phomorpsis).Istediousandlabour intensive, Materials not readily available. Is an avoidable management expense.Pegged field reduces plucker productivity (manual andmechanized, due to intertwiningbranches impedinguninterruptedmovement).Theshootsthatdevelopafterthefirst lightprunearebentdownwardswhenare60cmtallandhavedevelopedreddishbark.Theyarepeggedsothattheyradiateoutwardsandupwardsfromthemainstem.Peggedbranchesform the basis of permanent framewhich is added to the vertical shoots from auxiliary
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branches.Auxiliarybudsareencouragedifthetwoterminalleavesandabudareremovedfromthepeggedbranch(removesapicaldominance).Tipping‐inshouldbedoneatlowlevelsothatauxiliarybudsdevelopandcontributetoframeformation.
Fig12:Peggingmethodiii).ContinuousTippingTheprocedureofcontinuoustippingistipat20cmandagainat30cm,and40cmfortworoundsbyremovingshootsthathavedevelopedthreeleavesandabud.Tip‐inat50cmforatleast5roundsbyremovingshootsthathavedevelopedthreeleavesandabud.RegularpluckingfollowsNB: tipped shootsmay be processed if the third leaf is brokenoff and discarded. And iftipping isdelayedat20cm,or if a fewshootshavedeveloped, then theshoots shouldbesnappedatthatheightandnotbrokenoff.
Fig13:ContinuousTippingbeingexhibitedTipping has been shown to be disadvantageous for root development and dry matteraccumulation since it entails removing shoots (three leaves and a bud) of tea plants atgradually increased heights. Root growth is reduced and such plants become droughtsusceptibleindry(marginal)areasiv).FreegrowthHasbeendemonstratedtobenolesssuperiortopeggingorformativepruningintermsofplantgrowth,croppingwillstartlaterasresult.Decentertheplantat6”(15cm)whentheplantsare12”(30cm)butonlywhenthereareatleastthreeleavesbelow6”.Allowtogrow
16
freelyfor18months.Pruneat16inches(41cm).Allowtogrowto20inches(50cm).Tipinforthreeroundsatinches(45cm)thecommencepluckingTheadvantagesoffreegrowthare;Quickgroundcover,deeprootestablishment(Rootgrowthproportionaltoshootgrowth),highyieldsandisdroughttoleranceandCheap.TeapluckingManagement
Fig14:Matureteafieldreadyforplucking Fig15:Maturepurpleteafieldreadyforplucking
Teapluckingistheremovalofthetopmostbudandtendershootsofteaforprocessing.Thismaybedonebyhand,handwieldedimplementsormotorisedmechanicalpluckingmachine.
Selectiveplucking:Theactofremovingonlymaturepluckabletendershootsofteafromthepluckingtable.
Nonselectiveplucking:Theremovalofallshootsprotrudingfromthecanopy.Theseshootscomprisetender,dormant,immature,andmatureandovermatureshoots.
FinePlucking:Removaloftwoorlessleavesandthebud.Thisisdonefortheproductionofveryhighqualityteas.
Coarseplucking:Thisinvolvesremovalofmorethantwoleaves+abudandmaygoupto4leaves+buddependingonfactoryorestaterequirements.Itisdonewhengrossyieldismoreimportantthanquality.
LightPlucking:Theharvestingofonly2 leaves+bud fromshootsprotrudingabove thetable,leaving1leafabovethepluckingtable.Thisencouragesfastertableriseandgiveshighqualityteawithreasonableyieldswhileallowingdevelopmentofthemaintenancefoliage.Frequentlightpluckingresultsinrapidtableriseandcropgoingoutofreachbeforepruningisdue.
Hardplucking:Theremovalofallmatureandimmatureshootsprotrudingabovethetable.Itrestrictsthetableriseanddoesnotallowdevelopmentofnewleavestothemaintenancelayer. It gives poorer quality tea but high yields. Continuous hard plucking causesdeteriorationofmaintenancefoliageduetoageingofleaveswhicharenotreplaced
Bhanji shoot‐A shoot with bud that does not develop into an active terminal bud butremainsdormant.Noapicalgrowthoccurs.
17
Bhanjiformation:Whenterminalbudsofshootsfailtodevelopintoactivebuds.Thiscouldbeduetoadverseweathertogrowth(toohotortoocold),secondarybranchesdevelopingalongsidetheprimarybranchproduceshootswhoseterminalbudsdonotdevelop.
Softbhanji:Youngbhanjishootsthatarejustprotrudingabovethepluckingtable.Thesearenewlyformedandaresoftasthetermsuggests.
Hardbhanji:Theseareoldmaturebhanjishoots.Theyarehardasthenamesuggests.
