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Home , Aggregate fruit, Multiple fruit

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FRUITS • A may be defined as a fertilized (mature) . After fertilization an ovule becomes a seed, and ovary swells up and becomes the fruit. • In some cases, however, the ovary may ripen and develop into a fruit without fertilization, such a phenomenon is said to be parthenocarpy. Banana is a very good example of parthenocarpic fruit. There are no seeds in the fruit hence they are also called as seedless . • Basically, fruits are of two types such as true fruits and false fruits. • True fruits are those where ovary develops into the fruit. In false fruit, also called as the pseudo fruits, any part of the , other than ovary, after fertilization becomes swollen and looks like a fruit. • Apple and cashew fruits are typical false fruits. In apple and cashew nut the thalamus or becomes fleshy and edible.

CLASSIFICATION OF FRUITS  Fruits are classified into following three categories, namely -

I. SIMPLE FRUITS: A simple fruit is one that develops from a monocarpellary or multicarpellary ovary of a single flower. In other words only one fruit develops (separately) from one ovary.

 Simple fruits are again classified in to two types, based on the nature of the fruit wall (pericarp). These are

a. SIMPLE FLESHY (SUCCULENT) FRUITS

b. SIMPLE DRY FRUITS

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

2 | P a g e a. SIMPLE FLESHY FRUITS: In fleshy or succulent fruits, the fruit is fleshy and juicy. These are indehiscent. The fruit wall is generally distinguishable into three layers namely the outer epicarp, the middle mesocarp and the inner endocarp.

1. : It is a simple fleshy fruit develops from syncarpus superior ovary with axile placentation, generally many seeded. The pericarp has an outer thin epicarp and an inner fleshy mesocarp and sometimes even the endocarp is fleshy in which the seeds are embedded. e.g. Tomato, Brinjal, Grape, kiwi.

2. : It is a simple fleshy fruit develops from a syncarpous inferior ovary having axile placentation. The pericarp is differentiated into outer thick, leathery epicarp having a number of oil glands, the middle white, spongy mesocarp closely attached to the inner side of the epicarp and the inner membranous endocarp projecting inwards forming distinct chambers. From the inner wall of the endocarp grows out numerous, thick, swollen hairs containing a syrupy juice. They are edible. e. g. Citrus fruits like Orange, Lemon, etc

3. : It is a simple fleshy false fruit, develops from a syncarpous inferior ovary having axile placentation. After fertilization, the thalamus becomes fleshy and edible. But the actual fruit lies within. e.g. Apple.

4. : It is a simple fleshy fruit enclosing one or more seeds. The pericarp is differentiated into outer epicarp, the middle fleshy or sometimes fibrous mesocarp and inner hard and stony endocarp. e.g. Mango, Cherry, Apricot, Avocado and Coconut.

5. PEPO: It is a simple fleshy fruit and generally many-seeded. It develops from an inferior, monolocular ovary, having parietal placentation. E.g. Cucumber, Watermelon.

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

3 | P a g e b. SIMPLE DRY FRUITS: In dry fruits, the wall cannot be distinguished into three layers. 1. DRY DEHISCENT FRUITS: In dry fruits, at maturity the pericarp may split or break open to liberate the seeds. Such fruits are called dry dehiscent fruits. Some of the common types of simple fruits are as follows a. or pod: It is a simple, dry, dehiscent fruit develops from the monocarpellary, monolocular ovary having marginal placentation. At maturity, the pericarp splits along both the margins (sutures) to liberate seeds. e.g. Pea, Bean, etc.

b. or Pair of Follicle: It is a simple, dry, dehiscent fruit developing from the monolocular ovary having marginal placentation. The pericarp dehisces along only the ventral suture to liberate seeds. e. g. Calotropis, Vinca.

c. Siliqua: It is a simple, dry, dehiscent fruit developing from the bicarpellary ovary. The ovary which is bilocular in the begining and becomes tertralocular due to the development of a false septum called replum. The fruit break opens on both the valves with the seeds remain attached to the central replum. e.g. Mustard, Radish.

d. Silicule: A simple dry dehiscent fruit, similar to siliqua, but contains just a few seeds and the replum is much shorter and flattened. e.g., Capsella, Lepidium.

e. : It is a simple, dry, dehiscent fruit developing from the syncarpous ovary having axile placentation. The capsules are variously named according to their mode of . e.g., Lady's finger, Cotton, Datura, poppy etc.

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

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2. DRY INDEHISCENT FRUITS: These fruits do not dehisce but the seeds are released only after the decay of the pericarp. a. : It is simple, dry, indehiscent fruit developing from a superior monolocular ovary with a single ovule. The pericarp is dry, membranous and free from the seed coat. E.g. Mirabilis, Buttercup (Ranunculus), Clematis

(Clematis), Coreopsis, etc.

b. : It is a simple, dry, indehiscent fruit developing from monocarpellary ovary with a single ovule. The pericarp is fused with the seed coat. E.g. , Rice, Wheat.

c. Cypsela: It is a simple, dry, indehiscent fruit developing from inferior, bicarpellary, syncarpous, monolocular ovary with a single ovule. The pericarp is thin and free from the seed coat.

E.g. Helianthus.

d. Simple : It develops from a monocarpellary pistil with a superior, unilocular and uni-ovuled ovary. The pericarp is expanded in the form of wings which help in dispersal.

