Three types of fruit formation - horticulturebc.info Types.pdf · 1. Simple fruits Form from a single flower with one pistil 2. Aggregate fruits Form from a single flower with many

1. Simple fruits

Form from a single flower with one pistil

2. Aggregate fruits

Form from a single flower with many pistils

3. Multiple fruits

Form from many florets in an inflorescence

Fruitlets fuse together into one, bigger fleshy fruit

or they fall off the plant as a dry fruit cluster

Three types of fruit formation

Fruit may also contain accessory tissue (parts not derived from the ovary)

1. Drupe

2. Berry (true)

3. Pepo

4. Hesperidium

5. Pome

Simple Fleshy Fruit Types

Simple fruit may arise from a simple pistil (one carpel) or compound pistil (two or more

carpels).

Fruit Types © KPU.ca/Hort

1 carpel

Drupe: fruit usually with a fleshy mesocarp and a single seed enclosed in a hard stony

endocarp or pit (e.g. peach, plum, beautyberry). Exception: holly has 4 to 6 seeds each with

their own hard endocarp (called pyrenes). Fruit Types © KPU.ca/Hort

seed

endocarp mesocarp

True berry: fleshy fruit (mesocarp + endocarp) with thin skin (exocarp) and usually few to

many seeds (e.g. Vitaceae - grape).


Tomato (a true berry): pericarp (exocarp, mesocarp, endocarp), seed, locule, placenta.


Pepo: a berry with a tough skin called the rind that is derived from accessory tissue (the

floral tube) and the ovary’s exocarp (Cucurbitaceae, e.g. squash).


Parthenocarpic fruit: mature to become fleshy without the ovules ripening into seeds.


banana

long English cucumber

seedless grapes

watermelon

Hesperidium: a berry with leathery outer skin containing citrus oil; carpels evident in cross

section (Rutaceae e.g. lime).


Pome: may be berry-like but has leathery or papery endocarp and fleshy accessory tissue

derived from the floral tube (inferior ovary).


Accessory

tissue

calyx

(remains at the distil end)

Accessory

tissue

Pedicel

Locule

Seed

Pome: fruit with leathery or papery endocarps surrounded by fleshy

accessory tissue derived from the floral tube (e.g. some Rosaceae - pear, cotoneaster, etc.).


Simple dry Indehiscent fruits

1. Samara

2. Nut

3. Achene

4. Grain

5. Schizocarp

Samara (key): indehiscent dry fruit with wing(s) for wind dispersal


maple

ash

tree of heaven elm

American hop hornbeam

Nut: indehiscent dry fruit with a hard pericarp from a compound pistil but usually only one

seed develops. Exception: beech (top right) has 3-angled nuts from compound ovary

enclosed in prickly bracts that split open like a capsule. Nuts can also be very tiny, e.g. those

from alder catkins (Betulaceae), or from the persistent calyx of lavender (Lamiaceae).


walnut is

drupe-like

hazelnut

chestnut

oak

beech

lavender

alder

Achene (&/or cypsela): pericarp and seed loosely attached


sunflower

dandelion

clematis

Grain (caryopsis): fruit wall fused to the seed coat (e.g. oats, and all Poaceae species)


Schizocarpic fruit: at maturity the compound pistil splits apart into separate carpels called

mericarps that fully enclose the seed. In Apiaceae there are two mericarps. (FYI: In

Geraniaceae there are 5 mericarps each with a single seed that is forcibly discharged!)


fennel

geranium

1. Follicle

2. Legume

3. Silique/ silicle

4. Capsule

Simple dry Dehiscent fruits

Follicle: splitting along one edge only (single carpel spliting along the margin).

Usually, several form per flower to form an “aggregate of achenes”.


milkweed peony

Legume: fruit splitting along both edges (Fabaceae, e.g. honey locust, wistera, bean)


Legume (pea) parts: pericarp, seed, locule (air space round seed), placenta


Silicle: Fruit less than twice longer than wide (e.g. dollar plant)

Silique: Fruit more than twice longer than wide (Brassicaeae, e.g. stocks)

Note the central partition to which the seeds are attached (two compartments)


Capsule: fruit with a compound pistil splitting along or between carpel lines splitting at a

number of edges lengthwise. Some form a cap that comes off or a row of pores that open

near the top (e.g. poppy)


golden rain tree poppy

lily princess tree

1. Simple fruits


2. Aggregate fruits


3. Multiple fruits


Fruitlets fuse together into one, bigger fleshy fruit or they fall off the plant as

a dry fruit cluster



Aggregate fruit: fruit divided from a single flower having several to many pistils


magnolia is an

aggregate of 1

seeded follicles

tulip tree

aggregate

of samaras

blackberry

aggregate

of drupes

strawberry of

achenes (on

accessory tissue)

Rose hip: similar to pome except it contains many achenes (an aggregate fruit type with

accessory tissue)


1. Simple fruits


2. Aggregate fruits


3. Multiple fruits


Fruitlets fuse together into one, bigger fleshy

fruit or they fall off the plant as a dry fruit cluster



Multiple fruit: derived from several to many separate flowers in an inflorescence, the fruit

fuse to form a single fruit at maturity or the fruit untit drops from the plant before the seed

is dispersed (e.g.,, fig,, and) Fruit Types © KPU.ca/Hort

pineapple

Chinese

dogwood

sweet gum

corn

cob

fig

plane tree

In grape, the fruit is thin-skinned and fleshy throughout.

Unknown # 1


In rhododendron the florets form dry fruit that split lengthwise to release the seeds.

Unknown # 2


Unknown # 3

In strawberry, the fruit is derived from a single flower with many pistils (each ovary becomes an achene stuck to the outside).


The florets in golden chain tree (Fabaceae) form dry fruit that split lengthwise along two sides to release the seeds.

Unknown # 4


In hawthorn, remnants of the calyx indicates it has accessory tissue (there are several unprotected seeds inside).

Unknown # 5


In beech, each floret produces a few hard indehiscent fruit (one per pistil), that are protected by accessory tissue (whorl of bracts).

Unknown # 6


In ninebark, each floret forms 4 or 5 dry fruit: each split lengthwise on one side to release the seed.

Unknown # 7


Cornelian dogwood forms fleshy fruit with the seed in a hard pit.

Unknown # 8


The florets from this head inflorescence from strawflower form indehiscent fruit with hairs for wind dispersal.

Unknown # 9


The florets in the mulberry catkin turn into berries and fuse multiple fruit.

Unknown # 10


Answer Key

1. Berry

2. Capsule

3. Aggregate fruit (achenes)

4. Legume

5. Pome

6. Nut

7. Follicle

8. Drupe

9. Achene (or cypsela)

10. Multiple fruit


Use the KPU Plant Database to search for more fruit type examples: Morphological Search, click Expand > Fruit Type

https://plantdatabase.kpu.ca/

Documents

Three types of fruit formation - horticulturebc.info Types.pdf · 1. Simple fruits Form from a single flower with one pistil 2. Aggregate fruits Form from a single flower with many