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ANGIOSPERMS
Angiosperms
•Flowering plants,producingseedsthatarefullyenclosedbyfruits.
•Theyarethemosthighlyevolvedofplants,andappearfirstinrocksof
LowerCretaceousage(about130millionsyearsago).
•AllofthemareincludedinthedivisionofAnthophyta (Magnoliophyta),
comprisingabout250000species,fromverysmall(e.g.Lemna)tohuge
ones(e.g.Eucalyptus).
•Antophytaisdividedintwomainclasses:Monocotyledones (Liliopsida)
withabout65.000speciesandDicotyledones (Magnoliopsida)withabout
165.000species.
•Theirgreatimportancederivesfromthequantity,varietyandactivityof
activecompounds(secondarymetabolites)thatisthereasonofthe
phytopharmaceuticalstudy.Themajorityofmedicinalplantsare
angiospermdicotyledones.
Angiosperms
•Theyaretheplantscapabletoadapttoall
theenvironmentsandtowinthecompetition
withotherplantorganismsthanksto:
vflower
vfruit
Magnoliophyta
Eucalyptus
Lemna
Evolutionarytrendsfromgymnospermsto
angiosperms
•Slow-growingtreespecies(gymnosperms)are
displacedbyfast-growingherbs(mostevolved
angiosperms)capabletoincreaserapidlytheir
populations.
•Thelossof‘woodiness’,infavorof‘herb-ness’,
correspondstotheabandonofthemechanical
defenses againstherbivoresandpathogensin
favorofmoreselectiveandeffectivechemical
defenses,basedontheproductionofactive
compounds.
Trachea,typicalof
angiosperms
Tracheid,typical
ofgymnosperms
Fromgymnospermstoangiosperms
•Improvement of vascular tissues (appearing of
tracheae or vessels) played an important role in the
diffusion of angiosperms since it allowed an
improvement of photosynthetic activity, a higher
production of organic compounds and a faster growth.
Whyangiospermsarethemost
evolvedplants?
ØHigh rate of pollination and cross-fertilization assured by
insects and animal pollinators that are attracted to flowers.
ØPresence of a food-storing endosperm in the seed allowing to
survive under adverse environmental conditions.
ØHigh rate of seed dispersion assured by the fruit.
ØEfficient vascular system owing to the presence of tracheae
into xylem and of sieve tubes into phloem.
ØLeaf apparatus more developed and efficient for
photosynthesis.
ØDeciduous habitus allows to survive during adverse
conditions.
ØProduction of a huge amount of secondary metabolites
efficient in the defense and propagation of the plant species.
MonocotyledonesvsDicotyledones
Liliopsida
atactostele
Magnoliopsida
eustele
Tetrarchrootofa
dycotyledone
Polyarchrootofa
monocotyledone
dicotyledones
monocotyledones
Stomatadistribution
Cuscuta
Monotropa
•Almostallangiospermsareautotrophous,butthereareafewparasites
(livingonotherplantstowhichtheycancauseseriousdamage)or
saprophytes(absorbingsolubleorganicnutrientsfromdeadplant,animal
matter,dung,etc.).
Asteridae
Rosidae
Dicotyledones
Magnolidae
Monocotyledones
Protoangiospermae
Classificationaccording
toCronquist(1981)
Gnetales
Gimnospermae
Magnoliopsida(dicotyledones)
•
•
•
•
Seedwith2embryoleaves(orcotyledons).
Woodyorherbaceousplants.
Presenceofataproot.
Eustelicprimarythickeningofstem,withopened,
collateralbundles.
• Heteroxilwoodwithtracheidsandtracheae.
• Flowerwithcalyxandcorollaandwhorlsof4-5elements.
Evolutionarytrendsinangiosperms
•Indicotyledones thereisanabandonofslow-growingandelderly
treespecies(derivedfromGymnosperms)infavouroffast-growing
andshort-livingherbs,capableofproducingagreatnumberof
individualsinapopulations.
•Monocotyledonegroupsseemtobeindipendenteachother(e.g.
