1
My answer I found in search_api_solr module search_api_solr.api.php file. I used hook_search_api_solr_field_mapping_alter
/**
* Change the way the index's field names are mapped to Solr field names.
*
* @param SearchApiIndex $index
* The index whose field mappings are altered.
* @param array $fields
* An associative array containing the index field ...
Only top voted, non community-wiki answers of a minimum length are eligible
