<select class="form-control selectpicker" id="select1">
<option value="3">3</option>
<option value="2">2</option>
<option value="1">1</option>
</select>
$('#select1').bind('change', function(event) {
var i= $('#select1').val();
if(i=="1")
{
$('#time').show();
}
elseif(i=="2")
{
$('#time').hide();
}
});