Reasonsforplucking:Toprovidethefactorywithleafthatissuitableforprocessing.Thegrowermakesmoneywhenhe/shesellsleaftothefactory.Thefactory,afterprocessingtheleaf,makesmoneybysellingthemadeteatoconsumersandteatraders
Pluckingstandard
Depend on factory requirement (KTDA‐2leaves+bud) factory requirement. Thereforegrower/estatehastoprovidethetype(standard)ofleafrequired.Innormalpracticetherearefivetypesofshootsthatcanbeplucked.Theseare:‐Onesoftleafandabud,Onesoftleafandabanjhibud(softbanjhi),Twosoftleavesandabud(rolledleaf),Twosoftleavesandabanjhibud,Threesoftleavesandarolledleaf(nottoexceed25%byweightoftheharvest)
Pluckingisrestrictedtoaboveleafstandardsonlyinordertomaintaingoodqualitymadetea.Restrictingthenumbersofpluckableleavesonashoot,istomaintainhighshootgradecompositionandqualitytea
Fig16:Fieldreadyforplucking Fig17:Twoleavesandabudreadyforplucking
PluckingInterval
PluckingIntervalisthetimebetweentwosuccessiveplucking.Itwilldependupontherateofre‐growthafterthelastplucking.Thegreatmajorityofgrowersmakeaflexiblepluckinginterval as they find that a strict timetable is not practicable. However, a grower maysuccessfullyhaveafixedpluckingintervalofsay9‐10daysandachievethisbyvaryingthesizeofshootspluckedeachtime.Afieldshouldbepickedwhenthereissufficientleaftopick.Duringpeakflushperiodsthepickingintervalwillbeshorterthanduringperiodsoflittleflush
18
Fig18:Graphdepictingtheeffectofpluckingintervalonyield
Methodsofplucking
Pluckingcanbedonemanuallyormechanically(shears,handheldmachine,Bobard)
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19
Fig19:Mechanicalteaharvester
Socio‐economicsofteaplucking
MechanicalVersusHandPlucking
Thereisnosignificantdifferences(P<0.05)betweendifferentpluckingmethodsandyields.PluckingspeeddifferedsignificantlywithmethodsofpluckingBobardbeing3timeshigherthanhand‐heldandmorethan10timeshigherthanmanualHandpluckinghadmostleafcontainingH2+.Mechanicalpluckinghadlow4+>.Bobardpluckinghadthehighestofallthevariousgrades.Thereisnosignificantdifferences(P<0.05)betweenpluckingmethodsandshootgrades
ObjectivesofMechanicalPlucking:Tomaximizeonthe labourforceandreduceonthecostofoperations.Teapluckingisamajoroperationthataccountsforupto70%oftheEstateoverheads.Machinepluckingcanbecheaperprovidedtheleafstandardsaremaintained
20
Fig20:Machinepluckedteafield Fig21:Teaharvester(Mitsubishi‐ModelT320
Fig23:EffectsofPluckingIntervalsonYieldsFig24:EffectsofmethodsofpluckingSpeed
0
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051015202530354045
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BOMBARD
HAND-HELD
MANUAL
21
Fig25:EffectsofmethodsofpluckingonyieldFig26:Effectsofmethodsofpluckingonshootgrades
Teapruning
Thereasonsforpruningofteaare:Tomaintainsizeandform,stimulatevegetativegrowth,keepbush frameshealthy&prevent reproductivegrowthphase (flowering‐seeding)andaccessibilityforplucking.
Requirementsforpruning:Donewhenthepluckingtablesreach120to150cm,within3‐4yearsbutmaybeshorterorlongerdependingonpluckingregime
WhenPruningshouldbedone:Pruningshouldbedonewhenthereisadequatereservecarbohydrates,soilmoisturenotlimitingandwhentemperatureiscool
Typesofpruning
i) Cut‐acrosspruning:Thisinvolvestheremovalofalltheleavesandstemsabovethedesiredpruningheight.Itresultstoslowerregrowthespeciallyinhighyieldingclonewhichhave lowercarbohydratesreserves.Lowpruning(lessthan45cm) leadstoHypoxylonwoodrotinfestation.
ii) Lungpruning:Therearethreetypesoflung‐pruning:Rim‐lung(lungsinperiphery),Centre rim lung (lungs in center),Savani (1/3 of bush unpruned).Alleviate poorrecoveryduetocarbohydratesdeficiency(esp.highyielders),lungsassistprunedteain faster regrowth and improve growth and yield of tipping. Lungs continuephotosynthesizing, thus replenishing starch reserves and yields increasewith thenumberoflungs
Fig27:Lungpruning Fig28:Effectoflungpruningondiebackandyields
iii) Down(Reduction)pruning:Downpruningisdonewhenmaximumpruningheightof28inches(70cm)isreached.Donetorehabilitatemoribundbushes.Dependingonthe plucking frequency, this type of pruning can be done once in 12 to 30 years
y = -9.5x + 51.667R² = 0.9991
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Pruning type
Dieb…
22
(dependingonpruning cycle,3‐6 years). However,most farmers practice it due toinadequate plucking & pruning management. (ignorance/culture).Down‐pruningstimulatesnewshoots,andrenewsmaintenancefoliagefromlowerlevels,lowyieldsduetodown‐pruningteacanlastlong(8‐10years)andlowyieldsassociatedwithdown‐pruningareduetopoor,late,ortotallyfailedregrowth
Prunings
Shouldbeleftinsitutoenrichsoilwithorganicmatter,providemicronutrients(factoredinfertilizer formulation and rate recommendations), reduce water loss (mulch reduceevaporation)andsuppressweeds
Problemassociatedwithpruning
Poorpruning results to largecuts, splits,diebacks,bark injuriesphomopsis .Lowpruningheightsresultstohypoxyloninfestation.Wrongpruningimplements(Knives,Pangas),wrongpruningtimes(anytimeofyear),failuretocoverwithpruning’simmediatelyafterpruning,removalofpruning’sandsubsequentuseasfirewoodleadstoyieldreduction(upto30%reported).