Orchidaceaewithcomplexandshowyflowers,Graminaewith
modestflowers,Palmaewitharboreoushabitus,Liliaceaewitha
greatvarietyofherbaceousformsetc.).
Magnolidae
• TransitiongroupfromGymnospermsatthestartof
Angiospermsevolution.
• Woodyplantswidespreadintheoldestforests(e.g.
Amazon).
• Initialprevalenceoftracheids.
• Flowerswithoutpetalsorwithmanypetalsusually
spiral-inserted.
• Atphytochemicallevel,theyproduceaminoacids
derivativessuchasalkaloidsandphenoliccompounds
derivedfromshikimicacid(e.g.simplephenols,
gallotannins).
• Theyincludeabout20familiesamongwhich
Magnoliaceae,Lauraceae,Piperaceae,
Aristolochiaceae,Nympaeaceae etc.
Rosidae
• Theyabandonthewoodyhabitusinfavourof
shrub/herbaceoushabitus.
• Flowermorecomplex:2groupsofspecializedfloral
leaves(regular,actinomorphicflowersradially
symmetrical;calyxwithsepalsandcorollawith5
separate,showyandmorphologicallysimilarpetals).
• Zygomorphicflowers(i.e.bilaterallysymmetricaland
thereforedivisibleintoequalhalvesinonly1plane)in
themostevolutedforms.
• Phenylpropanidunits,previouslyusedforthesynthesis
oflignins,arenowusedtoproducecoumarins,tannins
andflavonoids.Atthebeginning,theproductionof
terpenoids,whilelittlethatofalkaloids.
Asteridae
• Maximumistheherbaceouscharacterandshortthelife
cycle.
• Flowershapereachesthegreatestcomplexityasa
consequenceofthemaximumspecializationtowards
pollinators.Zygomorphicflowerwithtube-shapedcorolla,
orarrangementofmoreflowersinparticularinflorescences.
• Becauseoftheirwidesecondarymetabolism,theyhave
colonizedmostoftheplanetandconstitutedanimportant
sourceofactivecompoundstobeusedintherapy.The
secondarymetabolitesarerepresentedmainlyby
terpenoidsthatinthearomaticplantsreachtheirmaximum
expression.
Liliopsida(monocotyledones)
• Seedwithonecotyledon.
• Habitusonlyherbaceous.Lackingofthesecondary
thickening(exceptPalmae).
• Fibrousroots;presenceofadventitiousrootsonthestem.
• Atactostelestructureofstem,withclosedvascularbundles
randomlydistributed.
• Simple,sessileleaves,withamplexicaulsheathandparallel
nervation.
• Flowerscomposedof3elements;nodistinctionbetween
calyxandcorolla:sepalsandpetalsaredisplacedbytepals.
• Unlikedicotyledones,thevariousgroupsaretaxonomically
indipendent.
• Secondarymetabolitesvariedbetweenthevariousplant
groups.Anyway,theyarenotsonumerousasinthemost
evolvedformsofdicotyledones.
Angiospermsaretherichest
sourceofactivecompounds
•Thenumberofpharmacologically-activecompounds
(drugs)increasesfromwaterorganisms(e.g.Algae)to
terrestrialplants,aswellasfromphotosynthetically
inefficientBryiophytestothoseefficient(e.g.broad-leaf
Angiosperms).
•Asamatteroffact,thehigherenergyderivedfrom
photosynthesisandthebetterphysiologicalefficiency,
stimulatedthesyntheticpotentialofplantssothatthey
interactwiththeenvironmentthroughtheproductionofa
greatnumberofsecondarymetabolites.
