[shan]

see customer/buny_now.tpl

and see this

<SELECT name="amount">
{if $product.min_amount le 1}
{assign var="start_quantity" value=1}
{else}
{assign var="start_quantity" value=$product.min_amount}
{/if}
{section name=quantity loop=$mq start=$start_quantity}
<OPTION value="{%quantity.index%}" {if $smarty.get.quantity eq %quantity.index%}selected{/if}>{%quantity.index%}</OPTION>
{/section}
</SELECT>

also see here on how to use the step function within a section

http://smarty.php.net/manual/en/language.function.section.php