Fig29:PlantsectionhypoxyloninfestationFig30:HypoxylonwoodrotFig31:Infectedonsun‐scotched
MechanizedandHandpruningpredetermineheights
To solve the problem of low pruning heights, one has to adopt predetermine height asfollows:22’’,24”,26’’and28”.28’’isthemaximumheightandafterdownpruningisdoneandnormalcyclestartsagainfrom22’.Eachandeverycycleisanincreaseof2’’.
Economicsofmechanizedpruning
Costcalculations‐oneacre(0.4ha)containing(4306teaplants)
Hand
• Labour=29peopleeachearningKsh.269.00
• Totaloperationcost=Ksh.7801
Machine
• Time:11hrs
Sun scorched
23
• Fuel=11Litresand440mlsof2Toil
• Labour=2people
• Totaloperationcost=Ksh.1893
• Savings75.73%
Advantageofmechanizedoverhandpruning
Mechanical pruning ismore efficient& cost effective than to handpruning, safe guardsagainsttheissuesrelatedto lowpruningsuch incidencesofHypoxyllonSerpens.There isUniformrejuvenation,reducednumberofdie‐backs, fasterandtimesaving.Noeffectsonyieldsandnooperatorinjuries
Tipping‐inafterprune
Theobjectivesoftippingafterpruneare:Toproducelevelpluckingsurfacethatfacilitatesefficientpluckinganddevelopanadequatedepthofmaintenancefoliage.Tipping‐inshouldstartbeforeshootsgobanjhiataheightof25‐30cm.Thebesttipping‐inheightis10cmabovethepruninglevel(usually3monthsafterprune‐dependsonweather&clone).Duringtipping‐in,shootsthathavedevelopedtothreeleavesandabudabovethetipping‐inlevelshouldbepluckedoff at the tipping‐in level, tipping‐in aidsmaybeused.Tipping‐in shouldnot bedelayedsothatbudsjustbelowthetippingleveldoesnotbecomematureandtakelongertodevelopintonewshootsCaution‐Nevertip‐inwithaknife.
Table3:Pests,DiseasesandWeedsofteaandtheircontrol
24
NameofPest/Disease Symptom ManagementRecommendation
Pests
1 Crevice/ScarletMite(Brevipalpusphoenicis)
Affectedleavesturncorkybrownontheundersideofleaves,prematureleaffalloccurs,duringseveredroughtyoungleavesareattacked.
Mainlyadequateteanutrition(Notaboverecommendedratesorbelowornoneatall)
‐Useofresistantclonese.g.clone31/8isclassifiedasresistanttoredcrevicemites‐PruningisoneofthemainculturalpracticePruningcanbedoneifdue
‐whensevere,spraywithOmite(Propargite)at3ml/litreofwater
Note Allow 14 daysinterval beforeplucking
2 Redspidermite
(Olygonnychuscoffeae)
Theuppersurfaceofmatureleavesdarkens,turnsbrownandappearsscorchedleadingtodefoliation.
‐Mainlyadequateteanutrition(Notaboverecommendedratesorbelow/noneatall)
‐Useofresistantclonese.g.‐BBLK152,TRFK6/8andTRFK7/9areclassifiedasresistantortoleranttoO.coffeae
‐Pruningisoneofthemainculturalpractices.Pruningcanbedoneifdue
‐whensevere,spraywithOmite (Propargite) at3ml/litreofwater
25
NameofPest/Disease Symptom ManagementRecommendation
3 YellowTeaMite
(Polyphagotarsonemuslatus)
Young leaves curl inwards, becomedistortedandbrowncorky.
‐Mainly adequate teanutrition (Not aboverecommended rates orbelow/noneatall)
‐Useofresistantclones
‐Pruning is one of themain cultural practice.Pruning can be done ifdue
‐whensevere,spraywithOmite(Propargite)at3ml/litreofwater
4 PurpleMite(Calacaruscarinatus)
Affectedleavesturnpurpleandbronzeincolour.
Mainlyadequateteanutrition(Notaboverecommendedratesorbelow/noneatall)
‐Useofresistantclonese.g.‐BBLK152,TRFK6/8andTRFK7/9areclassifiedasresistantortoleranttoO.coffeae
‐Pruningisoneofthemainculturalpractice.Pruningcanbedoneifdue
‐whensevere,spraywithOmite (Propargite) at3ml/litreofwater
5 SoftScales(Coccusspp.)
‐Leaves sometimes turn black withsootymoundsadants
Pruning can be done ifdue
‐Useresistantclones
‐Use of petroleum oilsprays(itisnotregardedasinsecticide)andissafeontheirnaturalenemies(parasiticwasp
‐In the naturalenvironment,thenaturalenemiescontributeuptoabout10%control.
