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MACADAMIA NUT (Macadamia integrifolia)

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  • ICAR-Central Agroforestry Research Institute, Jhansi Uttar Pradesh

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MACADAMIA NUT
(
Macadamia integrifolia)
M.K.Verma,AshokYadav,NayanDeepakG.,K.UshaandSunilKumar
1. INTRODUCTION
TheMacadamianut,isknownbyseveral
nameslikeQueenslandnut,Australiannut,
Bopplenut,Bauplenut,popplenut,kindal,
boombera,burrawang (Hardner etal.,
2005) and considered as world finest
nut.TheMacadamianut,M. integrifolia
isarelativenewcomeramongcropplants
oftheworld.Itisthefirstandonlynative
food plant of Australia, which has
achievedthestatusofacommercialcrop.
Maximum commercial development has
takenplaceinHawaiiduringthelast60
years(Sharma et al.,2015).Itismainly
grown in tropical climates ofAustralia,
Brazil, Indonesia, Kenya, New Zealand
andSouthAfrica.AmongtheseAustralia
is the largest producer of Macadamia
nuts;whereas, nutinthe Hawaiiarethe
mostdelicious in taste and their delicate
flavourand crunchytexture makesthem
a delight to consume. It is a dark green
spreadingsemihardwoodtreeandcangrowupto20meters(Duke,2001).Nutritivevalue
of macadamia nut has been presented in the Table 1.
Macadamia nuts are world’s most delicious nut with small in size, crispy buttery
flavoured nuts. Apart from being delicious, these nuts are good sources ofprotein and
minerals with sweet in taste and can beeaten either raw from the shell, dryroasted or
28
CHAPTER
CONTENTS
1. Introduction............................................... 583
2. History,OriginandDistribution.................584
3. AreaandProduction ................................. 585
4. Taxonomy ...................................................585
5. Species......................................................586
6. Cultivars .................................................... 588
7. Propagation ............................................... 591
8. Cultivation .................................................592
9. QualityCharacteristicsand
MaturityIndices........................................ 601
10. Harvesting ..................................................601
11. Yield .......................................................... 601
12. PostHarvestManagement ........................ 602
13. ValueAddition ...........................................603
14. TradeandMarketing .................................603
15. EffectofClimate Changeon
MacadamiaNut .........................................604
16. FutureResearchPlan................................ 605
17. OrganicCultivation....................................605
584MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
cookedinoil.Macadamianutsareahighenergyfood,commonlyusedinpreparationsof
cakes, confectionery, ice cream, salads, roasts and casseroles to enhance the savour.
Macadamianutsareoneoftheonlyfoodsourcesthatcontainpalmitoleicacid.Palmitoleic
acidis abeneficiaryfattyacid,found higherinhumanliver.Theseacidincreasesinsulin
sensitivitybysuppressinginflammation,aswellasinhibitsthedestructionofinsulinsecreting
pancreatic beta cells.
Table1: NutritivevalueoftheMacadamianut
Nutrient Value Nutrient Value Nutrient Value
Energy 718Kcal Pyridoxine 0.275 mg Man ganese 4.131 mg
Carbohyd rates 13.82g Rib oflavin 0.162mg Phosphorus 18 8mg
Pro tein 7.91g Th iam in 1.195 mg Se len ium 3.6mcg
TotalFat 75.77g VitaminA 0IU Zinc 1 .30mg
Ch olesterol 0mg VitaminC 1.2mg Sodium 5mg
DietaryFiber 8.6g Vitam inE 0.24 mg Po tassium 368mg
Fo late s 11mcg Calc ium 85 mg Ph ytost erols 116mc g
Niacin 2.473 mg Copper 0.756 mg ßsitosterol 108mcg
Pantothenicacid 0 .758mg Iron 3.69mg
Source:USDANationalNutrientdatabase(www.nutritionandyou.com)
2. HISTORY, ORIGIN AND DISTRIBUTION
The macadamia nuthas originatedinAustra lia, morepr ecisely in the rain forests of the
southeastern Queensland and northeastern New SouthWales whereas he present day
macadamia nut iscreditedtohave developedin Hawaii,andfromtherethecropfurther
movedtoEastAfrica.Isolatedtreeof thisnutarefoundinnumberofsoutheastAsian
countries.Inthe1850’s,aGermanAustralianphysicianandbotanistcalledFerdinandvon
Mueller discoveredthemacadamianutanddecided toname thegenus after a colleague.
His name was John Macadam. Von Mueller was a noted chemist and physician who
encouraged macadamia nut cultivation. The macadamia genus consists of eight species,
twoofwhichproducenutswhichareaviablefoodsource.Thisgenus offloweringtrees
isfoundinthefamilyProteaceae,andmostofthemactuallyproducepoisonousorinedible
nuts.TheyaremainlyfoundinAustraliawitha species ortwo growinginIndonesiaand
New Caledonia. Macadamia nuts trees were imported to Hawaii for cultivation in the
1880sfor growingasawindbreakandlaterin1930;itscommercialpotentialfor dessert
nut was developed by university of Hawaii. Nowadays, most macadamia plantations
thriveinHawaii.ItisdistributemainlyintropicalclimatesofAustralia,Brazil,Indonesia,
Peru,Fiji,Kenya,Israel,Colombia,Venezuela,NewZealand,SouthAfricaandTanzania.
MACADAMIANUT585
3.AREAANDPRODUCTION
PresentlyAustraliaandHawaiiarethelargestproducingareasofmacadamiawithothers
including eastern and southern Africa, and Central and LatinAmerica. Northern New
South Wales and southeastern Queensland are the region having high production of
macadamianutsinAustralia.Hawaiiaccounting70percentoftotalmacadamiaproduction
worldwidefollowed byAustralia, around22percent, rest isproducedbyother countries
including Malawi,SouthAfrica, Kenya, Guatemala, Mexico, Brazil, Costa Rica, New
Zealand, CaliforniaandChina.
4.TAXONOMY
It belongs to the family Proteaceae of which about 1000 species exist including the
Banksias, Grevilleas, Stenocarpus, Dryandra, Hakea and Telope (Mc Conachie,
1980~ BenJeecov and Silber, 2006). Proteaceae, isan ancient angiosperm family whose
initial differentiation from ancestral forms occurredin the southeast ofAustralia 90100
millionyearsago.Thefamilyiswellknownforother generasuchasBanksia, Grevillea,
andHakea. Proteaceaeappeartohave been a majorcomponentof theearlyangiosperm
dominated rainforests whichonce covered most of Australia. Macadamia were probably
widelydistributedwithintheseearlyforestsasevidencedbymacadamiatypefossilpollen
recordedinsedimentsinsoutheastAustralia,centralcoastalQueenslandandNewZealand.
