Fruit | Definition, Description, Parts, Types & Examples

The flowering plants or the angiosperms are characterised by the presence of a fruit. After fertilisation the ripened or mature ovary is called fruit. Some fruits which are formed without fertlisation are called parthenocarpic fruits. e.g., Banana.

Parts of a Fruit

A fruit mainly consists of two parts namely fruit wall and seed.

(i) Fruit wall: Fruit wall or pericarp develops from the wall of the ovary. It can be dry or fleshy. If the pericarp is thick and fleshy then it differentiates into three different layers namely:

• (a) Epicarp (outer cover)
• (b) Mesocarp (middle layer)
• (c) Endocarp (innermost layer)

(ii) Seeds Develop from Ovules : In some plants ovary grows into fruit without fertilization, such fruits are called parthenocarpic fruits. They are seedless, e.g. Banana, Grapes.

The fruit which develops from ovary is called true fruit. Most of the fruits are true fruits. If any other floral part takes part in fruit formation, it is called false fruit (pseudocarp). e.g., Apple, Pear.

Simple fruit develops from the syncarpous ovary of the single flower with or without accessory parts. Aggregate fruits are formed from polycarpellary, apocarpous ovary. Each carpel develops into a fruitlet and all fruitlets together form an aggregate fruit. The multiple fruit develops from the entire inflorescence.

Types of Fruits

1. Simple Fruits

Fruit developing from the syncarpous ovary of the single flower with or without accessory parts is called simple fruit. Simple fruits are of following types

A. Dry indehiscent fruits. They do not split or burst. Seeds are liberated only by the decomposition or destruction of pericarp.

Types of dry indehiscent fruits

(i) Caryopsis: Develops from monocarpellary, unilocular ovary. Fruit wall or pericarp is completely fused with seed coat. e.g., wheat, maize, rice (Graminae). (ii) Achene: It develops from monocapellary, unilocular ovary. Fruit wall (pericarp) is not completely attached with seed coat (as that of caryopsis), e.g, Mirabilis. (iii) Cypsela: Develops from bicarpellary, unilocular and inferior ovary. Calyx is hair like and called pappus which helps in dispersal of fruits (seeds), e.g, Sunflower, Sonchus, Zinnia, Taraxacum. It is characteristic fruit of family Compositae (Asteraceae). (iv) Nut: Develops from polycarpellary superior ovary, Pericap is hard (stony) and sometimes woody, e.g., Anacardium (cashew nut), Litchi (marking nut), Trapa (water chestnut) and Quercus (oak).

B. Dry dehiscent fruits. These fruits burst automatically and discharge their seeds.

Types of dry dehiscent fruits

(i) Legume or pod: Dry, one chambered fruit developing from a superior and monocarpellary ovary. Mature fruit dehisces by both sutures or margins, e.g., Gram, lentil, pea. (ii) Siliqua: Develops from bicarpellary, unilocular ovary with parietal placentation, dehiscence of fruits occur by both the halves from base to apex, e.g., Mustard, radish. This is characteristic fruit of family Cruciferae or Brassicaceae. (iii) Silicula: A short, broad, flat siliqua with few seeds is known as silicula. e.g., Iberis, Capsella. (iv) Capsule: Develops from multicarpellary, syncarpous ovary. Dehiscence occurs by many ways. (a) By Pores: Porocidal, e.g., Opium (Poppy), Argemone. (b) By locules or valves: Loculicidal, e.g, Cotton. (c) By Septa. Septicidal, e.g., Linseed. (d) Septa breakdown into fragments: Septifragal, e.g., Datura.

C. Fleshy or Succulent fruits. These are of following types:

• (i) Drupe: Mostly one seeded fruits with pericarp differentiated into epicarp, mesocarp and hard and stony endocarp, e.g., Mangifera indica (Mango-epicarp forms skin, mesocarp-fleshy, juicy and edible, endocarp is hard and stony), Cocos nucifera (Coconut-Mesocarp is fibrous which is used in making coir so called as fibrous drupe), Juglans regia (walnut).

