If that is the case you will have to view the pollen of the SAME species, from the SAME flower in two different ways under the SAME SEM.  

1) Remove the pollen from the dried anthers and observe using the usual stub and coating protocols for the specimens.  These specimens will have some pollen coat residue but they will retain structures (opercula, some sexine sculptures) lost in cleaning.  The will also retain the shape of the grain without significant deflation,

2) Follow the standard but modern acetolysis protocols for cleaning the outside and inside of the grains then view following standard mounting and coating.  This series will lose some of the structures (see above) and deflate the exine but will allow you to see baculae rods and lacuna much more clearly without remains of the pollen coat.  SEM allows you a much closer observation of the sexine.  

I have never investigated plants or pollen inside an SEM, but normally it should be sufficient if you put the pollen onto a sample holder, for example a carbon sticky tape, and coat the pollen with a conductive layer. I would go with 50nm of carbon or gold, preferably by sputtering, to coat also shadowed areas. It is possible that I am horribly wrong and that there are standard procedures from Biologists, but the simple coating enables you to take decent SEM images of the pollen without charging.

Since you already dried your pollen, this should be enough. If you are interested in very small surface features in the range of 50nm, you should deposit a thinner coating, so you are not altering the surface by your gold or carbon.

Thank you sir, 

There are some standard procedure sir. I need to know which method is easy and best, since i have very little sample...

I agree with the answer of Dr Hoffman but will suggest that take out pollen from dried anthers and get them silver /gold coated on the buttons and examine after processing with different magnification as per the scanning machine used. 

What do you want to see?  Granted, the anthers are dried and so is the pollen but do you want to see the grains with pollen coat (pollenkitt) droplets remaining in lacunae or clinging to sexine sites?  If you do then proceed as directed by Dr Hoffmann.  On the other hand, if you want to see sculpturing and apertures devoid of occluding droplets of lipid (they will give you bulbous and/or smeared surface images) you will have to take the grains through one of the standard cleaning processes.  As pollen dries naturally the pollen coat droplets do tend to retreat down into the exine caves but it usually doesn't vanish entirely under the SEM

As I understand  he wants to study pollen morphology anf surface pattern of different pollen

The question is how you want to document the pollen? In dry or hydrated condition, because the appearance of the pollen changes remarkable, especially if you want to focus on the aperture area. 

The pollen preparation procedures are different for dry and hydrated pollen.

Here is a chapter about pollen preparation from the pollen terminology book Hesse et al, 2009; 

https://www.dropbox.com/sh/v0wl9ab77tliwz1/AAAp1ERgEKLS3AyoA-IqwOysa?dl=0

Which species do you want to examine?

I want to study surface morphology and structure of aperture area of one Acanthaceae member. I need to study in dry condition only.

If that is the case you will have to view the pollen of the SAME species, from the SAME flower in two different ways under the SAME SEM.  

1) Remove the pollen from the dried anthers and observe using the usual stub and coating protocols for the specimens.  These specimens will have some pollen coat residue but they will retain structures (opercula, some sexine sculptures) lost in cleaning.  The will also retain the shape of the grain without significant deflation,

2) Follow the standard but modern acetolysis protocols for cleaning the outside and inside of the grains then view following standard mounting and coating.  This series will lose some of the structures (see above) and deflate the exine but will allow you to see baculae rods and lacuna much more clearly without remains of the pollen coat.  SEM allows you a much closer observation of the sexine.  

I would just like to add that sputter coating may be over complicating matters, and sometimes adding expense.  It depends what kind of magnification your after of course.  You will get great results on many SEMs now without sputter coating assuming the sample is dry enough.  You remove that whole step and chances for things going wrong or interfering.  It also of course depends on the SEMs you have available but if you view your pollen at low kV (say 20) you should get very nice images. I have had very nice images of D. magna up to x300 and pretty good success up to 4k once you get past this you start lose some resolution but again this is highly dependent on the microscope. I would talk to your technician about this sort of thing. 

Again I have not worked with pollen but the same I assume would apply, but stand to be corrected, talk to your technician. 

Thanks to all..  I got good images after gold sputtering (dry pollen).

Hi all,

I found this discussion from the web because I am planning to do same work as Muhammed. I was wondering how you dry the samples? Are you drying the anthers (using FAA and EtOH) and then scratch the pollen away to carbon tape. Or are you air drying the pollen separately?

Thanks! 

Hope the SEM has servwd your purpose for pollen morphological examination and variability. 

Dear Dr. Kontturi,

methods of preparation of specimens for SEM is standardized in most publications including fixation and dehydration, critical point drying, mounting in stubs, coating and examination. please refer to the recent publication by Jones, C.G. (2012).