Use the main loop, not a custom loop. Customize the loop parameters using 'pre_get_posts' in functions.php.

functions.php

<?php


/**
 * Customize Product Category Query
 * @link http://www.billerickson.net/customize-the-wordpress-query/
 */
function be_product_category_query( $query ) {
  if( $query->is_main_query() && !is_admin() && $query->is_tax( 'product-category' ) ) {
    $query->set( 'orderby', 'title' );
    $query->set( 'order', 'ASC' );
    $query->set( 'posts_per_page', '-1' );
  }
}
add_action( 'pre_get_posts', 'be_product_category_query' );

taxonomy-product_category.php

<?php


remove_action ('genesis_loop', 'genesis_do_loop');
add_action( 'genesis_loop', 'jm_custom_do_loop' );

function jm_custom_do_loop() {

	if( have_posts() ):
		echo '<ul>';
		while ( have_posts() ) : $loop->the_post();
			echo '<li><a href="' . get_permalink() . '">' . get_the_title() . '</a></li>';
		endwhile;
		echo '</ul>';
	endif;
}





genesis();