Kingdom: Plantae
Phylum:Magnoliophyta
Class:Magnoliopsida
Order: Proteales
Family: Proteaceae
Genus: Macadamia
Species: (i) integrifolia,
(ii) ternifolia,
(iii)tetraphylla
4.1. Cytogenetic
Allthreespecieshavetheidentical somaticchromosomenumberof 2n=28.Thisreport
was the first on the chromosome numbers of M. ternifolia and M. tetraphylla. These
numbers were determined from root tips of M. ternifolia and M. tetraphylla seedlings,
and from dividing microsporocytes in M. tetraphylla. The chromosome number of M.
integrifolia was first reported by Darlington and Wylie (1955) as 2n = 28 (56), as a
previously unpublished number determined by Ukio Urata of the University of Hawaii.
The 56 in parentheses refers to a clone, Y279, which was discovered to be tetraploid.
Later, Urata (1954) published the numbers as n = 14 and n = 28.
586MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
5.SPECIES
AccordingtoCostelloetal. (2008)thegenusconsistsofninespecies.Thespeciesnative
to Australia are Macadamia integrifolia, M. tetraphylla, M. ternifolia, M. jansenii,
M. whelani, M. claudiensis and M. grandis, whereas M neurophylla is native to New
Caledonia and M. hildebrandii is native to Sulawesi in Indonesia. However, only the
smoothshelled(Macadamiaintegrifolia)andtheroughshelled(Macadamiatetraphylla)
arecultivatedfortheirediblenuts(Peaceetal.,2003)asM.ternifoliaproducestinynuts
witha bitter flavoured kernel(Mc Conachie,1980). The two edible Macadamia species
areclassifiedaccordingtoamongothercharacteristics,numberofleavesinanodalwhorl
(phyllotaxy),leaftype, leafmarginalserrations andcolour of newgrowth(Ryan, 2006).
The Genus Macadamia (familyProteaceae), as presently understood, comprises ten
species of tropical and subtropical evergreen trees (Table 2).
Table2:ListofMacadamiaspecies
S.No. Species Origin
1 M.hildebran dii Steenis Celeb es
2 M.Rousselii(Veill.)Sleumer NewCaledo nia
3 M.ve illardii(Brongn.andGris.)Sleumer
4 M.francii(Guill.)Sleumer
5 M.whelaniF.M.Bail. EasternAustr alia
6 M.ternifoliaF.Muell.
7 M.integrifoliaMaidenandBetche
8 M.tetraphyllaLAS.Johnson
9 M.prealta(F.Muell.)F.M.Bail
10 M.heyana(F.M.Bail.)Sleumer
DescriptionoftheMacadamiaspecies
5.1. Macadamiaintegrifolia (Queensland/Australiannut;bushnut;nutoak;
Bauplenut;smooth shellnut)
Plant: Trees are vigorous with dark green foliage, strong crotches and ascending ra ther
thanspreadingbranchstructure.‘Kakea’aswellas‘Keaau’and‘Kau’,themostrecently
introducedcultivars, havemoreuprightgrowthhabitsthanKeauhouand‘Ikaika’,which
havespreadinggrowthhabits.Amoreuprightgrowthhabitpermitscloserplantingwithin
the row and thus more trees per acre. Individuals are often multi stemmed with small
crowns. Leaves: The simple obovate to narrowly oblong leaves are arranged in whorls
ofthreeoropposite,and5.5cmto14cmlongby 2.5cmto6cmwide(Stanley andRoss,
2002).Bladetipsareroundedandfinishinashortsharppoint~thebasetaperstopetioles
5 to 10mm long. Flowers: Axillary creamy white flowers are arranged in brush like
hanging racemes 10 to 30cm long. Flowering period isAugust to October with kernel
MACADAMIANUT587
maturation from December to March, with mature nuts falling to the ground thereafter.
Fruits: Rounded fruits are green, 2.5 to 3.5cm wide with a hard brown inner shell
protecting the edible nut.
5.2.Macadamiajansenii (Bulburinnuttree)
Plant:The plantaresmall,singleormultistemmedtree69m tall,with generallysmooth
bark dotted with prominent lenticels (Halford, 1997).
Leaves: The leaves are oblanceolate to oblongelliptic and are generally arranged in
whorls of three and 1018cm long with an acute apex, tapered base and wavy margins
(Hardenetal.,2006).Netvenationonleafbladesisdistincton bothsurfaces, especially
when held up to the light. Petioles are 214mm long.
Flowers: Theflowers arecreamy brownishhavingsepalsthatare79mmlong~ flowers
have been observed in July and September.
Fruits:Theglobosefruitare2025mmindiameter.Thekernelismildlycyanogeneticand
notedible
5.3.Macadamiaternifolia(Gympienut,Marcoochynut,Smallfruited
Queenslandnut)
Plant: The trees are perennial with 6 m tall, with brown branchlets dotted with raised
lenticels (Hauser and Blok, 1992).
Leaves: The leavesare simple, narrow oblong to narrow elliptical leaves are arranged
inwhorlsofthree,and1012cmlong~newgrowthispinkishred.Bladetipsarepointed
and the base tapers to petioles 3 to13mm long (Stanley and Ross, 2002).
Flowers: Axillary pinkish flowers are arranged in brush like hanging racemes 420 cm
long.FloweringperiodisAugusttoSeptemberwithfruitingoccurringfromMarchtoApril
(Hauser and Blok, 1992).
Fruits: Compressed rounded fruits are greyish, 1.52cm long with a hard inner shell
protectingtheediblenut.Theseedkerneliscyanogenetic(presenceofpoisonouscyanide
radicals) and not edible.
5.4.Macadamiatetraphylla(Spinyleafmacadamia;roughshell
Queenslandnut;bushnut)
Plant: Tree is a perennial 18m tall, with greyish brown branchlets dotted with pale
elongated lenticels (Hauser and Blok 1992).
Leaves: The simple oblong lanceolate leaves are arranged in whorls of three to four,
620cmlongand24cmwide.Bladetipsarepointed, marginssharplyserratedandpetioles
are 28m long (Stanley and Ross 2002). New leaves of M. tetraphylla are bright red in
colour, whereas those of M. integrifolia are light green.
588MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
Flowers:Axillarypinkishpurpleflowersarearrangedinbrushlikehangingracemes15
45cmlong.FloweringperiodisAugusttoSeptemberwithfruitmaturingandfallingfrom
March (Hauser and Blok 1992).
Fruits: The fruit are compressed rounded with greyish green, 23.5cm wide with a hard
inner shell protecting the nut. The seed kernel is edible and not cyanogenetic.
6.CULTIVARS
6.1. Beaumont(Dr. Beaumont)
It is a hybrid (Macadamia integrifolia x M. tetraphylla) commercial variety, widely
plantedinAustraliaandNewZealand.ThecultivarwasdiscoveredbyDr.J.H.Beaumont.
Itishighin oil,butisnotsweet. Newleavesarereddish,flowersarebright pink,borne
on long racemes. It isone ofthe quickest varieties to come into bearingonce planted in
theorchard, usually carrying a useful crop by thefourth year, and improving from then
on. It crops prodigiously when well pollinated. The impressive, grapelike clusters are
sometimes so heavy they break the branchlet to which they are attached. In commercial
orchards, it has reached 18 kg nuts per tree by eight years old. On the downside, the
macadamias do notdrop from the tree when ripe, and the leaves are a bit prickly when
onereachesintotheinteriorofthetreeduringharvest.Itsshelliseasiertoopenthanthat
ofmostcommercialvarieties.Shellmediumthick,kernel40per centofnut,witha high
percentage of GradeA kernels.