‐ControlantsbysprayingKarate 2.5WG at 1g per
26
NameofPest/Disease Symptom ManagementRecommendation
litre of water aroundbaseofattackedbushes.
6 CitrusAphid(Toxopteraaurantii)
Brown aphids are found in largenumbersontheyoungestshootsandon the underside of leaves. Theaffectedleavescurlbackwards.
Increasingthefrequencyof plucking and or hardplucking till theirpopulation goes down.Withon‐set of rains, thepopulation will also godown
‐Spray of pyrethrumbased pyrethroidpesticidessuchaspygro,whichhaveverylowpre‐harvestperiod(lessthan48 hours) and areeffective
‐Syrphid flies occurringnaturallyinteafieldsalsoplaya large role in theircontrol.
‐ In severe cases,Sprayaffected parts withKarate2.5WGat1g/litre.
8 Helopelits(Helopeltisschoutedeni)
Dark brown spots appear on theyoungestshootswhenfreshwhichturnsblack and produce leaf and stemdistortionasthegrowingtissueexpands.
‐Useofresistantclones
‐Clearingofbushyareasadjacenttotheaffectedsite
‐Spray foliage withKarate 2.5WG at 1g perlitreofwater.
9 Commoncutworm
(Agrotissegetum)
Stemdamageinnurseriesand
seedlingsfailure
‐Karate2.5WGat1gperlitreofwater.
10 Tobakocrikets(Gryltalpaafricana)
Youngplantsarecutofffromthegroundandtheplantdies
‐chemical baitformulation
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NameofPest/Disease Symptom ManagementRecommendation
11 Beetlechafercrub(Schizonychaspp.)
Leaveswiltandsurfaceofrootisdamagedjustbelowthesoilsurface
‐Extensivecallusgrowth(swelling)aroundandbelowthecollar
Spray holes beforeplanting and the soilaround the bushes withKarate 2.5WG at 1g perlitreofwater.
12 Blackthrips(Heliothripshaemorrhoidalis)
Young leaves stunted and cupped,marginsgetcrackedandturnbrownthenpurple.
‐SpraywithKarate2.5WGat1gperlitreofwater.
‐Practicefineplucking
9 TermitesMicrotermesnatalensis
Pseudoacanthotermes
Plantswiltanddie
‐Stembeneathsoilisring‐barked
‐Entirerootdestruction
DestroytermitenestandremovethetopandtreatwithCyren(Jawabu)at10mlperlitreofwaterortricel480ECat10mlperlitreofwater.Sprayaroundtheplantswithabovechemicals
10 Commoncutworm
(Agrotissegetum)
Stemdamageinnurseriesand
seedlingsfailure
‐Karate2.5WGat1gperlitreofwater.
13 Moleratsandporcupines
Damageteabyfeedingonrootsresultingincompletelydestructionofplants.
‐Trapping
‐Good cultural practices ‐Controlling weed particularlygrassalongtheedgesoffarm
28
NameofPest/Disease Symptom ManagementRecommendation
‐inanepidemicfumigationwithDetia/Phostoxin can beconducted by The TRFKstaff(Licensed to handleRestrictedClasschemicals)
Diseases
1 Armillariarotrot(Armillariamellea)
Reduction in growth, yellowing,prematureflowering,defoliationandeventuallydeath.Atthecollarregionlongitudinal crackingof thestemcanbeobserved.
Killing trees by ringbarking, prior to felling.This is best doneduringprimary landpreparation.
‐Removal of roots andstumps of tree thatmayharbor the pathogen.Done as exhaustively aspossible.
‐Within a field of tea,infected bushes shouldbe removed bythoroughlydigging themout as soon as they arerecognized.
NB: The use of a bio‐control agent(Trichorderma sp.). asintegrated strategy or asubstitute can be done‐‐conduct TRFK for moreinformation).
2 Branchandcollarcankeroftea
(Phomopsistheae)
Declineofthebushoccursduetosectorialdeathoftheprimarybrancheswhichmayresultintheultimatedeathofthewholebush.Cankerlesionsdevelopatthebaseofaffectedplantoronthebranchesorboth.UpperedgesofthelesionsareusuallyheavilycallusedLeavesonbranches/wholebushgirdledbythelesionsturnyellowandultimatelydie.Wherethelesionsgirdlethemainstemthewholeplantultimatelydies.‐Stemcankersandlesionsatbaseofthe
Minimize injuries on thebarkofteabymulchingtoavoid stress due to soilmoisturedeficit.
‐Pruning off badlyaffected branches ofinfectedplantsatleast10cm below the lesions.Prunedbushesshouldbetreatedwithaprotectantfungicide such as the
29
NameofPest/Disease Symptom ManagementRecommendation
brancheswhichfinallyturnyellowanddie.
dithiocarbamates orcopperoxychloride.
