5.6. The Fruit

The fruit is a characteristic feature of the flowering plants. It is a mature or ripened ovary, developed after fertilisation. If a fruit is formed without fertilisation of the ovary, it is called a parthenocarpic fruit.

In flowering plants, a fruit is what we recognize as a mature ovary that results from the fertilization process. The fertilization occurs when pollen meets the ovule in the ovary, which leads to the formation of seeds inside the fruit. Interestingly, some fruits can develop even if fertilization does not happen; these are known as parthenocarpic fruits. They can still grow and be edible, for example, bananas.

Consider a situation where you plant a seed and nurture it until it grows into a flowering plant. When the flower is fertilized, it develops into a fruit (like an apple), containing seeds that can grow into new plants. If you have a banana, it can also be thought of as a fruit that develops without fertilization, making it unique.

Generally, the fruit consists of a wall or pericarp and seeds. The pericarp may be dry or fleshy. When pericarp is thick and fleshy, it is differentiated into the outer epicarp, the middle mesocarp, and the inner endocarp.

Fruits are composed of two main parts: the pericarp, which is the fruit wall, and the seeds inside. The pericarp can vary in texture; it might be dry, like in nuts, or fleshy, like in peaches. When fleshy, the pericarp is usually divided into three layers—the epicarp (the outer layer), the mesocarp (the middle fleshy part), and the endocarp (the innermost layer that directly surrounds the seeds). This layered structure plays a crucial role in protecting the seeds and aiding in their dispersal.

Imagine biting into a peach. The juicy part you taste is the mesocarp, while the skin you first touch is the epicarp. The hard pit inside is the endocarp, which protects the seed. Each layer serves a different purpose, from attracting animals to eat the fruit and disperse seeds to providing protective barriers.

In mango and coconut, the fruit is known as a drupe. They develop from monocarpellary superior ovaries and are one-seeded. In mango, the pericarp is well differentiated into an outer thin epicarp, a middle fleshy edible mesocarp and an inner stony hard endocarp. In coconut which is also a drupe, the mesocarp is fibrous.

Fruits can be categorized into different types based on their structure and characteristics. A drupe, for example, is a type of fruit that has a single seed encased in a hard shell. In the case of mangoes and coconuts, both are classified as drupes. In mangoes, the fleshy part we eat is the mesocarp, while the hard part surrounding the seed is the endocarp. Coconuts share this structure, but instead of a fleshy mesocarp, they have a fibrous layer, which aids in water retention and its ability to float, ensuring seed dispersal via water.

Think of mangoes as nature's candy with a sweet, juicy exterior (the mesocarp) layered over a protective shell (the endocarp) that guards its valuable seed. Coconuts are like the beach's version of a fruit with a dense outer layer that floats on water, allowing the seed to travel long distances and take root on new shores.

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