Please have a look at this useful PDF attachment.

Check the AOAC (Association of Official Analytical Chemists) too.  They have a section on soil analysis.  As I recall it was turbidimetric method using a solution of Barium Chloride in Glycerin.

You also need an extracting solution and it is typically a phosphate salt to displace sorbed sulfate,  Look at some standard methods for soils

Thank you! I will let you know the results.

we need extraction at a large scale with great accuracy and a multi power kit..... especially when we are commenting through a Pakistani plate form. 

All of the soil methods are heavily dependent upon the sample preparation method used. You will get radically different results depending upon how you prepare your sample for analysis. I prefer the American Society of Agronomy method; they have a real basis for their insistence on using a saturated paste extract. The final analytical method is easy and cheap - just use turbidimetry with barium chloride (several methods available for that). But be very careful, and very reproducible, with your extraction method.

Displacement by phosphate, acidification, and measurement as BaSO4 works fine if you are interested only in sulfate. The question is more complex if you are interested in plant available S. For that purpose a less specific measure seems to work better, e.g. see 'KCl 40', which is an ICP measure on a warm KCl extract.