Question

What is pollen viability?

Answer 1

Hint: The ability of pollen to pollinate the flower when it comes in contact with the stigma of the flower. It can be induced or deduced by using various chemicals and pollination can be stopped by several techniques.

Complete answer:
The pollen viability is the ability of the pollen to transfer the male gametes produced by them to the embryo sac for pollination. Pollen sare produced in the anthers of male reproductive part stamens in the flowers. When the anthers get matured they will form many pollen grains inside them, these pollen grains after maturity will release male gametes which are then transferred to the female embryo sac for pollination. These pollens have different viabilities depending upon the various species and their habitats and conditions they live in. The quality of pollen is checked on the basis of its viability and vigor, the more the viable pollen is the more qualitative it is.
The viability of pollen is generally measured by the staining technique inside a laboratory. In this method, a large number of pollens of a particular flower is taken on a slide, and then it is stained by acetocarmine stain. This results in the pollens dyeing red in color while certain pollens will remain colorless. The colored and colorless pollen are counted and then their ratio is calculated which will give the pollen viability of a particular flower. The other method is the hanging drop method performed in-vitro. Here a slide having a small curve is taken where pollen along with the mixture of water and certain chemicals are kept and a slide cover is placed on top of it. Keep it undisturbed for some time and then observe. It will be observed that the pollen tubes are developed in the pollen after germination and thus proving them to be viable pollen.

Note:
There are various other experiments that are performed to distinguish between the pollen grains of monocotyledons and dicotyledons by studying their characteristic features and their shape and size. If the pollens are not viable then they will not perform pollination and are termed sterile.