6.2. Burdick
M. tetraphylla. Originated inEncinitas, Calif. Large nut, averaging 40 per pound. Shell
thin,about1/16 inches thick, well filled. Kernel recovery averages about 34 per cent of
total nut weight, quality good. It matures in October. Tree bears annually. Not widely
planted these daysand has been replaced by better cultivars. Also usedas a rootstock.
6.3. Cate
M.tetraphylla.Originatedontheproperty ofWilliamR.Cate, Malibu,California.Nuts
mediumto large.Shellwithaverage thickness.Kernels40percentofnut,creamcolour,
crispintexture,flavourgoodtoverygood.RipensinlateOctoberandNovembercontinuing
over a period of 6 to 8 weeks. Tree precocious, moderately hardy, shows no alternate
bearing tendency. The most widely adapted cultivar for commercial use in California.
6.4. Dorado
M.integrifolia.OriginatedinHawaii.IntroducedbyRanchoNuezNursery.Mediumsized,
uniformnuts,7/8to1inchindiameter.Kernelaverages35percentofnut,oilcontent75per
cent.Treemediumtall,upright,attractive.Beginstobearafter5years,selfharvesting,cold
resistant.Veryproductive,oftenyielding65ormorepoundsofnutsperyear.
MACADAMIANUT589
6.5.Elimbah
Originated in Australia. Imported into California by E. Westree. Thin shells. Kernel
averages4550percentofnut.Thetreehasattractivewhiteflowers,comesintobearing
veryquickly,is veryproductive,andhas arelativelythinshell.Varietyhavetendencyto
drop nuts year round. 
6.6. James
M.integrifolia.OriginatedinLaHabraHeights,California.Mediumsized,uniformnuts,
about 1 inch in diameter. Kernel averages 40 to 42 per cent of nut, quality high, flavor
very well, oil content 75 per cent. Tree very tall, columnar, precocious, often producing
after2or3years.Selfharvesting.YieldsmoreperacrethananyotherCaliforniacultivar,
60 or more pounds per tree when mature.
6.7. Keaau
M.integrifolia.OriginatedinLawaiValley, Kalaheo,Kauai,Hawaii. Medium sizednut,
averagingabout80nutsperpound~Shellsmooth,mediumbrown,thin.Kernel4246per
centofnut,colorlightcream,qualitygood.SeasonAugusttoNovember.Treemoderately
vigorous,upright, veryproductive.
6.8.Keauhou
M. integrifolia. Originated in Kona, Hawaii by W.B. Storey. Medium to large nut,
averagingabout54nutsper pound.Shellveryslightlypebbled,mediumthick.Kernel37
to40percentofnut,qualitytendstovaryindifferentlocations.Harvestseasonrelatively
short,withmostofthecropmaturing within about3months.Treevigorous,yieldswell,
extremely resistant to anthracnose.
6.9. Vista
HybridoriginatedinRanchoSantaFe,CaliforniabyCliffTanner.Smalltomediumsized
nut, 3/4 to 7/8 inch in diameter. Kernel averages 46 per cent of weight of nut, flavor
excellent, oil content 75 per cent. Shell very thin, can be cracked in an ordinary hand
cracker. Tree medium sized, pyramidal, begins to bear after 3 years. Self harvesting.
Flowers pink. Recommended for both home garden and commercial plantings.
6.10.Waimanalo(M.integrifolia)
OriginatedattheHawaiiAgriculturalExperimentStation,Waimanalo,Hawaii.Largenuts,
occasionallywithtwinhalves.Shellrelativelythick.Kernel38percentofnut,flavorgood,
oilcontent75percent.Treemediumsized,pyramidal,productive,beginstobearafter5
years.Producesnutsinlargeclusters.Resistanttofrostanddisease.Growswellincooler
climates, particularly near the ocean. Also yields good crops in the inland.
590MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
6.11. PA39
One7yearoldtreeofthisvarietygave33kg.Thekerneliscleanandattractive.Itgives
95percentGradeAkernel,witha crackoutof40percent.Anothergreat virtueisthat
the nuts drop when ripe. It combines well with Beaumont as a pollinator. It is a small
compacttree,veryprickly,andverysusceptibletogreenshieldbug.PA39isoneofBrian
Piper’s selections.
6.12. GT1
Agoodselforcrosspollinatorwhichcancropheavilywithsmallernutsandmayrequire
extra feeding. The nut is small and of good quality, with a high oil content. The kernel
iscleanandattractive,andthecrackoutishigh.Thetreeislessdenseandpronetowind
damage.
6.13. GT2
AGordonTitirangiselection.Thisnuthas a thinshell,so rat depredationandshield bug
damage are both real problems. Nine year old trees gave 8 kg per tree.
6.14. GT201
A GordonTitirangiselection, usefulas a pollinator for Beaumont, has goodnutquality.
6.15. GT207
AGordonTitirangiselection.Beverlyhasonlyjustplantedthisvariety, has100per cent
grade1 nut at Woodhill.
6.16. Own Choice
AHawaiianvarietyproducesthebestqualitynut.Thecrackoutis32percent.Nineyear
oldtreesproduced22kgpertree,nutsdonotdropwhenripe.Itisagoodpollinatorfor
Beaumont, and appears to be largely self fertile on theirorchard.Another good variety
for the domestic garden with good self or cross pollination, large nuts and few prickles.
Tends to crop inconsistently and year round not of much use commercially.
6.17.Maroochy
A pure M. tetraphylla varietyfrom Australia, is cultivated for its productive cropyield,
flavor, and suitability for pollinating ‘Beaumont’. Seven year old trees produced 75 kg.
6.18. Nutty Glen
AnAustralian hybrid selection. The nut is large and of good quality also popular as a
rootstock.
MACADAMIANUT591
6.19. Nelmac I
It is quite a light cropper, a 10 year old tree yielding an average of 8 kg. It is a month
lateinflowering,whichmaybehinderingitspollination effectonBeaumontanditsown
cropping. However,if thepollination couldbecorrected,itwouldbeaverygood variety
because the nuts drop when ripe. Although the nut is slightly elliptical which makes
cracking awkward, and has a low crack out because of the thick shell, processors like
thisvarietybecauseofthehighqualitykernel.IthasablandtasteliketheHawaiiannuts,
and high oil content.
6.20. Nelmac II
It is apopular variety because of its pollination of Beaumont, and the yields are almost
comparable. It appears tobesusceptibletoiron chlorosis,withbleachedleaves showing
up in ear ly summer when the treeis under stress. It has a sweet nut, which means that
it has to be cooked carefully so that the sugars do not caramelise. The sweet nut does
not tastegood when processed, but people who eat it uncooked relish the taste. The nut
istoobigforprocessors,andhasanopenmicropyle(holeintheshell)whichletsinmould.
