AJAX second SELECT population (Laravel Dynamic Dropdown)

gistfile1.php

// Routes.php : 

/* AJAX Select DropDown Population */

Route::get('api/dropdown', function(){
	$input 	= Input::get('catselect');
	$cat 	= Category::find($input);
	$subcategory = $cat->subcategory();
	return Response::make($subcategory->get(['id','subcat_name']));
});

// Category.php (Model)


class Category extends Eloquent {
   
   public function Subcategory(){
      return $this->hasMany('Subcategory');
   }

   public function Seed(){
      return $this->belongsTo('Seed', 'seed_category');
   }
}

// Subcategory.php (Model)

class Subcategory extends Eloquent {
   
   public function Category(){
      return $this->belongsTo('Category');
   }

   public function Seed(){
      return $this->belongsTo('Seed', 'seed_subcategory');
   }
}

// Seed.php (Model)
class Seed extends Eloquent {
 
  
  public function source() {
    return $this->belongsTo('Source', 'id');
  }

  public function category() {
    /* seconad argument is row in target table*/
    return $this->hasOne('Category', 'id');
  }

  public function subcategory() {
    return $this->hasOne('Subcategory', 'id');
  }
}

//new.blade.php (View)
            <div class="row">
              <div class="col-md-6">
                <div class="form-group">
                   <span class="formlabel">Kategorie *</span>
                    <label class="select">
                      <select class="form-control" id="seed_category" name="seed_category" data-url="{{ url('api/dropdown')}}">
                      <option value="0" selected disabled="">Bitte aus Liste wählen</option>
                      @foreach ($catlist as $category)
                        <option value="{{$category->id}}" >{{$category->cat_name}}</option>
                        @endforeach
                      </select>
                      <i></i>
                    </label>
                </div>
              </div>
             <div class="col-md-6">
                <div class="form-group">
                   <span class="formlabel">Unterkategorie *</span>
                    <label class="select">
                      <select class="form-control" id="seed_subcategory" name="seed_subcategory">
                      <option value="0" selected disabled="">Bitte zuerst eine Kategorie wählen</option>
                      </select>
                      <i></i>
                    </label>
                </div>
              </div>
            </div>
            
            <script type="text/javascript">
    $(function() {

        // Autopopulate Subcategories Select Drop down
        $('#seed_category').change(function(){
          $.get($(this).data('url'), 
              { catselect: $(this).val() }, 
              function(data) {
                  var subcat = $('#seed_subcategory');
                  subcat.empty();

                  $.each(data, function(index, element) {
                      subcat.append("<option value='"+ element.id +"'>" + element.subcat_name + "</option>");
                  });
              });
        });