ClassificationaccordingtoCronquist(1981)
Magnolidae
•Monimiaceae
•Lauraceae
•Illiciacee
•Papaveraceae
Rosidae
•Rosaceae
•Mimosaceae
•Fabaceae
•Caesalpiniaceae
•Myrtaceae
•Euphorbiaceae
•Rhamnaceae
•Hippocastanaceae
•Rutaceae
•Araliaceae
Monocotyledones(Liliopsida)
•Apiaceae
•Liliaceae
•Poaceae
•Zingiberaceae
•Iridaceae
•Aloeaceae
Asteridae
•Gentianaceae
•Apocynaceae
•Solanaceae
•Lamiaceae
•Plantaginaceae
•Scrophulariaceae
•Rubiaceae
•Valerianaceae
•Asteraceae
Flower
•Floweristhestructureconcernedwithsexualreproduction,
consistingoftheandroecium (maleorgans:stamens)and
gynoecium (femaleorgans:carpels),commonlysurroundedby
sterilecorolla (petals)andcalyx (sepals).
Flowerandreproduction
•Floweriscomposedof4groupsofmodifiedleaves:sepals,petals,stamens
andcarpels.
•Sepals aretheouterfloralleaves,usuallygreenish,whichareborneinatight
spiralorwhorled.Theyformcalyx whichprotectsflower(formingbuds)before
opening.Sepalscanbeseparateorfused.Sometimescalyxispersistentand
accompaniesfruitafterfertilization.
•Petals aretheinnerfloralleaves,usuallybrightlycolouredorsmellingto
attractpollinators,andborneinatightspiral,orwhorled.Theyformcorolla
whichenclosesthereproductiveorgansand,togethercalyx,protectsthem.
Petalscanbeseparateorfused.Afterfertilizationpetalsfalldown.
•Stamens arefertileleaves(sporophylls)formingthemaleorganscomprising
astalk(thefilament)andtheanthers whicharecommonly2-lobed.Anthers
containmicrosporangia thatproducemicrospores givingrisetomale
gametophytes.
•Carpels arefertileleaves(sporophylls)formingthefemaleorganscomprising
anovary (containing1tomanyovules borneonaplacenta)andwithausually
terminalstyle tippedbythestigma.Ovulescontainmegasporangia that
producemegaspores givingrisetofemale gametophytes(embryosac).
Structureofflowers
PERFECTorMONOCLINOUS
(BISEXUAL)
IMPERFECTorDICLINOUS
(UNISEXUAL)
Stamensandcarpelsoccurin
thesameflower
Stamensorcarpelsinseparate
flowersinthesameplant
MONOICIOUSPLANT
DIOICIOUSPLANT
Plant with bisexual flowers, or
alternatively with both stamen and
carpels in flowers in the same individuals
Flowers with stamens and
carpels in separate individuals
COMPLETE
INCOMPLETE
Withsepals,petals,stamensand
carpelsinthesameflower
Lackofoneormorefloralparts
Floralsymmetry
Regularflowers
(Actinomorphic)
Irregularflowers
(Zygomorphic)
Similar elements ofwhorls,with
radial symmetry,i.e.divisible into
equal halves inmany planes
Differentelementofwhorls,with
bilateralsymmetry,i.e.divisibleinto
equalhalvesinonly1plane
Morphologyof
calyxandcorolla
Morphologyof
calyxandcorolla
Originofthecarpelfromareproductiveleaf
(sporophyll)
•Aleafbearingmegasporangiafoldedinordertoprotectthem.
Inflorescences
Monopodialorindefinite
(lateralfloralbranchesarisefrom
amain,centralaxis)
•Racemeorcluster
•Spike(spadix,catkin)
•Corymb
•Umbel
•Capitulum
Sympodialordefiniteor
cymose
(apparentmainaxismadeupof
manylateralfloralbranches,
eacharisingfromtheonebefore)
•Monochasium
•Dichasium
Compound(mainaxiswithlateralbranchesbearing
thesameoradifferenttypeofinflorescence)
•Panicleorcompoundraceme
•Compoundumbel
•Polychasium
•Spikeletorcompoundspike
•Clusterofcapitula
•Clusterofspikes
Inflorescences
panicle
composite umbel
spike
raceme
corymb
helicoid
monochasium
dichasium
scorpioid
monochasium
spadix
umbel
capitulum
polychasium
•Monopodial orindefinite
inflorescences
•Compound anddefiniteinflorescences
Monopodial inflorescences
•Raceme:themainaxiscontinuestogrow,producingflowerslaterally
withpedicels.
