PLS 006V Module 1

Flowers in society

• Flowers have always represented a way to add

beauty and interest to our world

• Gardens represented a major form of entertainment

for the wealthy

The flowering plant industry

• Larger than most other agricultural commodities

Horticulture

Note: horticulture is part of agriculture

• all sorts of protected cultivation including gardens, vegetable

production

• Wherever man has to impose a lot of activities on the plants to

make them grow the way we want. (pinch them, etc)

• Protect the plant from (excess tempt, water, ppl stealing it, or bugs eating it)

Floriculture

the production and use of ornamental plants. It includes:

• Cut flowers

• Bedding plants (garden and landscape plants)

• Container-grown landscape plants (nursery products)

• Flowering potted plants and foliage potted plants (florist products)

• Greenhouse and nursery production (efficiency, water use, etc.)

• Postharvest handling (making flowers last longer)

• Using flowers (arrangements, decoration, etc.)

Amorphophallus titanum

a.k.a."Titan Arum" or "corpse flower"

▪ Very large flower (60 inches tall)

▪ We have some here on campus; this image

is from a few years ago.

▪ Note that central part is a stalk with

thousands of tiny flowers

▪ The flower as a whole stinks!

Flower Structure (generic flower)

Sepals

Located at base of flower; surround and protect the bud.

Flower Structure (generic flower)

Petals

Located above sepals; frequently brightly colored (attracts pollinators).

Flower Structure (generic flower)

Receptacle

Holds it all together

Flower Structure (generic flower)

Pedicel

The stem that supports a single flower in a flower cluster.

Flower Structure (generic flower)

Stamens

• Male reproductive structures

• Attached above petals

• Each consists of a:

• Filament (stalk)

• Anther (produces pollen)

Flower Structure (generic flower)

Carpel (Pistil)

• Female reproductive structure - centrally located

• Each consists of a:

• Stigma (catches pollen)

• Style - tube

• Ovary – contains one or more ovules

• Ovules develop into seeds

• Ovary develops into a fruit

Which are parts of a stamen?

a. Stigma and style

b. Petals and sepals

c. Anther and filament

d. Leaf and stem

c. Anther and filament

Which are parts of a Carpel?

a. Stigma and style

b. Petals and sepals

c. Anther and filament

d. Leaf and stem

a. Stigma and style

Which statement is correct?

a. A carpel can consist of multiple pistils

b. A pistil can consist of multiple carpels

b. A pistil can consist of multiple carpels

Perfect

• Flower that contain both stamens and pistils

• Both male and female parts in the same flower

Imperfect

• Individual flower is either male or female

• Monoecious

• Dioecious

Monoecious

male and female flowers appear on the same plant (eg. Squash)

Dioecious

a specimen of the plant is either male or female (eg Ginko trees)

Complete

Has sepals, petals, stamens, and carpels (pistils)

Incomplete

• Lacks one or more of the above structures

• All “imperfect” flowers are “incomplete”

Flower

• Dictionary non-technical: “the blossom of a plant”

• Dictionary technical: “the part of a seed plant comprising the reproductive organs

and their envelopes if any, especially when such envelopes are more or less

conspicuous in form and color”.

Blossom

• not a technical term

• Dictionary: “the flower of a plant”

Inflorescence

• Dictionary technical: the arrangement of flowers on the axis, or the flowering part of a plant, or a flower cluster or a group of flowers collectively.

Simple

One single flower per stalk

“Compound” and “Composite”

Means more than one flower grouped together

Compound

inflorescence looks like many flowers

Composite

inflorescence looks like one blossom/flower

Compound flowers – various forms:

Raceme

Unbranched, indeterminate inflorescence with pedicellate (short floral stalks) flowers along the axis

Compound flowers – various forms:

Spike

Type of raceme that do not have a pedicel

Compound flowers – various forms:

Corymb

Unbranched, indeterminate inflorescence that is flat topped or convex

Compound flower examples:

Composite flowers

▪ Multiple “florets” per receptacle

▪ Asteraceae family :

▪ Daisy family

▪ Sunflowers

▪ Chrysanthemums

▪ Dandelions

Flower Symmetry

Bilateral (Zygomorphic)

Divided by only a single plane into two mirror-image halves

Flower Symmetry

Radial (Actinomorphic)

Capable of being divided into equal halves along any diameter