22 fruit

However, all fruits do not ripen in the same manner. On the basis of their ripening process, fruits are classified as:

Climacteric Fruits Non-Climacteric Fruits

Silicle:

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

Silique:

Fruit more than twice longer than wide (Brassicaeae, e.g. stocks). Formed from one flower having a single ovary divided into two carpels, separated by a partition (septum) that bears the ovules/seeds; generally, the carpels separate when ripe, although a few separate between seeds along joints

Non-climacteric fruits

Fruits that do not ripen in response to ethylene,

Cytokinins are hormones which are mostly responsible for

cell division and differentiation. This results in added thickness to the fruit.

The combination of cytokinins increasing the number of

cells and gibberellins increasing the size of those cells leads to spectacular enlargement of the fruit.

Ripening is associated with

change in composition i.e. conversion of starch to sugar.

It needs to be ripened before

consumption.

As seeds develop inside the ovary wall, they produce

cytokinins that migrate from the seed and promote cell division in the ovary wall.

Parthenocarpic fruit parthenocarpy:

development of fruit without fertilization. The fruit resembles a normally produced fruit but is seedless. examples (banana, long english cucumber, seedless grapes)

The seeds pass through their digestive tract and are

dispersed or disseminated away from the parent plant.

Dry fruits have other means of dissemination. For instance, the dandelion has evolved a

dry, feathery fruit to take advantage of the wind for dissemination.

The seeds have a

drying seed coat (the former integument of the ovule) and contain a mature embryo.

Fleshy fruits, like the tomato or apple, hold juices that prevent the seeds from

drying until they are mature.

A berry has an

entirely fleshy ovary. Tomato, date, blueberry, banana, pepper, and cranberry are examples of berries.

Most species must produce

ethylene in order for the fruit to ripen.

Fruits will ripen in response to

ethylene.

Three major parts of the pericarp are

exocarp mesocarp endocarp.

A pome has a

fleshy exterior and a center with papery carpels. Apples and pears are pomes.

A drupe is a fruit with a

fleshy exterior and a single hard, stony pit surrounding the seed. Cherry, peach, olive, and plum are examples of plants with drupes.

The fruit may be either

fleshy or dry

The surrounding ovary wall enlarges and forms a

fruit around the seeds.

Many things happen between the time of fertilization and the ripening of the fruit. The processes associated with

fruit development are dictated by plant hormones.

Climacteric Fruits are defined as

fruits that enter 'climacteric phase' after harvest i.e. they continue to ripen off the tree/plant.

Dehiscent fruits are

fruits that split open upon maturation.

Eventually, the fruit reaches

full size.

As the ovary wall thickens, the developing seeds begin to produce either

gibberellins or auxins, depending on the species. These hormones cause cells to enlarge and the ovary wall to expand.

The seed embryos are prevented from

growing until the seeds have been removed from the fruit or the abscisic acid in the seed breaks down

A nut is a

hard, one-seeded fruit. Oak, walnut, almonds, and hickory produce nuts.

These are

harvested hard and green, but fully mature.

Simple fruits are defined as

having developed from a single ovary of a single pistil. Simple fruits are often classified as being fleshy or dry.

Fleshy fruits also serve to

help disperse the seeds.

Dry fruits may be

indehiscent or dehiscent.

Fleshy fruits are

juicy. Berries, hesperidium, pepo, drupes, and pomes are categories of fleshy fruits.

A hesperidium fruit has a

leathery rind. Examples include oranges, grapefruits, lemons, and limes.

Many times a vegetable will be confused with a fruit. Technically, a fruit is a

mature, ripened ovary.

A capsule is composed of

more than one carpel that are united and form many-seeded fruits. The fruit of okra and cotton are capsules. Plants in the mustard family have a specialized form of capsule called a silique.

Cytokinins produced by the developing ovules cause

nutrients to be stored in the endosperm tissues of the developing seed. In many species, these nutrients are later translocated to the cotyledons.

Aggregate fruits develop from

one flower that contains several ovaries, each of which develops into a small fruit. These small fruits are joined tightly together to make a larger fruit.

An achene is one-sided fruit with a seed attached at

only one place to the pericarp. Sunflowers and strawberries have achene type fruit.

