.....
$builder
            ->add('repDate','datetime',array(
                'widget' => 'single_text',
                'format' => 'dd.MM.yyyy HH:mm',
                'attr' => array('class' => 'input-medium dtp'),
                'required'  => true, 'label' => 'Дата рапорта',
                //'view_timezone' => 'Asia/Yekaterinburg',
                //'model_timezone' => 'Asia/Yekaterinburg'
            ))
....

..........
<td>{% if entity.fromDate %}{{ entity.fromDate|date('d.m.Y H:i') }}{% endif %}</td>
<td>{% if entity.toDate %}{{ entity.toDate|date('d.m.Y H:i') }}{% endif %}</td>
..........