Fruit and its type

• Fertilized ovary is called fruit.
• It has two parts i.e. fruit wall or pericarp and seeds.
• Pericarp is made up of three layers epicarp, mesocarp and endocarp.
• Fruits might be true fruits and false fruits.
• True fruit develops from ovary and false fruit develop from any part other than ovary.

Types of fruits:

• Fruits are of three types.
• They are simple, aggregate and multiple or composite

1) Simple fruit:

• Develops from syncarpous ovary or monocarpellary ovary.
• It is divided into two types.
• They are dry fruits and fleshy fruits.

Image source: toppr

A) Dry fruits

• Pericarp is not differentiated into three regions.
• It is again divided into three types.

i) Dehiscent or capsular fruits.

It is of following types. They are:

a) legume or pod

• Develops from monocarpellary gynoecium.
• Dehiscence occurs by both the halves by means of suture.
• e.g., pea, gram, bean.

b) Follicle

• Develops from bicarpellary gynoecium.
• Unilocular ovary dehiscence occurs by only one halves.
• e.g., Calotropis.

c) Siliqua

• It is elongated, linear, many seeded.
• Develops from bicarpellary.
• Dehiscence occurs by both the halves from base to the apex.
• e.g., Cruciferae.
• Siliqula is a flat siliqua e.g., Iberis, Capsella.

d) Capsule

• Develops from multicarpellary syncarpous ovary.
• Dehiscence occurs by pore (poricidal) e.g., Opium and Argemone, locule (loculicidal) e.g., cotton, ladyfinger, septa (septicidal) e.g., Linum.
• Septa breaks down into segments (septifragal) e.g., Datura.

Image source: botanyworld

ii) Indehiscent or achenial fruits

• These are single seeded, indehiscent dry and simple fruits.

a) Achene

• Formed from monocarpellary pistil having superior and unilocular ovary.
• The pericarp is membranous or leathery.
• Pericarp is free from seed coat except one point.
• e.g., Mirabilis, Boerhaavia, Fagopyrum, etc.

b) Caryopsis

• Pericarp and testa are completely fused.
• e.g., maize, rice, wheat, etc.

c) Cypsela

• Developed from an inferior bicarpellary ovary.
• e.g., compositae.

d) Samara

• One or two seeded, winged fruits developing from bi or tri-carpellary ovary.
• In samara, wings develop from pericarp e.g., Hiptage, Fraxinus, Dioscorea.
• While in case of Shorea (sal) and Dipterocarpus, wings are formed by persistent sepals.

e) Nut

• One seeded fruits developed from superior, syncarpous pistil.
•  Pericarp hard and woody or leathery.
• e.g., Anacardium (cashew nut), Quercus (oak), Litchi.

Image source: brainkart

iii) Splitting or schizocarpic fruits.

• Many seeded, dry and simple fruits. which break up into one seeded parts at maturity.
• Indehiscent single seeded compartment is called mericarp while the dehiscent parts are called cocci.
• These are of following types:

a) Lomentum

• It is constricted pod.
• e.g., Acacia, Mimosa, Cassia, etc.

b) Cremocarp

• Two seeded fruit, at maturity splits into two mericarp.
• e.g., Coriander, carrot, etc.

c) Carcerulus

• Fruits are broken into indehiscent and single seeded mericarp.
• e.g., Malva, Althaea, Abutilon, etc.

d) Double samara

• Fruit develop from superior bicarpellary ovary.
• When mature it splits into two samaras (mericarp).
• e.g., Acer.

Image source: ecobiohub

e) Regma

• Dry, three to many chambered fruit developing from a syncarpous pistil.
• It splits up at maturity into cocci or dehiscent single seeded parts.
• e.g., Ricinus, Euphorbia, etc.

B) Fleshy fruits

• Pericarp is divided into three distinct regions.
• Pericarp or its associate parts become fleshy.
• These are of various types. They are:

i) Drupe

• Fleshy one or more seeded fruit.
• The pericarp differentiated into outer skin or epicarp, often fleshy or fibrous mesocarp and hard or stony endocarp.
• Fruit is also called as stone fruit.
• e.g., mango, coconut, plum, almond, etc.

ii) Bacca or berry

• Fleshy superior, usually many seeded fruit developing commonly from syncarpous pistil (rarely from single carpel) with axile placentation.
• e.g., tomato, grapes, banana, guava, etc.

iii) Pepo

• Fleshy many seeded fruit like but it develops from inferior one celled or three celled syncarpous pistil with parietal placentation.
• e.g., cucumber, pumpkin, watermelon.

iv) Pome

• This is an inferior, two or more celled, fleshy, syncarpous fruit.
• Surrounded by the thalamus (fleshy edible part is thalamus).
• While the actual fruit lies within. e.g., apple, pear.

v) Hesperidium

• Superior, many celled fleshy fruit with axile placentation.
• Endocarp projects inwards forming distinct chamber.
• Epicarp and mesocarp fuse together and form a separable skin.
• Edible part is juicy placental hairs.
• e.g., Citrus spp. (orange, lemon).

vi) Balausta

• It is special type of false berry.
• Epicarp and thalamus fused to form leathery structure called rind.
• Mesocarp is plate like in-foldings in the fruit and endocarp is the membrane surrounding the juicy seeds.
• Edible part is juicy testa of seeds.

2) Aggregate fruits

• Collection of simple fruits developing from apocarpous pistil.
• Aggregate of simple fruits borne by single flower is known as etaerio.
• Etaerio of follicles: Michelia, Calotropis, Vinca.
• Etaerio of achenes: rose, lotus, strawberry.
• Etaerio of drupes: raspberry.
• Etaerio of berries: custard apple.

3) Multiple or composite fruits

• Fruits develop from the inflorescence.
• They are of following types. They are:

i) Sorosis

• Develops from spike, catkin or spadix inflorescence.
• e.g., pineapple, mulberry, jackfruit.

ii) Syconous or syconium

• Develops from hypanthodium inflorescence.
• e.g., Ficus spp (banyan, peepal, fig).

References: 

i) https://study.com/academy/lesson/fruit-definition-types-benefits-examples.html

ii) https://byjus.com/biology/fruit-formation-parts-types/

iii) https://www.biologydiscussion.com/plants/fruit-and-its-types-explained-with-examples/6398

Fruit and its type