Definition of Pollen Pistil Interaction

Pollen is a fine, powdery substance, usually yellow in colour. It consists of numerous microscopic grains called pollen grains. Pollen is discharged from the male reproductive part of a flower, known as the androecium. It contains the male gametes, which fuse with the female gametes to form a zygote, and eventually offspring. 

The pistil is the female reproductive part of the flower, also known as a gynoecium. It consists of a swollen part at the base of the ovary which contains the female zygote. This is followed by a long stalk known as the style, which ends in a tip called the stigma.

For reproduction to take place, the male gamete in the pollen must come in contact with the female gamete in the ovary. This happens by the process of pollen pistil interaction. Pollen pistil interaction is when the pollen comes in contact with the pistil(specifically the style or the tip of the pistil) and then the male gamete makes its way into the ovary, where the fusion of the two gametes takes place. 

In order to figure out the definition of pollen pistil interaction, one must first learn about the two parts of the plant that make it possible- the pollen and the pistil.

Pollen

Pollen is the substance released by the male reproductive part of the flower known as the androecium. The androecium is made up of two parts- The anther and the filament. The filament is a long thin stalk, at the end of which is attached two bean-shaped structures known as the anthers, which produce and discharge pollen.

Pollen consists of microscopic grain-like structures called pollen grains. A pollen grain contains the pollen tube cell and two male gametes. These cells are covered by a wall that has two layers- the inner intine and the outer exine. The exine is a hard, trough layer that is chemically very resistive. This ensures that the pollen grain does not get damaged when exposed to the atmosphere.

The transport of pollen from the male anther to the female pistil is called pollination. Pollination is carried out in various methods like wind pollination, where pollen is blown away by the wind, or by insect pollination, where the pollen is transported from one flower to another by insects like bees, butterflies, etc. 

Pistil

A pistil is the female reproductive part of a flower, also known as the gynoecium.  The Pistil consists of two parts- a style, a stigma, and an ovary.

The stigma is at the uppermost tip of the pistil. It is a knob-like part that receives pollen for fertilisation. It is usually sticky in nature so that the pollen can stick to it.

The style is the long stalk-like structure branching out of the stigma. Inside it is a long tube that facilitates the transport of the male gamete to the ovary.

The Ovary is the swollen structure at the base of the pistil. It is the main component of the pistil as it is the sight of fertilisation. The ovary is divided into small segments called ovules. It is inside these ovules that fertilisation takes place. When a flower matures, it is this ovary that grows into the fruit part, inside which are the seeds. The ovules turn into seeds. The number of ovules in an ovary, therefore, depends upon the type of flower. 

Pollen Pistil Interaction

Pollen pistil interaction refers to the whole process that takes place from the time pollen is received in the pistil to the time of fertilisation. If we take into account all the steps, we will be able to figure out what the definition of pollen pistil interaction is. 

• The first step is the receiving of the pollen into the pistil. This happens due to pollination. Pollen from the male anther is carried by environmental agents (wind and insects) and is received by the female stigma. The stigma then carries out a sort of “selection process”, through different chemical reactions, and inactive pollen or pollen of other species are destroyed.
• The next step is germination of the pollen tube. The pollen tube cell inside the pollen grain now gets activated by several chemicals secreted by both the style and the stigma, and starts to grow into a long tube-like structure known as the pollen tube. The pollen tube enters the ovary, and then the ovules.
• The two male gametes then enter the ovules, and fertilisation takes place inside the ovules.

The definition of pollen pistil interaction therefore turns out to be- The process in which the female pistil and the male pollen go through various chemical interactivities to facilitate the transport of male gamete into the ovary for fertilisation. This might also work as a short note on pollen pistil interaction.

Conclusion

Pollen is a fine, powdery substance, usually yellow in colour. It consists of numerous microscopic grains called pollen grains. Pollen is discharged from the male reproductive part of a flower, known as the androecium. It contains the male gametes, which fuse with the female gametes to form a zygote, and eventually offspring. 

A pistil is the female reproductive part of a flower, also known as the gynoecium.  The Pistil consists of two parts- a style, a stigma, and an ovary.

The stigma is at the uppermost tip of the pistil. It is a knob-like part that receives pollen for fertilisation. It is usually sticky in nature so that the pollen can stick to it.