The crack outpercentage is high. Ten year old trees average 22kg per tree.
6.21. Renown
A M. integrifolia / M. tetraphylla hybrid, this is a rather spreading tree. It is high
yielding(commercially,17kgfroma9yearoldtreehasbeenrecorded),andthemacadamias
droptothegroundhowever itisthickshelled,andwithnotmuchflavour.Itisoftenused
asparentinbreedingnewvarieties.Itsgoodcharacteristicsincludetheyield(17kgfrom
9yearoldtrees),thefactthatitdropswhenripe,andakernelofquitegoodquality.The
nutiselliptical,soisdifficulttohandleforprocessing.Thecrackoutisonly33percent.
7. PROPAGATION
7.1.Seed propagation
Select fresh, medium sized seeds fromthe elite trees. Soak the seeds in waterfor 1 day
and discard the floating ones. Seedswill germinate after8 weeks of sowing at high soil
temperatures (30 – 35
0
C) and moisture levels (90 %). When temperature falls below
24
0
C,germinationtimeextends.Usesandororganicmatterasmediaforgerminationand
it avoids water logging. Harden the seedlings before transplanting to the main fields.
Seedlings take 8 to 10 years for start commercial bearing.
7.2. Vegetative propagation
Macadamiacanbevegetativepropagatedbybudding,softwoodcutting,airlayeringand
graftingbut,graftingmethodiscommon.Graftingmethodsfollowedaresimplewhip,side
graft,tip,wedgeor cleft.Graftinghas tobedonein springorautumnforbetter results.
592MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
Thescionwoodas M.integrifoliaispreferred forthebestnutsproductionandrootstock
is M. tetraphylla for its resistance to diseases (trunk canker and anthracnose). The
rootstock tobeused forgraftingshouldbeusuallyseedlingsof 912months oldwithat
leastadiameter of11.3cm.Somegrafted varietiesofmacadamiasbeginbearingwithin
2years, while others not before 7 to 8years.
7.3.Micro‐propagation
Tissueculturetechniqueshelpineasyandrapidintroductionofnewvarieties,production
of disease free plants, ease of propagation and uniformity in plants. Micropropagation
directlyfrommeristemofshoottipsandaxillarybudsisusedforregenerationoftrueto
type plant in macadamia nut. Bhalla and Mulwa (2001) developed an efficient micro
propagation system in macadamia nut which would be valuable in facilitating quicker
multiplicationofnewrootstockandscionvarieties.Singlenodesectionsalongwithdormant
axillarybudsweretakenfromthenewgrowthoftwoyearoldgraftedplantsofMacadamia
tetraphylla.AftersurfacesterilisationandcultureinitiationusingMSmediumforexplants
were exposed to different levels of BA (0, 0.5, 1, 2, 4 and 8 mg l
1
). The developing
shoots were subcultured every four weeks and the new shoots exceeding 15 mm in
length were taken for studying rooting experiments and the number of shoots produced
ateachsubcultureintervalwasrecordedtodeterminethetotalnumberofshootsproduced
per explant in every treatment. OptimumBA level (2 mgl
1
) fromthe above experiment
wascombinedwithvarying concentrationsofGA3(0, 0.125,0.25,0.5,0.8and1.0mg
l1) to determine an optimum shoot elongation treatment. The regenerated shoots were
exposedtomediumcontainingdifferentlevelsofIBA(1,2and3mgl1)forrootinduction.
Bud break and shoot numbers were significant reduced in the lowest (0.5 mgl
1
) and
higher (4 and 8 mg l1) concentrations of BA tested whereas budresponse and shoot
growth was recorded highest percentage in the medium containing 2 mgl1 BA. Bhalla
and Mulwa (2001) observed increasein shoot lengths with increasing concentrations of
BAinthemedium.Amaximummeanshootlengthof1.6cmat2mgl
1 BAwasobtained.
These shoots were used for rooting experiments. In vitro rooting experiments showed
very inconsistent results due to high incidences of shoot tip necrosis.
7.4.RejuvenationandTopworking
Thisisusuallydoneataconvenientheight,2to4feetabovegroundlevel.Thisoperation
is done to reduce tree height or to change the genotype with desirable one. Grafting is
followed for top working.
8.CULTIVATION
8.1.Soils and climatic requirements
Macadamia can be grown in wide range of soils but performs well in red soils rich in
manganese with well drainage, deep and fertile (organic matter). Avoid planting in poor
MACADAMIANUT593
drained clay soils. The soil pH of 5– 6.5is suitable for growth and development.Area
receiving60120 inchesof rainfallper yearisidealandcan begrown at anelevationof
15003,500feet abovethe sealevel.Temperaturerangesfrom15
0
Cto30
0
Cisidealfor
plant growth and flower formation occurs at 18
0
C. At higher temperatures decline in
production and quality of kernel deteriorates. At low temperatures vegetative growth is
seizedandifthetemperaturedropsbelow1.5
0
C,thetreesarekilledbyfrost.Treeswon’t
requirechillingforfloweringandaseasonalchangeintemperaturemayhelptosynchronize
bloom.Avoidplantinginextremewindysitesasmacadamiawoodisbrittleinnature.Train
the plants at younger age and use windbreaks like leguminous species or Silver oak to
prevent wind movement. Avoid planting in shady areas.
8.2.Land/pitpreparation
Before orchardselection,soil analysishas to bedoneforbetter orchardmanagement.In
some areas there are serious problem of chlorosis which is caused by deficiency of ca
and phosphate, there is need to correct it. So, if the soils are lacking calcium and
phosphateatinitiallevelduringplanting,thereisneedtoapplylimeandphosphateatthat
timeonly.Soilanalysishelpsincalculationoffertilizerrequirement.Cleartheland,ifslope
istheremake itintolevel. Digthe 60cm
3 pitsthree weeksbeforeplanting.Pits are dug
in September and October.
8.3.Spacing
Planting shouldbe spacedat7mapartwithin rowwith 35 mbetweenrowsfor upright
varieties. For spreading cultivar, planting is done at 10m apart within the row with 6m
between the rows. Spacing also depends on soil, variety, climatic conditions, etc.
8.4.Planting
Remove thetop soil and mix with manure and other required manures. Select healthy
seedlingsfreefrompest,diseasesandabnormalities.Afterplacingtheseedlinginpitrefill
thetopsoilmixedwiththemanuretobottomandsubsoilontop.Addneemorpongamia
cakeintopitwheretermiteproblemisthere.Finallygivestalktoavoiddamagefromwind
and for better standing.Apply water around the plant.
8.5.Trainingandpruning
At early stages training is necessary to maintain good framework for future growth.
Macadamia produces several leaders but, need to leave only strongones and rest has to
be removed. The frame work for a strong, wellbalanced tree can only be established
while the tree is young. Remove shoots growing in rootstocks where grafts are used. It
is desirable to have a spacing of ½ to 2 feet between sets of main branches. Remove
the flowers tillplant attains good stature.
594MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
Pruning of matured macadamia trees is very important to reduce the amount of
unproductivewoodsinturnallowsnewproductivevegetativeflush.Whenpruning,suckers
whichareontherootstockthatisbelowthegraftingunionshouldberemovedduringthe
months ofJuly toAugust. Ifthereis nolateralbranchesaftertwoyears ofplanting, the
head of the tree should be pruned at least 80cm high. Prune the abnormal, pest and
disease infects branches.
8.6. Intercropping
Atearlystages ofplanting intercropscan growinbetween space.Althoughmacadamia
Arabicacoffeeintercroppingunderrainfedconditionshasbeenshowntoproducepositive
results with irrigation(Perdona et al., 2015).
8.7. Irrigation
Properand regularirrigation hastobegivenat earlystages ofgrowthanddevelopment.
Prematurenutdropisamajorprobleminwarmdryregionswhere,hightemperaturewith
waterstress willbethere.ThecriticalstageofirrigationisfromthebeginningofAugust
until the end of November. Over irrigation from May to July may hinder flowering.
Provide timelyirrigation basedonsoilconditionto getquality andquantity yield.
8.8. Weeding
Weeds compete for water, light, space, nutrients and also harbor pests and diseases.
Therefore timely remove weeds either manually or mechanically. By adopting drip or
basinirrigationsystem therewillbereducedweedgrowthandhighwater useefficiency.
8.9.Mulching
Organic and inorganic mulch can be applied but organic one is economical. Mulching
suppresses weed growth, retains moisture, maintains micro climatefor microorganisms
and also acts as cushion while harvesting fruits. Dry and chopped grass, crop residues
andleavescanbeusedformulchingandtheyshouldbeplacedinabasinleavingaradius
of 10 to15cm from the stem and the thickness shouldbe 1015cma gain. Barner grass,
macadamia husks, fowl manure and bagasse mulch were compared in a demonstration
trial under 10yearold trees with macadamia decline symptoms. It showed that
theapplicationofmacadamiahusksresultedinthebestresponseinthetrees,withincreased
root growth and improved tree health (Anon., 2013).
8.10. Frost Protection
Youngtreesaremorepronetofrostthanmatureones.Wraptheyoungplantswithplastic
over a frame around. As the trees get larger, they are more difficult to cover, but they
also become more tolerant of mild frosts.
MACADAMIANUT595
8.11. Fertilizer management
Applyfertilizerafterplantattainingayear,broadcastinthedripareathatis1520cmfrom
the stem. This fertilizer should be applied following rains. In case of non rainy period
artificialirrigationhas tobegivenafterfertilizerapplication.N.P.Kshouldbeappliedin
splitapplicationsparticularlyduringthemonthsofNovembertoDecember.Soilandleaf
analysis provides clear indication of nutrients requirement.
Table3:FertilizerapplicationrecommendationsforMacadamia(g/tree)
Option1 Option2
Ageoftree CAN Triple Muriateof Compound Muriateof
(Year) superphosphate potash (15 520) potash
1 100 2 0 125 185 6 5
2 200 4 0 250 370 130
3 300 6 0 375 555 190
4 400 8 0 500 740 260
5 500 100 625 925 320
6 600 120 750 1,110 380
7 700 140 875 1,295 45 0
8 800 160 1,000 1,480 51 0
9 900 180 1,125 1,665 57 0
10 1,000 200 1,250 1,850 630
11 1,100 220 1,500 2,035 700
12 1,200 240 1,625 2,220 760
13 1,300 260 1,750 2,405 830
14 1,400 280 1,875 2,590 890
15 1,500 300 2,000 2,775 950
16 1,600 320 2,000 2,960 1,020
(Source: Anon.,2012)
8.12.Insect‐pestsandtheirmanagement
Macadamianut isinfestedbyvariouspestduringitlife cycle. Forbettermanagementof
pest,weeklymonitoringofthepestsduringfloweringandfruitingshouldbedone.Macadamia
pests are infesting the tree at three different stages
A. Floweringstage:FlowersaredamagedbyBlackcitrus aphids(Toxopteraaurantii),
Broad mite (Polyphagotarsonemus latus), Blue butterfly (Morpho peleides), and
Loopers (Anacamptodes fragilaria). The pests can be controlled by insecticides
like Endosulfan 35EC, Propineb 50 EC, etc.
596MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
B. Fruit formation stage: At this stage Yellow spotted bug (Bathycoelia rhodaini),
Mosquitobug(Heloppeltisspecies)andCoreidbug(Leptocariasordida)arenoticed.
TheseinsectpestsarecontrolledbysprayingwithEndosulfan35EC,Fenitrothion50
EC, etc.
C. Nut maturity stage: Macadamia nut borer (Cryptophlebia batrachopa), False
codling moth (Cryptophlebia leucotreta), Litchi moth (Cryptophleabia peltastica)
and carob moth (Spectrobates ceratoniae) are important at nut maturity stage. The
pests are controlled by insecticides like Cypermerthrin 20 EC, etc.
8.12.1.Nutborer
Nutborercanboreintothegreenhusksofnutsoritfeedonthekernels.Susceptibilityvaries
incultivarsdependingonhardnessandthicknessoftheshell.Theinfectednutcanbeidentified
byasmallholeinthehusksurroundedbyexcreta.Affectednuts,especiallyyoungdeveloping
nuts,usuallydropasaresultofdamagetothehusks.However,itcanbeavoidbygrowing
fairlyresistantcultivars(Nelmak1,Nelmak2andtheHawaiiancultivars).
8.12.2. Stinkbugs
InAfrica,stinkbugsarethe mostimportantpeston macadamias causinglossesupto80
precent.Thedamageiscausedby20differenttype’sstinkbugsamongthemtheimportant
typesare: twospottedstinkbug,greenvegetablestinkbug, smallgreenstinkbug, coconut
stinkbug,spottedstinkbug,yellowspottedstinkbugandyellowedgedstinkbug.Stinkbugs
can be controlled chemically through cypermethrin and endosulfan. For reduction of the
originalpopulationsizeofstinkbugsprayingofcypermethrinmustbegivenafterflowering.
Majorly stinkbugs have four generations per year and each generation causes a
different type of damage to the nuts.
S.No. Stinkbugsgeneration Occurrence Damageofplantpart
1 Springgeneration AugusttoSeptember Occurduringorafterfloweringand
canc auseextensiveflowerandfruit
drop.
2 Summergeneration Decembe r Itcausesdamageatthetimeoffruit
developmentandjustbeforethefruit
reachestomaturesize.
3 Autumngeneration FebruarytoMarch Itmainlyfeedson then utsbefore
an d dur ing  harve st. Altho ug h it
causeslesionsonthenutkernel,no
fruitdropoccurs
4 Wintergeneration Dec ember endtoJan uary Itd oesn’tcauseprob lemsbecause
mostnutsareharvested,hardness
oftheshellpreventstinkbugfeeding
an d alsotheya re no t veryactive
du ring th isseaso n
MACADAMIANUT597
8.12.3. SouthernGreen Stinkbug (Nezara viridula)
Itsattackleadstoprematurenutdropandkerneldamage.Thestinkbuginserts itshollow
needlelikemouthpartintothenutandinjectssalivaintothekernel.Enzymesinthesaliva
damagethetissuearoundthetipofthemouthpartsandthebugconsumestheliquid.This
feeding activity causes pitting of the kernel. Nuts infested on the ground may also have
white or brown discoloring. The damage can be seen year round but majorly damage is
observed from July to September. The variation in infestations is due difference in
environmental conditions. The stinkbugs reproduction and development stages occur on
theweedswhileitfeedsonmacadamiatreeiftheirprimaryfoodplantsbecomeunavailable.
