Skip or remove Null Rows from DataTable using LINQ in C# .Net

I am having some null rows in my Cities table and i have not shown the Null values In the DropDownList

HTML

<asp:DropDownList ID="ddlCities" runat="server">
</asp:DropDownList>

Namespace

using System.Configuration;
using System.Data.SqlClient;
using System.Data;

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.PopulateDropDownList();
    }
}
private void PopulateDropDownList()
{
    string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    using (SqlConnection conn = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT CityName FROM Cities", conn))
        {
            using (SqlDataAdapter da = new SqlDataAdapter(cmd))
            {
                DataTable dt = new DataTable();
                da.Fill(dt);
                IEnumerable<DataRow> query = from city in dt.AsEnumerable()
                                            where !string.IsNullOrEmpty(city.Field<string>("CityName"))
                                            select city;

                // Create a table from the query.
                DataTable boundTable = query.CopyToDataTable<DataRow>();

                this.ddlCities.DataSource = boundTable;
                this.ddlCities.DataValueField = "CityName";
                this.ddlCities.DataTextField = "CityName";
                   
                this.ddlCities.DataBind();
            }
        }
    }
}

SQL Here second row CityName is NULL

Screenshot