‐Sanitation‐theprunedoffbranches should bedestroyedbyburning
‐Useofresistantclones
‐Prompt uprooting ofaffected young andinfilling with resistantclones
3 Hypoxylonwoodrotoftea
(Hypoxylonserpens)
Declineofthebushduetosectorialrottinanddeathoftheprimarybranchesresultintheultimatedeathofthewholebush.The rotten wood bears superficialirregular dark‐grey to black raisedpatches of fructifications (stomata) ofvarioussizes.‐Deadbranchescarrysmallblackpatches
‐Prevent sun‐scorchbyshadingexposedbrancheswithpruningsimmediatelyafterpruning
‐useslopingcutssothatrainwaterrunsoff.
‐Paintwoundswithfungicides
‐Avoidlowprunuingdownpruningisthekeypredisposingfactor.
‐Through adherence tocorrectpruningheights
‐Ensure adequate teanutrition (Not above /below recommended Nrates)‐NB:UseofPotassicfertilizer in alreadyaffected fields makes thebushes withstands thedisease stress (Technicaladviceisrequiredpriortoitbeingadopted)
‐Once the disease isdiagnosed the dead anddying branches must beselectivelyprunedoffrightdown approx. 10cm intothe healthy wood. Afterthe large cuts should bepainted over with a
30
NameofPest/Disease Symptom ManagementRecommendation
wounddressing fungicidesuch as copperoxychloride 50% WP inrawlinseedoil.
‐Carryoutfieldsanitationduringeveryprunebysurgicallypruning‐offtheaffectedbranches,removalfromfieldanddestructionofthesamebyburning.
4 Leafspotoftea
(a)BrownBlight
(Colletotrichumcamelliaemassee)
Attacksnurseryplants Outbreakscancauseseveredamageonlyinthenursery
‐Innursery,usefungicidessuchasdithiocarbamates
‐Treatorattendtothepre‐disposingcauses.
3 (b)GreyBright(Pestalotiatheae)
Thefungus infectsmatureandsenescent(old) leaves of tea, which then formsbrown to grey round to oval lesionsmarked with concentric zonation. Blackfructifications somewhat bigger thanthose of brown blight are produced inconcentric rings on the upper surface ofthe lesions.Undercertaincircumstances,cause twigdie‐backofplucked shoots inthefield.
‐Lighttodarkcirculartoovalbrownpatcheswithgreyishcentreonupperleafsurface.
‐Blackpostulesinconcentriclinesonuppersurface.
Easily accomplished byoptimizing shading andwatering.
‐Controlonlynecessaryifit affects plants in thenursery.
‐Casting of shade byadjacent tall trees onsusceptible mature teahas been noted topredisposethebushes.
‐Use of healthy anddisease free motherbushes. Cuttingsmay bedipped in a fungicidesuspension beforeplanting or sprayed justafterplanting.
‐Predisposing factors:‐mainly too much shadeandoverwateringshouldbe identified andcorrected.
31
NameofPest/Disease Symptom ManagementRecommendation
Weeds
1 Dodder(Cascutajaponica)
Canbecontrolledoreradicatedbypruningofinfectedbranchesandcompleteremovalanddisposalofinfectedhostplants.
Buryingorburningreducesadodderinfestation
Public education isnecessary as a strongearly detection programand a way to limitdispersalactivity
2 Ragworts.(Sceneciospp.)
PlantswithPyrrolizidineAlkaloidswhichareoftoxicologicalconcernandcanleadtorejectionofshipments
Integrated weedmanagementmethods can beemployed tomanage weeds intea. Use ofherbicides is donewhen a field isheavilyinvestedbyweeds which aredifficulttomanage.Preferenceisgivento manual weedmanagement, toinclude uprooting,slashingandjembeweeding.
3 WonderingJew(Commelinaspp.)
Hardtokillperennialweedwithsucculentstemsandleaves.Increasescostofteaproduction
Integratedweedmanagementmethodsasabove.
32
NameofPest/Disease Symptom ManagementRecommendation
4 ButtonweedBorreriaprinceae.
Veryhardtokillperennialcommoninteafields
Integratedweedmanagementmethodsasabove.
5 Couchgrass
TheyarePerennialwhichpropagatethemselvesbyundergroundrhizomesandstolons
Integratedweedmanagementmethodsasabove.
6 Kikuyugrass
(pennisetumclandestinnum)
Perennialwhichpropagatethemselvesbyundergroundrhizomesandstolons
BearingIn Kenya tea is grown in the east and west of rift valley where favorable tea growingconditionprevails.Teabeginbearing3to4yearsaftertransplantingandcontinuebearingforover100years(Fig32).Thiscrophaslargereturnoninvestmentandissoldatthefactorydoorsales,producemarkets,groceryshops,Kenyateapackers(KETEPA),supermarketsandattheMombasaauctionmarket.YieldThesuccessofKenyanteaindustryhasamongotherfactors,beenascribedtodeploymentandleveragingofappropriateresearchanddevelopmentoutputs intheproductionvaluechain.Teaisadaptedtowideagro‐ecologicalzonesinKenya.Theyieldsareinfluencedbyagro‐ecologicalzones,variety,soil‐type,soilnutritionmanagementandcropmanagementpractices. The average yield of 1,500 kg to 3,300kg of made tea per hectare per year(mt/ha/yr)hasbeenrealizedonthelargeestatesandanaverageof600kgto2,300kgmt/ha/yrunderthesmallholderproductionsystemhasbeenachieved.
