Reproductive Anatomy - Crop and Soil Science

Reproductive Anatomy
Thomas G Chastain
CROP 200 Crop Ecology and Morphology
Reproductive Anatomy
• Flower buds are meristematic
tissues that will develop into a
flower and its parts.
• Sepals are the structures that
enclose the bud until the flower
opens near the end of floral
development.
Canola flower buds (TG Chastain photo)
Reproductive Anatomy
Reproductive Anatomy
Stamens and anthers with pistil visible in the middle of
the flower in potato (top-left), tiger lily with stamens
and pistil visible (bottom-left), red fescue florets with
stamens (above-left), and perennial ryegrass floret
with stamen (above-right).
TG Chastain photos
Reproductive Anatomy
Legume flower
Pea flower
Reproductive Anatomy
Brassica flower
Canola flower (TG Chastain photo)
Reproductive Anatomy
• An inflorescence is a group or
groups of flowers arranged
either on a single stem or on
branches.
• There are several types of
inflorescences found in crop
plants.
• A raceme is a branched
inflorescence where the
flowers are borne on short
stalks extending from a central
axis.
Canola raceme (TG Chastain photo)
Sunflower
head
Reproductive Anatomy
• Head (or capitulum) is an un-branched
inflorescence of sessile or nearly sessile
flowers on a short or flattened axis.
• Composite heads have two types of
flowers: ray flowers and disk flowers
Ray flower
Red clover
head
Disk flowers
TG Chastain photos
Top view
Reproductive Anatomy
• The umbel is a branched inflorescence.
Carrot (left) and onion (right) umbels.
Bottom view
TG Chastain photos
Reproductive Anatomy
• The panicle is a branched inflorescence, often found in the grass family.
Panicles in orchardgrass (left) and wild oats (right) TG Chastain photos
Reproductive Anatomy
• The spike is an un-branched inflorescence, often found in the grass family.
Barley spikes (left), wheat spikes (right)
TG Chastain photos
Reproductive Anatomy
Comparison of panicle and spike
Spike - a non-branched
inflorescence.
Panicle - a branched
inflorescence.
Spikelet
Rachis
TG Chastain photos
Sterile
Floret
Rachilla
Floret
Reproductive Anatomy
• A spikelet is a sub-unit of a grass
inflorescence. Each spikelet is
composed of two glumes and one to
many florets (flowers).
Floret
Glume
Glume
Pedicel
Pedicel
Expanded spikelet (left), normal condition
of spikelet (above) TG Chastain photos
Reproductive Anatomy
• The fruit is a matured ovary and
associated flower parts.
• Caryopsis – a single-seeded dry fruit
that does not split to release seed.
Seed coat is the pericarp, maternal
tissue. Example: wheat and other
grass seed.
• Legume – a multiple-seeded dry fruit
that splits to release seed. Example:
soybeans and other legumes.
Wheat and corn caryopses (top), soybean
legumes (bottom)
Reproductive Anatomy
Pea legume = Ovary
Ovule
Pericarp
TG Chastain photos
Reproductive Anatomy
• Silique – a multiple-seeded dry
fruit that splits to release seed.
Fruit is more than twice as long as
it is broad. Example: canola.
• Achene – a one-seeded dry fruit
that does not split at maturity to
release seed. Pericarp is fused to
seed inside. Example: sunflower.
Canola silique (top), sunflower achene (bottom)
TG Chastain photos