Extra fields in blog list
In this case, It's not posible make this with the plugin.Then we will should write a little code.
We will create a blog template.
In this case the id of extrafield is 1, we can get this number in the extrafield list. 
In the template folder we create a file html template.
For example:
/templates/[our template]/html/com_content/category/blog.php
/templates/[our template]/html/com_content/category/blog_item.php
/templates/[our template]/html/com_content/category/blog_children.php
/templates/[our template]/html/com_content/category/blog_links.php
Download this file and copy in your template category layout. REMEMBER, EDIT AND WRITE THE CORRECT ID EXTRA FIELD IN THE BLOG_ITEM.PHP FILE.
The only change in the blog_item.php is, a 20 line for load fieldsattach API and 144 for write a value of extra field.