• (ii) Berry: One to many seeded fruits. Epicarp forms the outer skin. Middle thick and fleshy part is called mesocarp with a membrane like endocarp, e.g., Tomato, guava, papaya, grapes, banana, brinjal, chillies. Betel nut is a one seeded berry.
• (iii) Pepo (hard walled berry): Develops from tricarpellary, syncarpous, unilocular and inferior ovary. Epicarp forms skin of fruit. Mesocarp and endocarp are fleshy and edible. Sometimes, fruits are bitter in taste due to tetracyclic triterpenes e.g., Cucumber, gourd, watermelon.
• (iv) Pome: Develops from syncarpous inferior ovary which is surrounded by fleshy thalamus. So, true fruit lies inside the swollen fleshy and edible thalamus. It is false fruit or pseudocarp e.g., Apple, pear. Edible part is fleshy thalamus.
• (v) Hesperidium: Develops from multicarpellary, multilocular, syncarpous, superior ovary with axile placentation. The epicarp and mesocarp fused together to form skin or rind of the fruit. Endocarp projects inwards forming a number of distinct chambers. The juicy unicellular hairs are present on the inner side of the endocarp. e.g., Orange and all citrus fruits.
• (vi) Balausta: Develops from multilocular,syncarpous, inferior ovary. Epicarp is tough and leathery. Endocarp is membranous. Seeds are irregularly distributed inside the fruit. Juicy testa of the seeds is edible, The fruit has persistent calyx e.g., pomegranate.
• (Vii) Amphisarca : Develops from multicarpellary, syncarpous, multilocular and superior ovary. The epicarp is hard and woody, mesocarp, endocarp and swollen placenta are fleshy and edible e.g., Aegle marmelos (wood apple or bael), Feronia limonia (Kaith or elephant apple).

2. Aggregate Fruits

Aggregate fruits are formed from polycarpellary, apocarpous ovary. Each carpel develops into a fruitlet and all fruitlets together form an aggregate fruit. An aggregate of simple fruits borne by apocarpous ovary of a single flower is otherwise known as ‘etaerio‘. Aggregate fruits are of the following types:

(i) An etaerio of achenes e.g., Strawberry

(ii) An etaerio of berries e.g., Artobotrys

(iii) An etaerio of follicles e.g., Delphinium, Michelia

(iv) An etaerio of drupes e.g., Raspberry

3. Multiple or Composite Fruits

The multiple fruit develops from the entire inflorescence. These fruits are of two types:

(i) Sorosis: These fruits develop from spike, spadix or catkin inflorescence. The flowers fuse together by their sepals or perianth and the whole inflorescence forms a compact mass e.g., Jackfruit, mulberry, pineapple.

(ii) Syconus: This fruit develops from hypanthodium inflorescence e.g., Ficus sp. (F19. gular, banyan, peepal). The fruitlets are achenial in nature.

Edible parts of Some Common Fruits and their Types

Common/ English name Botanical Name

Type

Edible parts

1. Simple fruits

Pea

Pisum sativum

Legume

Seeds

Lady’s finger/Okra

Abelmoschus esculentus

Capsule

Entire fruit

Wheat

Triticum aestivum

Caryopsis

Entire fruit

Con/Maize

Zea mays

Caryopsis

Entire fruit

Cashew nut

Anacardium occidentale

Nut

Cotyledons and fleshy thalamus

Litchi

Litchi chinensis

Nut

Aril

Water chestnut

Trapa bispinosa

Nut

Seeds

Ground nut

Arachis hypogea

Lomentum

Seeds

Coriander

Coriandrum sativum

Cremocarp

Entire fruit

 

1. Aggregate Fruits

Strawberry

Fragaria vesica

Etaerio of achenes

Fleshy thalamus and seeds

Inner layer of pericarp and

thalamus

Custard apple

Annona squamosa

Etaerio of berries

II1. Multiple or Composite Fruits

Succulent perianth and

fleshy axis

Mulberryy

Morus alba and M.nigra

Sorosis

Pineapple

Fleshy axis, bracts, fused

perianth and pericarp

Ananas comosuS

Sorosis

Jack fruit

Artocarpus heterophyllus

Sorosis

Fleshy axis, bracts, perianth

and seeds

Fig

Ficus caica

Syconus

Fleshy receptacle or thalamus