The ripening process could take a few days after

picking or it could depend on an environmental cue.

An example of multiple fruit is a

pineapple. Each section of a pineapple was an individual fruit from an individual flower, but they have fused to form the pineapple. Another example is the fig.

The two main functions of fruit are to

prevent the seeds from drying and to disperse the seed.

Schizocarp splits when

ripe into two achene-like mericarps; carpels not dehiscing to release seeds (Apiaceae e.g. fennel)

once harvested, non climateric fruits do not

ripen further.

There is great diversity of fruits. Three major divisions include:

simple fruits aggregate fruits multiple fruits.

Legume (pod) is composed of a

single carpel and has two longitudinal sutures. Soybeans, green beans, and peas are legumes.

Follicle is composed of a

single carpel and splits open along one suture. Milkweed fruit is a follicle.

A samara is usually

single seeded with a membranous wing. Examples are maple, elm, and ash.

A nutlet is a

small version of a nut. Birch and pecans are examples.

Fruit at this stage tends to be

sour (acid), mealy (starchy), green, hard, and lack fruity odor.

Indehiscent fruits or those that do not

split open at maturity and usually contain one or two seeds.

A caryopsis is similar to an achene. However, the pericarp

sticks or clings to the seed. Corn, rice, barley, rye, amaranth, sorghum, oat, and wheat have caryopsis fruit.

The fruit becomes

sweeter, less green and softer.

Ethylene diffuses throughout the fruit tissue and into

the atmosphere around the fruit. An increase in the rate of cellular respiration in the fruit cells and synthesis of new enzymes usually accompanies the ripening process.

Ripening is done near

the consumption areas

In some accessory fruits, for example in pomes or strawberries, the receptacle gives rise to

the edible part of the fruit.

The endocarp is

the inner part of the pericarp. It surrounds the seed or seeds. It may be hard like a peach or soft like a grape.

The mesocarp is

the middle layer of the pericarp. It often makes up the bulk of the fruit and is fleshy.

The exocarp is

the outer wall of the fruit. The exocarp, sometimes called the epicarp, forms the tough outer skin of the fruit. It can be thick and tough, as in the case of oranges, or thin and soft, like a grape.

The tissue that surrounds the seeds is called

the pericarp, or fruit wall.

Although dry fruits are not fat and juicy like the tomato, they do help prevent

the seed from drying.

This dissemination of seed is an important evolutionary trait for

the survival of the plant species.

The receptacle is

the thickened part of a stem from which the flower organs grow.

Many think that grapes are multiple fruits. However, grapes grow in clusters, but

they are not compound fruits. Each grape grew from one ovary in one flower, and each grape remains an independent fruit.

A pyxis is a

type of capsule with a lid that falls from the fruit. An example is purslane.

After the fertilization of flowering plants, the ovule develops into

a seed.

Meanwhile, the plant produces

abscisic acid, which causes the embryo in the developing seeds to become dormant.

For example, some animals are attracted to the nutritious fruit and eat the seeds

along with the fleshy fruit.

Some types of indehiscent fruits are:

Achene Caryopsis Samara Nut Uricle Nutlet.

Dehiscent fruit types are:

Legume Follicle Capsule Pyxis.

Examples of climacteric:

Mango, Banana, Papaya, Guava, Sapota, Kiwi, Fig, Apple, Passion fruit, Apricot, Plum, Pear

Non climacteric Examples:

Orange, Mosambi, Kienow, Grape fruit, Grapes, Pomegranate, Litchi, Watermelon, Cherry, Raspberry, Blackberry, Strawberry, cashew, lemon

At about this stage, the enlarged ovary can be called

a fruit, and the ovules have become mature seeds.

A pepo is a type of fruit defined by

a hard rind and a fleshy inner matrix. Watermelons, cantaloupe, squash, and pumpkins are pepos.

Multiple fruits consist of

a number of flowers that fused to form a mass.

Ripening is

a process in fruits that causes them to become edible.

An example of aggregate fruit is

a raspberry. Each fleshy lobe in a raspberry is actually an individual fruit, but they are joined at their bases. Strawberries are an aggregate of achenes.