i resolved changing as below:
BundleConfig.cs:
bundles.Add(new StyleBundle("~/Content/OfficeCss").Include(
"~/Content/Office.Controls.css"));
bundles.Add(new StyleBundle("~/Content/themes/base/css").Include(
"~/Content/themes/base/jquery.ui.core.css",
"~/Content/themes/base/jquery.ui.resizable.css",
"~/Content/themes/base/jquery.ui.selectable.css",
"~/Content/themes/base/jquery.ui.accordion.css",
"~/Content/themes/base/jquery.ui.autocomplete.css",
"~/Content/themes/base/jquery.ui.button.css",
"~/Content/themes/base/jquery.ui.dialog.css",
"~/Content/themes/base/jquery.ui.slider.css",
"~/Content/themes/base/jquery.ui.tabs.css",
"~/Content/themes/base/jquery.ui.datepicker.css",
"~/Content/themes/base/jquery.ui.progressbar.css",
"~/Content/themes/base/jquery.ui.theme.css"));
bundles.Add(new ScriptBundle("~/bundles/jqueryui").Include(
"~/Scripts/jquery-ui-{version}.js"));
create.cshtml:
<div class="form-group">
@Html.LabelFor(model => model.StartDate, htmlAttributes: new { @class = "control-label col-md-2" })
<div class="col-md-10">
@Html.EditorFor(model => model.StartDate, new { htmlAttributes = new { @class = "date-picker" } })
@Html.ValidationMessageFor(model => model.StartDate, "", new { @class = "text-danger" })
</div>
</div>
@section Scripts {
@Scripts.Render("~/bundles/jqueryval");
@Scripts.Render("~/bundles/jqueryui");
@Scripts.Render("~/Content/themes/base/css");
<script type="text/javascript">
$(document).ready(function () {
$('#StartDate').datepicker();
})
</script>
}