It can be control by spray of endosulphan and malathion.
8.12.4. Litchi FruitMoth (C. ombrodelta)
It bores into the nut causing premature nut fall and damaging the kernel. Nut quality is
diminished and production is decreased. The damage mainly occurs during the oil
accumulation period whereas the insects are prevalent yearround. Heavy premature nut
drop results from May to mid of the August. It effectively controlled by spray of
Azadirachtin.
8.12. 5. Red‐banded thrips (Selenothrips rubrocinctus)
Itdamagesismainlyrestrictedtotheoutersurfaceofnutshavingnoimpactonmaturation,
nutdrop ornutquality. Insevereinfestationbronzingsymptomappears ontheleaf. Pest
pressures from this pest may be greater at lower elevations. It mainly occurs in end of
theharvest season,butthey arepresentin orchardsyearround. Inthenursery itaffects
thedevelopmentofrootstockandgraftedmacadamianutseedlingsbysuppressingseedling
growth duringthe firstsixmonthswhereseedlingheightwillbe1012 inches tall(when
growth is normally slow). It can be chemically controlled by malathion.
8.12.6. Red& Black Flat Mites (Brevipalpus phoenicis) & Broad Mites
(Polyphagotarsonemus latus)
Thebothflatandbroadmitesareabundantlyfound inmacadamiagrowingareasfeeding
onthefoliage,flowersandnuts.Thedamageflowersandinfestedflowersdonotsetnuts.
Theyaremostprevalentduringgrowthflusheswhichoccurafteraperiodofdryweather.
The infection by broad mites results in silvering of husks whereas flat mites results
bronzing of husks. T hey can be chemically controlled by spaying with Microthiol.
8.12.7. Hawaiian flower thrips(Thrips ha waiiensis)
Itiswidespreadthroughoutmacadamiagrowingareas.Itischemicallycontrolledbyspray
ofMalathion.
598MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
8.12.8.Secondarypests
Inspiteofmajorpests,numerousotherinsectsareassociatedwithmacadamianutproduction.
The secondary pests which are commonly foundin macadamia nut are broad mite, red
bandedthrips,Hawaiianflowerthrips,blackcitrusaphid,katydids,variousscalesandwhiteflies,
and flat mite. The secondary pests’ seriousness varies dramatically in orchards due to
abnormality in cultural practices (fertilizer application and pruning), weather conditions
(temperature&humidity),alternatehostplantssurroundingtheorchard,orpesticideuse.
8.13.Diseasesandtheircontrolmeasures
8.13.1.MacadamiaRootRot(C.O.Armillariella mellea)
Due tothe soil borne nature of fungus, the infectionstarts fromthe root system which
later extends toward upwards resulting into complete deathof the plants. Root rottening
resultsduetocoveringofwhitemycelialgrowthontheroots.Spreadofthediseasefrom
tree totree occurs by root contact. The temperatures varyingfrom 8
o
C to 22
o
C along
with wet soils having a high proportion of woody debris facilitates rapid spread of the
fungus and again. Before digging holes for planting, all woody roots debris must be
removed and burnt.
8.13.2. Blossom Blight (C.O. Botrytis cinerea)
Itisafungaldiseasewhichisprevalentespeciallyinthewintermonths.Highhumidityand
temperatureabout16
o
Cto22
o
Cfavoursthedevelopmentoftheblossomblightdisease.Old
orchardsandhighdensityplantingaremostsusceptiblebecauseofreducedaircirculation.
Theaffectedflowersbecomesblightedhavinggreytobrownishpowderysubstancesanddo
notdevelopintomaturefruits.ItcanbecontrolledbysprayingBenomyl50ECorPropineb
50ECwhichcanalsobeusedwithEndosulfan35ECorEndosulfan47.5EC
8.13.3.Anthracnose(C.O.Glomerella cingulata)
The fungal pathogen mainly affects the leaves, twigs and the nut. Leaves dropping and
die back of the twigs takes place with the advancement of the disease. The disease is
spread by wind and infected leaves and twigs whichfall of the plant acting as a source
ofinoculumsinthefollowingseason.Removingandburningalldeadtwigs,branchesand
leaves may results in control of the disease.
8.13.4.Huskspot(C.O. Pseudocercospora macadamiae)
Initially chlorotic to yellow flecks symptom appear on the husks which enlarge and
develop tan brown in the centres. Later the lesions coalesce and develop diffuse bright
MACADAMIANUT599
yellow halos and may develop inside the husk but shells and kernels remain unaffected.
The spores are spread from infected husks by water splash and diseased husks may
produce spores for up two years. Remove the old and diseased husks from thetree to
reduce inoculum levels.
8.14.Physiologicaldisorders
8.14.1.TreeDecline
Itisamajor disorderin macadamianut. So manyfactorslikelow organicmatter levels
insoil,deficitnutrients,drought,rootexposureduetosoil erosion, rootdeathinshallow
marginal soils, heavy crop loads, pests and diseases are responsible for this disorder.
8.14.1.1.Managementpractices
Good orchard management.
Pruning – Prune affected parts to generate new flush. Apply foliar fertilizers at
regular intervals for new leaves.
Mulching–Basedonavailabilityandcost,applyorganicorinorganicmulchjust50
cmawayandaroundthetrunk.Don’tapplymulchneartotrunkbecausemulchhosts
for pests and there may be chancesof trunk canker infestation and pest attack.
Applyrecommendeddoseoforganicandinorganicfertilizers, andgoforregularsoil
and leaf analysis.
To prevent soilerosion, adapt drip or channel irriga tion system for watering.
Avoid planting inshallow lands or after mounding go for planting.
Regular checking and management of pests and diseases.
8.14.2. Abnormal vertical growth (AVG)
Thecauseforthisdisorderisnotyetunknownmaybeduetogeneticfactor.Thisdisorder
has observed in dry areas of Queensland and New South Wales, and deep well drained
red soils. HAES 344 is the most susceptible variety.
Symptoms – Upright branch growth, reduction in flowering which leads to low yield.
8.14.2.1.Managementpractices
Avoidplantingindryregionsoraftercorrectingthe possiblefactorslikelimitwater
infiltration,water r etentionand root growthgo for planting.
Goforsuitableirrigationsystem.
Avoid planting susceptible varieties or plant spreading varieties.
Maintainoptimumsoilconditions, regularapplicationofmanures andfertilizers.
600MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
8.15.Use of plant growth regulators
8.15.1. Auxin
Williams,(1980)testedforreducingimmaturefruitdropofmacadamiabutnoeffectswere
foundontheinitialorfinalnumbersoffruitsetperracemewhenanauxin,i.e.naphthalene
aceticacid(NAA)wasusedatdifferentconcentration(1,10,or100mgL1
).
8.15.2.Gibberellins
Gibberellins also play important role in flower and fruitdevelopment, and fruits often
contain highlevelofendogenousgibberellinconcentrations(Wilkieet al., 2008;Ayeleet
al., 2010). Trueman, (2010a) found that immature macadamia fruits contain very low
gibberellinlevelsandare,unlikelytorespondtogibberellinsynthesisinhibitors.Fruitdrop
isalsounaffectedbyGA
3 applicationwhichtendstoindicatethat theprocessesinvolved
in macadamia fruit retention are not sensitive to gibberellin concentrations
8.15.3. Cytokinin
Cytokininapplicationtoflowersorimmaturefruitofmacadamiaincreasesinitialfruitset
anddelaysfruitabscission,withoutaffectingfinalfruitset(Trueman,2010).Severalplant
growth regulators have been tested for their ability to reduce abscission of macadamia
flowers and immature fruits but only the cytokinin, benzyladenine(BA), has shown any
promise of increasing fruit retention (Williams, 1980; Trueman, 2010a). The cytokinin,
benzyladenine, increases fruit retention for up to 8 weeks after anthesis but does not
increasefruitsetbeyondthemajorabscissionperiodat10weekspostanthesis(Trueman,
2010a).Endogenouscytokininlevelsareveryhighinmacadamia fruitsaround10weeks
postanthesis,whichsuggeststhatfruitsmaybe,ineffect,cytokininsaturatedandinsensitive
toapplied cytokininsatthisstage(Trueman,2010b).
8.15.4.Ethylene
The benefits resulting from Ethephonreduced harvest lengthand time, lesspressure on
dehuskingshed,lessnutsperharvestroundandimprovedinnutqualityhasbeenobserved
(Jim and Kevin . 2012).
8.15.5.Uniconazole
Nagao et al. (1999) studied the effectof uniconazole (0.2 g a.i. per cm trunk diameter)
on 2 yearold potted macadamia (Macadamia integrifolia Maiden & Betche) trees and
they found that uniconazole significantly reduced tree height and trunk diameter 1 year
after initial treatment, and suppressed shoot extension for the duration of the study. In
caseofflowering,thereissimilarandnormalfloweringintreatedandcontroltreeduring
1
st year but in 2
nd year in treated plant there was increase in flowering as compare to
MACADAMIANUT601
untreated plant. Subsequently, no differences in flowering were observed until the fifth
year,whenfloweringwassignificantlylessintreatedtrees,probablyduetoreducedshoot
and trunk growth and tip dieback.
9.QUALITYCHARACTERISTICSANDMATURITYINDICES
For better quality, macadamia nut kernels should have light cream colour, spherical in
shape, high oil content, free from rancidity, decay, insect damage, blemishes and
discoloration. Highest quality kernels contain 72 to 78 per cent oil and 1.5 per cent
moisture whereas for fully developed macadamia kernels should contain 72 per cent oil
ormore. Oilcontentisamajor qualityfactorwhichvariesfromcultivarto cultivarand
alsowithmaturity.
Aftertheprolongedfloweringseason,macadamianutsarematureoveralongperiod
fromlatesummertolatespring.Kernelsarematurewhenoilaccumulationiscompleted.
The rapid drying, oil content and electrical impedance of the nut are the other maturity
indices of the macadamia nut. Sometimes shakeharvesting is employed to facilitate the
harvest while minimizing the amount of immature nuts are harvested.
10.HARVESTING
Macadamia nuts are mainly ready for harvest during late May to July, but variety to
varietyit varies alsoand it maygo onunto late November. Nuts are picked byhand or
sweptup mechanically from the orchard floor, depending on the variety of tree.A long
polecanbeusedtocarefullyknockdownmaturenutsthatareoutofreach.Areasonably
good tree will produce 3050pounds of nuts at 10years age and gradually increase for
many years. If mechanically harvesting, attention needs to be paid to the efficiency of
harvesting machinery and the evenness of the soil surface. Harvest containers and
machinery equipmentmust be cleaned before use otherwise it mayincrease the risk of
contamination of the nuts and also risk of spreading diseases.
11. YIELD
Orchards in New Zealand have returned yields of 46 tonnes per hectare (http://
www.macadamia.co.nz/growingmacadamias). In optimum conditions an 8 year old tree
canproduce8kgofnutinshell(NIS).Thelargestproducerofmacadamianutsworldwide
isAustralia with40%of total worldproduction.The United States isthesecondlargest
producer followed by SouthAfrica, Guatemala, Brazil and Costa Rica. In the United
States, Hawaii dominates production with 95% of domestic macadamia nut production.
Treeage 5 6 7 8 11 25
Treeyield(Kg/tree) 2 5 8 10 1 5 55
(Source:http://www.macnut.co.nz/macadamiainfo/macadamianutgrowersguidemacnutfarms)
602MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
12.POSTHARVESTMANAGEMENT
12.1. Dehusking
Dehusking the macadamia nuts must be done within 24 hours of harvest, after which
followed by the drying process. Freshly fallen nuts contain about 25 per cent kernel
moisture,althoughnutsthat haveremainedonthegroundfor extendedperiodsmayhave
as little as 10 to 15 per cent moisture.
12.2. Drying
Theobjectofdryingismainlytoproducenutsfirm, crisp, lightin colourand freefrom
blemishes. Drying should begin with ambient air, followed by a gradual increase in
temperaturethatwillnotexceed600
Catthe finalstageofdrying.Themoisture content
ofkernelmustbereducedto1.5percentforprocessingthiscanalsobedonebyhanging
the nuts in onion sacks for 8  12 weeks depending on the ambient temperature and
humidity. It is necessary to protect the dry kernels from moisture and oxygen because
dryer the nut, higher the quality and net return.
12.3. Storage
The hard, unshelled nuts have protection against insects during storage whereas the
kernelsofshellednutsare susceptibleto infestation. So it wouldbebettertostore them
unshelled. The shelled nuts must be kept in cold storage because they are susceptible to
insect damage.They canthenimmediatelybe placedin a coldstore at 0 to 4 °C. Cold
storage prevents fungal growth and rancidity. This method is also recommended for the
longtermstorageofunshellednuts.Coldstorageisnormallynotnecessaryforshortterm
storagebut mightbedesirableforextendedperiods.Frozenstorage(18°C)canbevery
effective in extending shelflife.
12.4.Packaging
The nuts should be packed into cartons as soon as possible after shelling. Packaging is
donemainlytoavoidexposuretolight,moistureandoxygenwhichenhancesorincrease
the final taste of the nuts, and also increases theshelf life.
