Can find single input box and disable it. unable to do for full tr.What is wrong?

Question

var element = "";
                     var aval_qty = "";
                    $.each(data.response.available_stk, function (a,b){
                        aval_qty = '.a'+b.id_itm;
                        $(aval_qty).each(function(i, obj) {
                            //alert(b.qtys)
                             $(this).children().eq(0).val(b.qtys);
// alert(b.qtys)
                             if(b.qtys ==0)
                             {

                                //elements.parent().parent().('input[type="text"], input[type="checkbox"], select').prop("disabled", true);
                                element.parent().find('.serialno').prop('disabled',true);
                             //$(this).parent().find('#recqantity').removeClass('errorClass');;

                            // $(this).parent().find('.serialno').multiselect('rebuild');errorClass
                             }
                             else
                             {
                                // $(this).parent().find('input[type=text]').prop('disabled',false);
                            // $(this).parent().find('.serialno').prop('disabled',false);
                             }
                        });
                    }); 

if(b.qtys ==0) i need to find that particular tr and need to disable all input types .i can find single input box and disable it. unable to do full tr.