•Spike:aracemeinwhichtheflowersareallsessile;ischaracteristicof
Poaceae.
•Corymb:aracemoseinflorescenceinwhichthelowerpedicelsare
longerthantheuppersothattheflowerslieasadome,ordish,and
theoutlineisroundishorflattish.
•Umbel:allthepedicelsariseattheapexofanaxis.Itiscommonly
compound,usuallyumbrella-shaped,andischaracteristicofApiaceae.
•Capitulum:consistsofcloselypackedflowersorfloretswhichhaveno
stalksandariseonaflattenedaxis,allatthesamelevel.Itis
surroundedbyaninvolucreofbractsgivingittheappearanceofa
singleflower.CapitulaaretypicalofAsteraceae.
Cymose andcompound
inflorescences
•Monochasium:consists ofasinglefloral branch bearing flowers andending
inasingleterminalflower (e.g.scorpioid andhelicoid cymes).
•Dichasium:each branch give risetotwo morebranches.
•Polychasium :each branch give risetomany morebranches.
•Panicle:acompoundraceme,i.e.one that comprises several racemoseparts;
it is characteristic ofPoaceae.
•Compoundumbel:anumbel inwhich thepedicels give risetoother umbels;
it is typical ofApiaceae.
•Spikelet orcompoundspike:aspike inwhich shortbranches give riseto2-3
spikes;it is characteristic ofPoaceae.
•Clusterofcapitula:aracemoseinflorescence inwhich thepedicels give rise
tomany capitula.
•Clusterofspikes:aracemoseinflorescence inwhich thepedicels give riseto
many spikes.
Inflorescences
Inflorescences
Inflorescences
•Capitulum:consistsofcloselypacked
flowersorflorets(discandrayflorets)
whichhavenostalksandariseona
flattenedaxis,allatthesamelevel.Itis
surroundedbyaninvolucreofbracts
givingittheappearanceofasingleflower.
CapitulaaretypicalofAsteraceae.
Inflorescences
Capitulum of thistle with
only tubular, disc florets
Capitulum
of
dandelion
with
only ligulate, ray
florets
Capitulum
of
sunflower
with
both tubular and
ligulate florets
Inflorescences
•Compound umbel:all thepedicels arise attheapex ofan
axis;each pedicel gives riseto one umbel.It is characteristic of
Apiaceae.
Inflorescences
simpleumbel
compoundumbel
Inflorescences
•SpikeletistypicalofPoaceae.
Inflorescences
•PaniclesofZeamays
Development
of
gametophytes
sporogenesis
gametogenesis
Stamens
•Stamenisthemaleorganofa
flower,comprisingastalk(the
filament)andtheanther whichis
commonly2-lobed,eachlobe
containing2pollensacs
(microsporangia) inwhich
microsporocytes undergo2meiotic
divisionstoproduce4microspores
thatbecomepollengrains.
immaturepollengrain
Pollengrain
•Pollengrainderivesfromgerminatingmicrospore.Itcontainsthe
malegametophyte,astructuremadeupofthepollengrainplusa
pollentube.Thegraincontains3haploid nuclei(atubenucleusand2
spermnuclei).
Pollengrain
• Pollengrain(20-250μm)isprotectedby
anouterenvelopecalledexin (composed
ofsporopollenin)showingvarioustypes
ofsculptures(taxonomicvalue),andbyan
innerenvelopecalledintin (composedof
celluloseandpectins).Itbearsstretched
orcircularopeningsfromwhichthepollen
tubecomesout.Theyareknownassolcus
andporus.
• Pollengrainsareanimportantsourceof
nutrientsforanimalsandinsects(richof
starchandlipids).
• Theyarefrequentinfossils.
VariouskindsofpollengrainsatSEM
Carpel
•Carpel isthefemalereproductiveorgan
oftheflower,i.e.aunitofthegynoecium,
comprisinganovary (containing1tomany
ovules borneonaplacenta)andwitha
usuallyterminalstyle tippedbythe
stigma.