E.g. Holoptelea and Elm

e. Nut: Nut is very same in structure to the achene

and the ovary wall is tough and woody. i.e. they are

the fruits with a hardened pericarp, covered with

a cupule at the base.

E.g: Anacardium and Chestnut (Castanea sativa).

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

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3. DRY SPLITTING OR DRY SCHIZOCARPIC FRUITS: Here, the fruit dehisces into units called mericarps. Mericarps in turn split to release the seeds.

a. Lomentum: It is a simple, dry, schizocarpic fruit. The fruit is constricted or partitioned between seeds into a number of one-seeded compartments. The fruit breaks into one seeded indehiscent segment. e.g. Mimosa pudica, Acacia arabica, etc.

b. Cremocarp: This is a two-seeded fruit derived from bicarpellary, syncarpous, inferior, bilocular and uniovuled ovary. It is a typical fruit of family umbelliferae. The two mericarps split along the central axis or carpophore to which they remain attached. Persistent style and stylopodium are present. The two mericarps remain attached to a forked axis called carpophore. E.g. Coriander.

c. Regma: It is derived from polycarpellary pistil which splits into as many Cocci (dehiscent segments) as there are carpels. Regma of castor breaks up into three cocci as it is derived from tricarpellary syncarpous pistil. Similarly, regma of Geranium breaks into five cocci as it is derived from five carpels. E.g. Caster, Hura crepitant

d. Carcerulus: This fruit is derived from superior, syncarpous pistil, multilocular with axile placentation. The fruit splits into many mericarps. e.g. Hollyhock (Althaea rosea), Salvia, Ocimum, Abitilon and Malva.

e. Compound Samara: This is a type of two or more- chambered fruit derived from a syncarpous (i.e., compound) ovary. The pericarp is extended in the form of wings and at maturity the fruit breaks up % into single seeded mericarps.

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

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II. AGGREGATE FRUITS: A fruit that develops from a single flower with many separate carpels, thus each carpel produces a single fruit. As the individual fruits grow, they fuse together forming a single structure. Such an aggregate of simple fruits is also known as an etaerio. There are different types of aggregate fruits. Some of them are

a. Etaerio of follicles: In this case fruit develops from a bicarpellary apocarpous (e.g., in Calotropis) or tricarpellary (e.g., in Aconitum) or polycarpellary apocarpous (e.g., in Michelia) . In Asclepias and Calotropis each etaerio consists of a pair of follicles. In Aconitum an aggregate of three follicles is produced on the top of the thalamus, whereas in Michelia numerous follicles are developed on an elongated thalamus. e.g. Michelia.

b. Etaerio of : This type of fruit develops from polycarpellary apocarpous gynoecium. For example, in Clematis and Naravelia the achenes are provided with feathery and persistent styles, in Rosa the achenes remain enclosed in a hollow, receptacular thalamus, in Fragaria the achenes are found on the fleshy thalamus and in Nelumbo the fruitlets occur on a flat, top-shaped spongy thalamus e.g. , Clematis

c. Etaerio of : The characteristic example of this type is found in Rubus (). It develops from superior, polycarpellary and apocarpous gynoecium. The carpels are borne on a conical thalamus. Here a number of small drupelets develop from separate carpels of a flower and they are grouped together on a fleshy thalamus. e.g. Rubus fruticosa.

d. Etaerio of : In this type of fruit each carpel of an apocarpous pistil develops into a berry. During development the margins of the carpels may be fused (e.g., in squamosa) or they may remain separate from each other (e.g., in Artabotrys odoratissimus). In Annona squamosa the mesocarp of berries is edible. In Annona the fruit is an aggregate of berries. The berries fuse during development to form a single large . In Polyalthia and Artabotrys the berries are free from one another.

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur

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III. MULTIPLE OR COMPOSITE FRUITS: If the entire develops into a single fruit, it is known as a multiple or composite fruit. There is a common envolope for the entire fruit. Such a fruit is also known as . There are three common types of multiple fruits.

a. Sorosis: This type of develops from a spike or spadix. Here the fuse together by their perianth lobes and simultaneously the axis bearing them becomes fleshy and juicy, and as a result the whole inflorescence forms a compact mass, e.g., pine apple, jack fruit, etc. Morus (mulberry), the perianth lobes become thick and juicy and are edible. Here the ovules do not mature into seeds and therefore, the carpels develop into small nutlets that are seedless. Eg. Morus (mulberry), Pineapple and Jack fruit.

b. Syconus: This type of composite fruit is a characteristic of the genus and is derived from entire inflorescence called the hypanthodium. In this case after fertilisation the hollow deep cup shaped receptacle becomes fleshy and juicy which encloses numerous minute male and female flowers. The receptacle develops further and converts into the so-called edible fleshy fruit. It really encloses a number of true fruits or achenes which develop from the female flowers of the hypanthodium inflorescence, e.g., Fig, Banyan and many species of Ficus.

c. Morinda fruit: It is a multiple fruit developed from the inferior ovaries of the flowers in an inflorescence. The ovary of each flower develops into a one seeded berry. All the berries are united to form a single compound fruit.

Dr Ashwathanarayana R, Guest faculty, Dept of Botany, SSCASCW, Tumkur