Handle the PrepareViewStyleInfo event, and then set e.Style.BackColor depending upon the value of e.RowIndex.
Private Sub GridDataBoundGrid1_PrepareViewStyleInfo(ByVal sender As Object, ByVal e As Syncfusion.Windows.Forms.Grid.GridPrepareViewStyleInfoEventArgs) Handles GridDataBoundGrid1.PrepareViewStyleInfo
If e.RowIndex mod 2 = 1 Then
e.Style.BackColor = Color.Blue
End If
End Sub