修改%theme%/function.php文件，增加以下代码：

function close_comments( $posts ) {
    if ( !is_single() ) { return $posts; }
    if ( time() - strtotime( $posts[0]->post_date_gmt ) > ( 1 ) ) {
        $posts[0]->comment_status = 'closed';
        $posts[0]->ping_status    = 'closed';
    }
    return $posts;
}
add_filter( 'the_posts', 'close_comments' );