problem of updating the tag name from new.html.erb ?

Hi All,
i have created tables called streams and tags.
Tags table is to assign the tag name to stream table entries.
to tag support i am using acts_as_taggable_steroids plugin.

if i want to create a new table entry from new.html.erb am able to add
and in the same page i am tring to enter the tag name to the stream
table entry but i could not see it is updating in tag table..

to do this i added piece of code in new.html.erb
           <b>Tags</b><br />
           <%= f.text_field :name %>

But if do edit using edit.html.erb i able to update the tag table

how to update the tag table entry in i am using
below code to edit the tagname in tag table
           <b>Tags</b><br />
           <%= f.text_area('tags_as_text') %>

thanks for reading the query.