•Styleisanextensionofthecarpelwhich
supports thestigma.
•Stigmaisthepartonwhichpollengrains
germinate.
c
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l
Pollinationandpollen
tubeformation
•Stigma isthepartonwhich
pollengrainsgerminatethrough
absorptionofwaterand
consequentformationofthe
pollentube.
•Angiospermshaveastigmatic
pollination.
Pollinationandpollen
tubeformation
•Thepollen grain contains 3haploid nuclei
(atubenucleus and2 sperm nuclei),which
passdownthetube to theovum.One of
thesperm nucleifertilizes theovum,and
thesecond fuses with the2polar nuclei
forming theendosperm.Thetubenucleus
(which is considered to be vestigial,having
been completely functional earlier inthe
evolution offlowering plants)degenerates
after double fertilization (socalled because
ofthetwo unions ofnuclei).
•With the appearance of flower,
angiosperms have solved the
problem
related
to
the
impossibility to move towards a
reproductive partner.
•Flower assures a high rate of
cross pollination.
•Pollination is thetransferofpollen grains (containing male
gametophytes)fromtheanther tothestigmaofaflowering
plant.Flowers andinsects have co-evolved.
•Inabattle ofthree armies,Large
Bluesbutterflies arelured to
oregano plants where theinsect
flyers lay their eggs.After two
weeks,theconsequent
caterpillarscrwal tothebottom
oftheplant where they exude a
scent that tricks Myrmica ants
into carrying thebutterfly larvae
into theundergroundcolony.The
caterpillarsspend thenext 11
months feeding ontheant grubs
andgaining 98%oftheir body
mass,before ultimately killing the
colony andescaping.
•Rosemary’santhersdepositingwhitepollen
grainsonhairybackofabee.
•Flowerspollinatedbybeesareyelloworbluesince
theseinsectsarenotsensitivetoredwavelenghts.
•FlowerofDigitalis withtubular
corollashowinginsidesomestains
actingaslandingplatformforbees.
•FlowersofthegenusOphrys
(Orchidaceae),mimingtheshape
ofafemalebee,attractmale
pollinators.
•Nectarsareanimportantfeedingsourcefor
pollinators.Theyaresecretorystructures
producingenergeticnutrients.
•Flowerspollinatedbybirdsareoftenofredcolour.
•Graminaehaveananemophilous
pollination:hairystigmasgetpollen
grainsfromhanginganthers.
•Wind-pollinatedplantsdonot
dependoninsectssothattheydonot
spendenergyfornectarproduction,
andarecolourlessandodourless.
•Anemophilouspollinationisless
efficientandsucceedsonlywhena
highnumberofindividualsofa
populationstaycloseeachother(no
fartherthan100m).
•Someaquaticangiospermsarepollinatedbywater.
•Themostimportantpigmentsforthecolour
offlowersareflavonoids (mainly
anthocyanins)andcarotenoids.
•Fertilizationinvolvesthefusionoftwohaploidnucleifromtwo
distinctindividuals(cross-fertilization)orfromoneindividual(selffertilization).
•Normallymaleandfemaleorgansofaflowermatureatdifferent
times(dichogamy),oralternativelytheyarephysicallyseparatedin
ordertofavourcross-fertilization.
•Plantswithself-pollination havesmall,colourlessflowers
sincetheydonotneedtoattractpollinators.
•Self-pollinatedpopulationshavealowlevelofgenetic
variability.
•Self-pollinationisfavouredinsomecases(e.g.disturbed
areaswherepollinatorsarerare).
Femalegametophyteanddoublefertilization
•Thefemalegametophyte,knownasembryosac,is
anovalstructureinthenucellus oftheovule of
floweringplants,formedbythedivisionofthe
haploidmegaspore nucleus(whichisproducedby
theonlydiploidcellundergoingmeiosisinthe
megasporangium),andthesiteoffertilization ofthe
egganddevelopmentoftheembryo.
