Sets the color of marker that is displayed on legend. This property works only with Pie and Doughnut charts. Value of legendMarkerColor can be “HTML Color Name” or “hex” code.
Default: dataSeries marker colorvar  chart =  new  CanvasJS.Chart("container",
{
 .
 .
  data:[ {
   dataPoints: [
    {x: 10 , y: 50 , legendText: "Apple", legendMarkerColor: "green"},
  ],
  },
 ]
 .
 .
});
chart.render();
Also See: