Botany for Master Gardeners

Kim ConwayTexas AgriLife Extension

Naming Plants

Carl Linneaus (1707-1778)

Binomial nomenclature

Based on flower parts– Family– Genus– Species

Plant Categories

Angiosperms– Monocots– Dicots

Gymnosperms– Conifers

Life Cycles

AnnualsBiennialsPerennials

– herbaceous– woody

Plant Parts & Functions

Sexual– flower

Asexual– leaves– stems– roots

Roots

Primary RootsTaprootLateral RootsFibrous

Roots

KneesButtressed

Aerial

Tuberous Roots

No Nodes

Root Structure

endodermisepidermis

phloem

root hair

pericycle

endodermis

casparian strip

meristem

rootcap

Dic

ot

Root

Dic

ot

Root

Mon

oco

t R

oot

Mon

oco

t R

oot

Stems

SupportVascular SystemBuds

– Leaf Bud– Flower Bud– Terminal– Lateral/Axillary– Adventitious

Leaves

Meristems

Primary Growth – apical meristem or apex

Secondary Growth– Vascular cambium or cambium

Primary Growth - Monocot

epidermis

vascular bundle

phloem

xylem

bundle sheath

Mon

oco

t S

tem

Mon

oco

t S

tem

Primary Growth – dicot or gymnosperm

epidermis

phloem

xylem

pith

cortex

Dic

ot

Ste

mD

icot

Ste

m

Secondary Growth - dicots

periderm

phloem

cambium

xylem

ray

crushed cortex and past year’s phloem

32 1 pith

Modified Stems - Crowns & Stolons

Modified Stems - Spurs

Modified Stems

Bulb

Tuber

Rhizome

Bulb

Corm

Types of Leaves

Scale leavesSeed leavesSpinesThornsTendrilsBrachtsNeedlesSimple

Leaves

Absorb

sunlight

for photosynthesis

Leaf LayersLeaf Layers

Stomates

Leaf Venation

PinnatePinnatePalmatePalmateParallelParallel

Double Pinnate CompoundDouble Pinnate CompoundPalmate CompoundPalmate CompoundSimpleSimpleLeaf TypesLeaf Types

Pinnate CompoundPinnate Compound

Leaf Shapes

Linear

Elliptical

Ovate

Lanceolate

Cordate

Leaf

Typ

es

Leaf

Typ

es

Leaf Margins

EntireSinuateCrenateDentateSerrate IncisedLobedCleft

Leave Arrangement

alternate oppositewhorled

whorled

Sexual Plant Parts & Functions

(Flowers)

Parts of the Flower

Petal

Anther

Filament

Sepal

OvuleReceptacle

StigmaStyle

Ovary }Stamen{Pistil

Types of Flowering Plants

Monoecious = 1 House– Corn– Pecan

Dioecious = 2 Houses– Holly– Junipers

Flowers

Complete = Pistil, Stamen, Petal, Sepals

Incomplete = Missing One Perfect = Pistil & Stamen

How Seeds Form

PollinationPollen tubeFertilization

Pollen Germination

Growth of Pollen Tube toward Ovule

Types of Flowers

Solitary - one flower per stemInflorescence - a cluster of flowers

– racemous - indeterminate (flower from the bottom up)

Racemous Flowers

Spike - flowers attached to peduncle - gladiolus

Racemous Flowers

Raceme - individual flowers attached by tiny stems to the peduncle– Bluebonnet

Racemous Flowers

Catkin – Mulberry– birch

Racemous Flowers

Corymb – yarrow

Racemous Flowers

Umbel – – dill, – onion– queen

anne’s lace

Racemous Flowers

Head –– sunflower – daisy

Flower Types

cyme - determinate - flower from the top down - top florets open first– dischasium cyme - baby’s breath– helicoid cyme - freesia– scorpioid - tomato (alternate)

Types of Inflorescence

Fruit

Fruit consists of the fertilized and mature ovules (seeds) and the ovary wall.

Parts of the Fruit

seed

dry fruit(corn) fleshy fruit (peach)

exocarp

mesocarp

endocarp

pericarp

Types of Fruit

Berry

Pepo

Pome

Hesperidium

drupe

pod

aggregate

multiple

Parts of the Seed

testa (seed coat)

hilum

micropyle

dicot seed (bean)

plumule

epicotyl

cotyledon

hypocotyl

radicle

embryo

Seed Germination

WaterLightHeatOxygen

The End