33
Fig32:MatureteafieldreadyforpluckingMarketingTeaissoldatfactorydoorsales,villagemarketsandgroceryshops,TeaisarealsopackagedandmarketedbyseveralsmallagribusinessesenterprisesinKenyagroceryshops,Kenyateapackers (KETEPA),supermarkets.Mostof the tea (95%) is exportedatMombasaAuctionmarketmakingKenyatheleadingexporterofteaintheworld.GrossMarginAnalysisSmallholderteagrowers’grossmarginanalysisandenterpriseprofitability inKenya.Theyielddifferenceinteaproductivitybetweenlargeestatesandstallholderteagrowerscouldbe attributed to low technology adoption rate, deployment of technologies and socio‐economicconstraints(Table4).
Table4:GrossMarginAnalysisandenterpriseprofitability
Item UnitCost TotalCost %Costpopulationperhactare(1.2x0.60m) 13448 Averageyieldperbushperyear(Kg) 1.2 Totalyieldperhactare/yr‐1(Kg) 16137.6 Teaincome Unitprice(Ksh) Amount(Ksh) 1stpayment 14.50 233,995.202ndpayment 35.00 564,816.00TeaOutputValue(TOV)(Kshs) 798,811.20 Variablecosts(Kshs) Unitprice(Ksh) Amount(Ksh) %Cost
Fertilizer(NPK26:5:5)‐12bags/ha 1800.00 21,600.00 8.8fertilizerapplication4bags/Manday 250.00 750.00 0.3weedcontrol(glyphosate)3ltrs/hax2times 1200.00 7,200.00 2.9Herbicideapplicationlabourcost3ltrs/manday 250.00 500.00 0.2Pluckingcost 12.00 193,651.20 79.0
34
Pruningcost 2.00 21,532.00 8.8VariableCosts(VC)(Kshs) 245,233.20Interest(13.5%VC) 33,106.48 TotalVariableCost(TVC)(Kshs) 523,572.88Grossmargin/year(Kshs) GM=TOV‐TVC 275,238.32Grossmarginperbush/year(Ksh) 20.6
StrategiestominimizeproductioncostTominimizeplucking costwhich account79%of the total cost, pluckers shouldbepaidbasingontheamountofkgpluckedinsteadofdailyrate.Usecosteffectivetechnologieslikepruning and pluckingmachineswhich savesmore than 70%, they are also efficient andfaster.Tominimizeonfertilizercost,applyfertilizeronceperyearinsteadofsplitapplicationwhichentailsextracostintermsofstorageandtherenosignificancedifferenceintermsofyield.Tominimizeonweedingcost,maximizeonplantpopulationcapacityperunitarea,gapsought tobe filledup,oncetheteamatures itscanopycoversthegroundhencezeroweeding cost. Ensure that all prunings are left to rot in situ as it helps insmothering/suppressingtheweedsandreleasessomenutrientsonceitrots.TEAPROCESSINGANDVALUEADDITIONIntroductionGreenandPurpleleaffromthefieldarenormallyharvestedforteaprocessingaerated,non‐non‐aerated,semi‐aeratedteasandPuerh(fermented)teas.Valueaddedteaincludefoodandnon‐foodproducts.Foodproductsincludeflavouredorspicesteas,teabiscuits,cookies,cakesbread,alcoholicbeverages,non‐alcoholicbeverages,icecream,andyoghurtsamongothers. Non Food products include, soaps, hand washes, detergents, shampoos, hairconditioners, lotions,creams,mouthwashese.t.c.Teaextractscanalsobemadefromthevarious teas processed from green and purple leafed teas. Thus several areas of valueaddition options on tea are available for adoption by various manufacturing sectors(Ochanda,2010;Ochandaetal.,2011).Theycanbebroadlycategorizedintothefollowinggroups;TeatypesbasedonprocessingstepsTeaProcessingAlthougheachtypeofteahasadifferenttaste,smell,andvisualappearance,teaprocessingforallteatypesconsistsofsimilarsetofmethodswithonlyminorvariations.Teaprocessingoperationsinclude;
PluckingTea leavesand flushes,preferablya terminalbudandtwoyoung leaves,arepicked fromCamelliasinensisbushes.Pluckingisbyhand(Fig.33)ormachine.Thepluckingfrequencyandseasondependsontheregionwheretheteaisgrownandonthetypeofplucking(Li,2007;Luoetal.,2008;Senetal.,1983).
35
Fig33:Harvestingofgreenleafteafromateafieldbyhandpuckers
Withering/WiltingThetea leavesbegintowiltsoonafterpickingandenzymaticoxidationgraduallysets in.Withering is important in removing excess water from leaves, initiation of oxidation,breakdownof leaf proteins into free amino acids and increasing the availability of freedcaffeinewhichchangesthetasteofthetea(Chan,2006;ChenandLin,2008).Theleavescanbewitheredunderthesunorinacoolbreezyroom(Fig34).
Fig34:WitheringofgreenleafunderinafactoryonwitheringunitswithfansMacerationMacerationwhichisalsoknownasdisruptioncausesbruising,tearingorshreddingoftheleavesinordertopromoteandquickenoxidation.Leafdisruptioncanbedonebyshakingand tossing in a bamboo tray, kneadingor tumbling inbaskets, rolling, tearing, using anorthodox machine and crushing by machinery (Fig 35). Maceration can also be done
36
manually by hand.The leaf cells structures are brokendown allowing the co‐mingling ofoxidativeenzymeswithleafsapandatmosphericoxygensettingoffoxidation(VarnamandSutherland,1994).
Fig35:Macerationprocessusingorthodoxmachine
OxidationOxidation is also referred to as aeration and "fermentation". Tea leaves are left in anatmosphere‐controlled room or chamber where they progressively turn darker throughenzymatic activitywhich transforms chlorophyll and tannins (Fig 36). The tea producerdecideswhentheoxidationshouldbestopped,dependingonthedesiredqualitiesinthefinalteaaswellastheatmosphericconditions(heatandhumidity).Inlightoolong(semi‐aerated)teasoxidationmaybe5‐40%,darkeroolong(semi‐aerated)teas60‐70%,andaeratedblackteas100%.Oxidationisimportantintheformationoftasteandaromacompounds,whichgives aerated tea liquor colour, strength, and briskness. Under‐oxidation/fermentationresults in grassy flavours while over‐oxidation results in overly thick winey flavours(Nabarunetal.,2007).
37
Fig36:Oxidationprocessduringthemanufactureofblacktea
Fixation/Kill‐greenFixationalsoknownaskill‐greenorshāqīngisdonetostopthetealeafoxidationatadesiredlevel.Itisaccomplishedbymoderatelyheatingtealeaves,thusdeactivatingtheiroxidativeenzymesandremovingunwantedscentsintheleaves,withoutdamagingtheflavourofthetea (Fig37). This is accomplished throughpanning, steaming, bakingordrum rolling. InsomewhiteteasandblackCTCteas,kill‐greenisdonesimultaneouslywithdrying(WillsonandClifford,1992).
Fig37:HeatfixationofgreenteausingapanfryerSwelteringSwelteringoryellowingisuniquetoyellowteasinwhichwarmanddamptealeavesfromafterkill‐greenarelightlyheatedinaclosedcontainer,causingthepreviouslygreenleavesto turn yellow.The resulting leavesproduce a beverage that has adistinctiveyellowish‐green hue due to transformation of the leaf chlorophyll. Sweltering for 6–8h at close tohumanbodytemperaturescauseschemicalchangesoftheaminoacidsandpolyphenolsinthe processed tea leaves giving it distinct briskness and mellow taste (Varman andSutherland,1994;ChenandLin,2008).
38
ShapingInshapingalsoknownasrolling,thedamptealeavesarerolledandformedintowrinkledstrips,byhandorusingarollingmachinewhichcausestheteatowraparounditself(Fig38).Therollingactionalsocausessomeofthesap,essentialoils,andjuicesinsidetheleavestooozeout,whichfurtherenhancesthetasteofthetea.Thestripsofteacanthenbeformedintoothershapes,suchasspirals,pellets,balls,conesandothers.Inmanytypesofoolongteas,therolledstripsoftealeafareformedintospheresorhalfspheresbyplacingthedampleavesinlargeclothbags,whicharekneadedbyhandormachineinaspecificmanner(Luoetal.,2008).
Fig38:Shapingofteasbyhandrolling
DryingDryingisdoneto"finish"theteaforsalebyreducingtheteasmoisturecontenttosafelevelsof between 3‐4%. This can be done in amyriad ofways including panning, sunning, airdrying,solardrying,microwavingorbaking(Fig39).Greatcareistakentonotover‐cooktheleaves. Thedrying of the processed tea is responsible formanynew flavour compoundsparticularlyimportantingreenteas(Nabarunetal.,2007;Luoetal.,2008).
39
Fig39:Dryingofteasinelectricallyheatedbaskets
AgingWhileagingorcuringisnotalwaysrequired,someteasrequireadditionalaging,secondaryfermentation(involvingbacteriaandfungi),orbakingtoreachtheirdrinkingpotential.Forinstance,agreenpuerhtea,priortocuringintoapost‐fermentedtea,isoftenbitterandharshintaste,butbecomessweetandmellowthroughfermentationbyageordampness(Fig40).Additionally, oolong can benefit from aging if fired over charcoal. Flavoured teas aremanufacturedinthisstagebysprayingtheteawitharomasandflavoursorbystoringthemwiththeirflavorants(Gongetal.,2000;Zhouetal.,2005;HialandEngelhardt,2007).
Fig40:AgingofPostfermented‐PuerhteaTypesofteasWhiteteaThis type is processed fromnew growthbudswhich have undergoneminimal oxidationthroughslightwitheringbeforedryingbybaking(Fig41).Whiteteaisproducedinlesser
40
quantities than most other teas, and is correspondingly more expensive (Hial andEngelhardt,2007).
