Hello Anandh,
I believe your missing a quotation at the end of
+"</method>"
That would produce a strqry ending in
</Method>+ with no closure of your batch tag nor an end of line.
string myGuid = lstIndustry.ID.ToString();
string strqry = "<?xml version=\"1.0\"encoding=\"UTF-8\"?>"
+ "<Batch>"
+ "<Method ID='A1'>"
+ "<SetList>" + myGuid + "</SetList>"
+ "<SetVar Name='ID'>122</SetVar>"
+ "<SetVar Name='Cmd'>Delete</SetVar>"
+"</Method>
+"</Batch>";
pwsite.RootWeb.ProcessBatchData(strqry);