Hi shrutipatra,

You can change the marker style of your ScatterLine chart in C# by setting the MarkerType on your series to Custom, and then setting the Marker.Style property to the custom style you created.  Here's an example of what I did:

Here's my custom Marker in my UserControl resources:

<Style TargetType="igChart:MarkerPointTemplate" x:Name="MarkerStyle">

       <Setter Property="Template">

         <Setter.Value>

             <ControlTemplate TargetType="igChart:MarkerPointTemplate">

                   <Path Fill="Green" Stretch="Fill" Stroke="Magenta" Data="M157,234 L172.5,190.5 182.5,232.5 147.5,207.5 193.5,205.5 z"/>

     </ControlTemplate>

      </Setter.Value>

   </Setter>

</Style>     

Here is the code I perform on a button click to set my ScatterLine series marker to my custom marker:

 private void btnSetMarkerStyle_Click(object sender, RoutedEventArgs e)
        {
            Marker m = new Marker();
            m.Type = MarkerType.Custom;
            this.Chart1.Series[0].Marker = m;
            this.Chart1.Series[0].Marker.Style = this.Resources["MarkerStyle"] as Style;
        }

Hope this helps!

-Marisa