Fig41:WhiteteaGreenteaThisteahasundergonetheleastamountofoxidationbyhaltingtheprocessbythequickapplicationofheatafterteapicking,eitherwithsteamordryheat(Fig42).Teamaybedriedasseparateleavesorshapedintopelletstomakegunpowdertea.Variationinfixation,rollinganddryingalterstheflavourofgreenteas(Graham,1992).
Fig42:GreenorthodoxteaYellowteaThisteaisprocessedlikegreentea,butinsteadofimmediatedryingafterfixation,stacking,coveringandheatingoftheleavesinahumidenvironmentisdone(Fig43).Thisoxidizeschlorophyllresultingintoayellowishorgreenish‐yellowtea(Zhouetal.,2005).
41
Fig43:Yelloworthodoxtea
42
OolongteaTea'soxidationisstoppedsomewherebetweenthestandardsforgreenandblacktea.Theprocessing involveswithering,maceration, aeration, drying and grading (Fig44).Oolongteasdifferindegreeofoxidationandshape(ChenandLin,2008).
Fig44:OolongteaproductBlackteaTea leavesareallowed tocompletelyoxidize (Fig45).Green leaf iswithered,macerated,aerated,shaped,driedandgraded(VarnamandSutherland,1994).
Fig45:BlackCTCteaPost‐fermentedteaTheseareteasthatareallowedtoundergoasecondoxidationafterfixationandwhichalsoundergomicrobial fermentation (Fig 46). The group includes teas like puerh, liu'an, andliubaowhicharecollectivelyreferredtoassecondaryorpost‐fermentedteas(Wenetal.,2010).
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Fig46:Puerh(brick)teaFlavouredandconsumerpackagedteasFlavouringofteaswithherbsandspiceslikeginger,lemongrass,rosemary,cinnamon,teamasala;jasmineandpackagingintoconsumerpackagesisaformofteavalueaddition.TheadditionofflavourstoteaincreasesconsumeracceptabilitythuspackersandretailvendorslikeKETEPALtd, Lipton tea, Unilever tea, Ceylon tea, Melvins tea, Everton tea among others haveeffectivelysustainedtheirbusinessesinthisway(Ochandaetal.,2011;Ochandaetal.,2015).
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Table6:KerichoGoldteabrandsSNo. Product Description Type1. Teabags BlackCTCtea
2.
lemonFlavouredtea Greentea
3
JasmineandPassionflavouredtea
Greentea
4.
Mintflavouredtea Greentea
Table7:KETEPAProductsshowingteavalueadditionSNo. ProductName Description Type
45
1. Envelopedteabags
Blacktea
2.
Enveloped teabags
Greentea
3. Non‐envelopedteabags
BlackCTCtea
4.
Looseteabags BlackCTCtea
5. IcedTea Blackicedteareadytodrinkproduct
Teaextracts
46
Extractsfromaerated,semi‐aeratedandnon‐aeratedteascanbemade.Extractionplantsforprocessingteaextractsforuseinfood,non‐food,pharmaceuticalandindustrialapplicationsareavailable.In the food industry the extracts are used as colorants, flavorings and fortifiers. In thepharmaceutical industry the extracts are used as antioxidants and recent research hasshowntheirpotentialforuseasmedicinesintreatmentofcancer,diabetes, inflammationandmicrobialinfections.Non‐food and industrial applications include the use of extracts in the production ofpolyphenolstandards,creams,shampoosandbeautyproducts.CompanieslikeDaminfoodsInternational,FinlaysLimitedandEvertonteaamongothersareinthebusinessofproducingsuchextracts(WachiraandKamunya,2005;Lelgoetal.,2011;Koechetal.,2013;Kerioetal.,2013).Table:CocacolateaproductsfromvariouscountriesoftheworldS/No. Product Description Type
47
1.
Iced teaproduct
Black teaconcentrate
2. Cokeflavouredwithtea
Black teaextracts
3. Assortedreadytodrinktea beverageproducts
Black teaextracts
4. Ready todrinkCocacolaproducts
Green andblack teaextracts
5.
Ready todrink fruitflavoured teadrinks
Organic foodteadrinks
TeafortifiedproductsIndevelopedcountrieslikeJapan,China,USA,CanadaandinsomedevelopingcountrieslikeIndiaandMalaysia,havedevelopedreadytodrinkandeatteafortifiedfoodproducts.These
48
includeicedteas,teasodas,teaalcoholicbeverages,teacandies,teabiscuits,teaseedoil,tomentionafew.TheseproductscontributeimmenselytotherevenuefromteavalueadditionasisevidentfromtheoperationsofcompanieslikeKetepatealimited(table1),Marinetfood,Tenfuteafoods,KerichoGoldDaminfoodsamongothers.(Ochanda,2010;Omondietal.,2013;Kileletal.,2013).Thesecompanieshavealsodevelopednon‐foodproductsincludingsoaps,shampoos,papertowels,lotions,mouthwashes,sanitizers,drugs,fertilizersamongotherswithteaextracts(Koechetal.,2013;Njugunaetal.,2013).Table:AssortedNon‐FoodTeaProductsS/No. Product Description Type1. Shampoo Greentea
2. Handwash Greentea
3.
Showergel Greentea
4. Barsoap Blacktea
5. Lotionandgel Whitetea
49
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