how to add next and previous link on content full display page on tpl file in drupal 7? I have a content type called flower and I have created a node--flower.tpl.php for displaying products.

I am also using category of flowers. I need to add next and previous links on this page for a specific category. For example if I'm on rose page then all roses are needed to show on next and previous link, not other category data.
You will have to write this logic yourself in a hook_preprocess_node(). This code should be added to the template.php file of your front end theme.

Here's an example:

function YOUR_THEME_preprocess_node(&amp;$variables) {
  // Perform the logic for selecting prev/next terms here. Install and use
  // the Devel module to see what is available to you and to debug the code.

  // See what's available:
  dpm($variables);

  // Load a sample term. Note: this should be different if your website is
  // in multiple languages. Below is just an example.
  $term = taxonomy_term_load($variables['node']-&gt;field_term[LANGUAGE_NONE][0]['tid']);

  // Pass a variable to the node--flower.tpl.php file. Code below will make
  // the $previous_category and $next_category variables available in the
  // node--flower.tpl.php file.
  $variables['previous_category'] = 'Your link here';
  $variables['next_category'] = 'Your link here';
}