•Itconsistsof6haploidcellswithoutcellwalls(2
synergidae,3antipodalcells,andaneggcell)and2
haploidnuclei(polarnuclei).Sometimesthe2
haploid,polarnucleifusetoformasingle,
endospermmothercell.Atfertilization,1male
nucleusfuseswiththeeggnucleustoformazygote
whichdevelopsintotheembryo.The secondmale
nucleusfuseswiththeprimaryendospermnucleus
toformtheendospermnucleus.Thisthendividesto
formtheendosperm.
Doublefertilization
•It occurs only in angiosperms and is the production of 2 sperm nuclei, both
of which contribute to fertilization.
•The male gametophyte, comprising the pollen grain and pollen tube,
contains 2 sperm nuclei and 1 vegetative nucleus.
•The vegetative nucleus degenerates once the pollen tube has penetrated
the embryo sac by micropyle.
•The 2 sperm nuclei enter the embryo sac. One unites with the egg nucleus
to form the zygote, which develops into the embryo. The other unites with
both of the polar nuclei or with the nucleus formed by their fusion, to form
the primary endosperm nucleus, from which endosperm develops.
•Endosperm is a triploid tissue storing food materials which are broken
down during seed germination.
•Double fertilization assures endosperm development just in the case of egg
cell fertilization, avoiding the waste of nutritive substances.
Doublefertilization
Seed
•Seed ofangiospermsiscomposedof2
diploid generations(theouter
integuments andtheembryo)andone
triploid generation(endosperm).
•Embryohasusually1or2cotyledons.
•Endosperm functionsasstorageof
nutrients(carbohydrates,proteins,lipids)
forembryoandseedgermination.
•Seednutrientsarestoredinthevacuole
orleucoplasts ofendospermcells.
Lifecycleofanangiosperm
Fruit
• After fertilization, ovule is transformed into seed,
ovary into fruit.
• Fruits protect quiescent seeds and contribute to their
dispersal.
Fruit
• Ovarywallsknownaspericarp,
thickenanddifferentiateinto3
layers:theinnerendocarp,the
middlemesocarp andtheouter
exocarp.Theselayersareusually
moreevidentinfleshyfruits.
Classificationoffruits
origin
AGGREGATE
SIMPLE
MULTIPLE
formed by the joining of several
carpels that were separate in
the flower (e.g. Rubus).
formed from a single carpel
or from various fused carpels
formed from
inflorescence
pineapple)
dehiscence
INDEHISCENTremainingclosedat
maturity
openingnaturallyatmaturity
follicle,legume,lomentum,siliqua,
capsule,schizocarp
consistence
FLESHY(oneor
DRY(oneseed)
berry,drupe,pome
samara,nut,achene,
caryopsis
moreseeds)
DEHISCENT(many-seeded,dry)
an entire
(e.g.
fig,
Classificationoffruits
TRUE
Strictly,theripened
ovaryofaplantandits
contents
FALSE
Whentheripenedovary
andseedsarecombined
withotherstructures;e.g.
theapple(apome)inwhich
thetruefruit(core)is
surroundedbyfleshderived
fromthefloralreceptacle.
Fleshyfruits
• Drupe: a fleshy indehiscent fruit containing one or a few
seeds, each enclosed within a stony endocarp, as in the genus
Prunus (Rosaceae).
Fleshyfruits
• Berry:afleshy,indehiscent,fruitcontainingmanyseeds
immersedinapulp(endocarp+mesocarp);theydonothave
hardpartsexcepttheseeds(e.g.grape,tomatoes,blueberry,
currant,banana,avocado,pepper,eggplant,belladonna).
Fleshyfruits
• Hesperidium:aberryinwhichthefleshypartisdividedinto
segmentsandtheouterskinisatough,glandularleathery
rind,e.g.Citrus(Rutaceaesuchasorange,lemonetc.).
Fleshyfruits
• Pepper:aberry,typicalofCapsicum wherethefleshy
pericarpsurroundsahollowcontainingmanyseeds.
Fleshyfruits
• Pepo:aunilocular,many-seeded,hard-walledberrythat
formsthefruitofCucurbitaceae(e.g.marrow,melon,
watermelon,cucumberetc.).
Fleshyfruits
• Sorosis:afleshy,aggregatefruit(e.g.mulberry,currantetc.);
strawberryisanaggregate,falsefruit,wherethepulp
originatesfromreceptaclewhilethetruefruitsareachenes.
Fleshyfruits
(enlargementof
thereceptacle)
• Pome:fruitinwhichtheseedsareprotectedbyatoughcarpelwall
andtheentirefruitisembeddedinafleshyreceptacle;inthe
apple,thecarpelwallsurroundingtheseedscomprisesthecore,
whichisthefruit,theediblefleshypartoftheapplebeingthe
receptacle.
Fleshyfruits
• Syncarp:afleshy,multiplefruitformedfroman
inflorescence,oftenincludingbracts,asinpineapple.
Ripening
immature
• Ripeningisastageinthe
developmentoffruit,characterized
bythesoftening,colouring,and
sweeteningofthetissue,andbya
decreaseinacidity.Oftenthisis
associatedwithanincreaseinthe
ratesofrespiration,cellexpansion,
andethylene production,combined
withalossofchlorophyll.
• Thecolourchangeisasignalforthe
seeddispersors.
ripening
Ripening
• Redcolourisdominantamongripefruitssince
animals,thataresensitivetoredwavelenghts,are
thebestseeddispersors.
Dryfruits
• Follicle:adryfruit derived from asingle
carpel,containing morethan one seed,
which dehisces along one side (along the
suture)only.
• Siliqua:thecapsularfruit ofthe
Brassicaceae when atleast three times as
longas broad,containing many seeds
attached to acentral outgrowth known as
replum;it dehisces along dorsal andventral
sides (sutures).
Dehiscentfruits
• Capsule:adry,dehyscentfruit
formedfromasyncarpous
ovary;itcontainsmanyseeds
andopensindifferentways.
Dehiscentfruits
• Legumeor pod:atwo-valved
fruitformedfromasingle
carpel,usuallyseveralseededandusuallyopening
alongdorsalandventral
sides,typicalofFabaceae.
Dehiscentfruits
• Lomentum:afruitderived
fromasinglecarpelwhich
breaksupintoone-seeded
portions,asincarobtree
andtamarind.
Dehiscentfruits
• Schizocarp:afruitderivedfroma
syncarpousovarywhichbreaksupat
maturityintoone-seededportions
(mericarps),asinmostmembersof
Lamiaceae(4mericarps)andApiaceae
(2mericarps).
Indehiscentfruits
•Samara:adry,indehiscent,winged
1- or2-seeded(doublesamara)nut
orachene,characteristicofthe
genusFraxinus andAcer.
•Achene: a small, dry, oneseeded, indehiscent fruit,
strictly of one carpel.
Indehiscentfruits
• Cypsela:asmall,dry,one-seeded,indehiscentfruitformed
fromtwounitedcarpels,normallyaccompainedbypappus,
asintheAsteraceae.Sometimestreatedasaformofachene.
Indehiscentfruits
• Nut: adry,one-seeded,
indehiscentfruitwithawoody
pericarp(e.g.acorn,hazelnut,
walnut);theseedisnotunitedto
thepericarp.
Indehiscentfruits
• Caryopsis:adry,one-seeded,indehiscentfruit,characteristic
ofgrasses(Poaceae),havingthepericarpunitedtotheseed;
thegrainofacerealgrass.
Fruitdispersal
•Fruits of devil’s claw with hooks
joining to fur coat of animals.
Pharmaceuticalimportanceof
fruitsandseeds
•Thefollowingfruitsareusedinpharmaceutical
preparations:papaya,orangeandcitrus,anise,star
anise,capsicum,senna.
•Severalplantsprovideseedcontainingoilstobeused
inpharmaceutics:rape,linseed,cotton,castor,coconut,
sesame,etc.
•Otherseedusedinpharmaceuticsare:coffee,cocoa,
sweetandbitteralmond,walnut,hazelnut,chestnutetc.