In this article we will discuss about the meaning and advantages of pollen culture.
Meaning of Pollen Culture:
Microspore or the immature pollen can be used as the explant to get the haploid plants directly. For pollen or microspore culture the flower buds are collected, surface sterilized and the anther lobes are dissected out from the flower buds as before. Then the anther lobes are squeezed with the help of a scalpel within a tube or small beaker to collect the microspore or pollen in nutrient media.
Then the anther tissue debris is removed by filtering the suspension through a nylon sieve with a diameter slightly larger than the pollen size (40µ-100µ) allowing the microspore only to pass through it.
Then the microspore-suspension washed and concentrated to a plating density. The microspores obtained are then mixed with an appropriate culture medium at a density of 103— 104 microspore/ml, and plated in small petriplate.
To ensure good aeration, the layer of liquid in the dish should be as thin as possible, and sealed with ‘parafilm’ to avoid dehydration. The responsive pollen will divide and form embryos or calli which directly or indirectly will form the haploid plantlet. By following the method of sub-culturing the whole plant suitable for soil transfer can be obtained (Fig. 21.3A-B).
Advantages of Pollen Culture:
The main disadvantage of anther culture is that the plants or embryos or calli not only originate from microspore or pollen but may also originate from various other parts of anther lobes (anther wall, nucellus, tapetum) which are diploid tissues.
Furthermore, anther wall or other tissue may affect the way of androgenesis by inhibiting the penetrance of media or stimulating effect of hormones supplied. This difficulty can be avoided by culturing the isolated microspores or pollen.
This method has the following advantages:
(i) The explants i.e., microspores or pollens are all haploid cells.
(ii) The sequence of androgenesis can be observed starting from a single cell.
(iii) The microspores are ideal for uptake, transformation and mutagenic studies, and the microspores are evenly exposed to chemicals and physical mutagens.
(iv) Higher yields of plants/anther could be obtained.