12.5.Grades,Sizes,andPackaging
InU.S.therearenogradesaremadeformacadamianuts,butHawaiistatehasstandards
andgradesforshelledmacadamianuts,inshellmacadamianuts,and roastedmacadamia
nuts (Hawaii Department ofAgriculture 1984). The standards grade consists of eight
styles:
MACADAMIANUT603
StyleI  Wholes
Style II  Wholes and halves
Style III  Cocktail
Style IV  Halves and pieces
Style V  Large diced
Style VI  Chips
Style VII  Bits,dice
Style VIII  Fines
Forthewholesalemarketshellednutsaremainlypackedin11.4to22.7kg(25to50
lb) vacuumpacked or nitrogenflushed foil bags but sometimes larger nitrogen flushed
containers are used.
13.VALUEADDITION
Thekernelisthemainproductfromthemacadamianuttree.Macadamia nutkernelsare
mainly used in confectionaries including chocolate bar, chocolate covered candy, ice
cream and other baking products. Macadamia nut kernel are also used for making
macadamia butter and also used in the form of roasted/fried kernel and snacks. The oil
produced by macadamia nuts can be used for cooking and in the long term could be
processedforbeautyproducts.Incosmeticsindustry,oilofthekernelisusedinshampoos,
sunscreens, soaps and others.  The shell and husk also have uses. Shells can be used as
mulch,fuelforprocessingmacadamianutsandplantingmedium.Husksareusedasfuel,
fertilizer(aftercomposting)andmulchwhereastheremainingpresscake canbe usedfor
animal feed.
14.TRADE ANDMARKETING
Thedomesticmarketconsumesabout35%oftotal production,90%ofwhich issoldas
kernel.Thepromotionofhealthbenefitsisasupportdriverofdemandand,combinedwith
new market penetration, is expected to underpin furtherindustry growth. In 2013 kernel
exports were spread relatively evenly between the USA, Japan, Europe and other Asian
markets. Asian markets are showing the greatest growth driven by increasing trade
interest and consumer awareness. In the last few years market development campaigns
have supported the product in Taiwan and Korea. On the basis of Geographical region,
globalmarketofmacadamianutisliesinNorthAmerica,LatinAmerica,WesternEurope,
Eastern Europe,Asia Pacific excluding Japan and Middle East andAfrica (Table 4). In
present North America and Western Europe had higher market share for macadamia.
Theglobalmacadamiamarketonthebasisofapplicationis broadlysegmentedintofood
industry,andcosmeticsindustry.
604MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
Table4:GlobalMacadamiaMarketRegionsandcountriesbelongingtomacadamianut
S.N. GlobalMacadamiaMarketRegions Countries
1 NorthAmerica USandCanada
2 LatinAmerica BrazilandArgentina
3 W esternEurope EU5,Nordicsan dBenelux
4 AsiaPacific Aust raliaand New Z ealan d (A NZ ), G re ate r
China,India,andASEAN
5 MiddleEastandAfrica GCCCountries,OtherMiddleEast,NorthAfrica
andSouthAfrica
(Source:QuantecEasydata)
Exportsofmacadamianutstovariousregionsoftheworldfrom2007to2011
Inpresentcompaniesareinvestingthroughpromotionalactivitiesin ordertoincrease
the footprint of macadamia worldwide. So there is a high potential to increase share of
marketof macadamiaintermsof revenue incountries likeMexico,China, SouthAfrica
and others. The key element in global macadamia marketare Mauna Loa Macadamia
Nut Corp., Hamakua Macadamia Nut Company, Wondaree Macadamias, MacFarms,
NAMBUCCA MACNUTS Pty Ltd, Golden Macadamias, Kenya Nut Company Ltd.,
Royal Macadamia (Pty) Ltd. and MWT Foods Australia.
15.EFFECTOFCLIMATECHANGEONMACADAMIANUT
In 21
st century, climate change is the greatest concern in macadamia as well as in
horticulturecrops.Changeinclimateresultsindevelopmentofthephysiologicaldisorder,
attackofpest andseriousdisease. Theeffectofchangeinclimateareglobalwarming,
MACADAMIANUT605
drought, excessiverain,meltingofice,changeofseasonalpattern,flood,rising sealevel
etc.leadingtodecreaseinyieldpotential.Theairtemperaturefor growingofmacadamia
nutvariesfrom20to25°Cwhile30°Cistheupperthresholdforproductivity.Prolonged
high temperature in macadamia nut results into leaf damage, bud damage and dieback
whereas; if low temperature doesn’t met as the requirement floral initiation is affected.
Duringdroughtfloweringresults intoreducedwater potentialin racemescauses damage
toperianths,affectingpollinationwhileduringlaterstagesofnutmaturationitresultsinto
nut drop and less percent of kernel development. Climatic conditions are also having
stronginfluenceonoilaccumulationandthesubsequentimpactofhuskspotonpremature
abscission.
16.FUTURE RESEARCHPLAN
To increaseproductivityand qualitynuts.
To make available planting material commercially.
Reduce the crop lossesdue toimmature nuts and moldy / rotten nuts
To solve the problem of inadequate valueaddition and processing.
To develop the variety resistant to biotic and abiotic stress.
Use of molecular techniques for germplasm characterization and marker assisted
selection should be a highpriority.
Useofbiotechnologytoolsapplicationsshouldbeprioritizedtoyield maximumpractical
benefits in the shortest possible time.
17.ORGANICCULTIVATION
Organiccultivationinmacadamianutaimtoachieveatotallyintegratedproductionwith
abalancedsoilecosystemencourageplantandanimalhealthandalsotominimizeinputs
in macadamia nut cultivation. The main form of organic fertilizer used in macadamia
growingisbroilerlitter.Thisisthemajorsourceofnitrogenfortrees.Itmustbecomposted
before use in an organic orchard. Composting will reduce the levels of food pathogens
toacceptablelevelsanddestroy antibioticresidues.Beforestartingorganiccultivation of
macadamianut,thosevarietyorcultivarmustbeselectedwhichareresistanttobioticand
abiotic stress. Mowing must be undertaken down and across the rows, especially when
treesareyoung.Thisisduetostrongandvigorousgrassgrowth,whichrequiresmowing
inbothdirectionsforcontrol.Whengrowingmacadamiasorganicallytheuseoftrapcrops
(example(for sting bug trap crop used are triticale, vetches and crimson clover) is also
anoptionwhichresultsinmonitoringcropofplantsthataremoresusceptibletoinsects,
and which lures the pests away from the macadamia crop.
606MINORFRUITS:NUTRACEUTICALIMPORTANCEANDCULTIVATION
References
Anonymous, 2012. Chindikani Kaseka Nyirenda,(20 12). Ma cadamia in Malawi its pest
anddiseases.http://chindikanikaseka.blogspot.in/2012/01/macadamiainmalawiitspest
and. html? view= magazine. (Jan24).
Anonymous, 2013. Reducing erosion and other soil degradationin macadamia orchards
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Chindikani Kaseka Nyirenda Macadamia in Malawi its pest and diseases
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Anonymous, 2012. Chindikani Kaseka Nyirenda,(2012). Macadamia in Malawi its pest and diseases. http://chindikanikaseka.blogspot.in/2012/01/macadamia­in­malawi­its­pest and. html? view= magazine. (Jan­24).