how to handle full submit with html beginform and ajax beginform

In my code, i use ajax.beginform for collection entries (with modal window for new entries) then refresh the list.

Controller

public ActionResult BusinessCategoryNewUpdateRow(BusinessCategoryViewModel vmodel)
    {
        try
        {
            vmodel.Subcategories.Add(vmodel.NewEditEntry);
            return PartialView("BusinessCategory/SubBusinessCategoryView", vmodel);
        }
        catch
        {
            return View();
        }
    }

View : 

@using (Ajax.BeginForm("BusinessCategoryNewUpdateRow", "BusinessReference", new AjaxOptions
        { UpdateTargetId = "subCategoryPart", OnSuccess = "clearDialog" }, new { id = "showWin" }))
        {
            

                

                    

                        

                            @Html.LabelFor(model => model.MainCategory.name, new { @class = "floating-label" })
                            @Html.EditorFor(model => model.MainCategory.name, new { htmlAttributes = new { @class = "form-control" } })
                            @Html.ValidationMessageFor(model => model.MainCategory.name, "", new { @class = "text-danger" })
                        
                    
                
                

                    

                        

                            @Html.LabelFor(model => model.MainCategory.business_cat_code, new { @class = "floating-label" })
                            @Html.EditorFor(model => model.MainCategory.business_cat_code, new { htmlAttributes = new { @class = "form-control" } })
                            @Html.ValidationMessageFor(model => model.MainCategory.business_cat_code, "", new { @class = "text-danger" })
                        
                    
                
                

                    

                        

                            @Html.LabelFor(model => model.MainCategory.description, new { @class = "floating-label" })
                            @Html.EditorFor(model => model.MainCategory.description, "Text", new { htmlAttributes = new { @class = "form-control" } })
                            @Html.ValidationMessageFor(model => model.MainCategory.description, "", new { @class = "text-danger" })
                        
                    
                

                

                    

                        
Sub-Category
                    
                    

                        @*Add*@
                        Add
                    
                

                @*popup window*@
                

                    

                        

                            

                                
Add/Edit Subcategory
                                ×
                            
                            

                                

                                    

                                        

                                            @Html.LabelFor(model => model.NewEditEntry.name, new { @class = "floating-label" })
                                            @Html.EditorFor(model => model.NewEditEntry.name, new { htmlAttributes = new { @class = "form-control" } })
                                            @Html.ValidationMessageFor(model => model.NewEditEntry.name, "", new { @class = "text-danger" })
                                        
                                    
                                
                                

                                    

                                        

                                            @Html.LabelFor(model => model.NewEditEntry.business_cat_code, new { @class = "floating-label" })
                                            @Html.EditorFor(model => model.NewEditEntry.business_cat_code, new { htmlAttributes = new { @class = "form-control" } })
                                            @Html.ValidationMessageFor(model => model.NewEditEntry.business_cat_code, "", new { @class = "text-danger" })
                                        
                                    
                                
                                

                                    

                                        

                                            @Html.LabelFor(model => model.NewEditEntry.description, new { @class = "floating-label" })
                                            @Html.EditorFor(model => model.NewEditEntry.description, "Text", new { htmlAttributes = new { @class = "form-control" } })
                                            @Html.ValidationMessageFor(model => model.NewEditEntry.description, "", new { @class = "text-danger" })
                                        
                                    
                                
                            
                            

                                Save
                                Close
                            
                        
                    
                
                @*popup window*@
                

                    

                        

                            

                                @Html.Partial("BusinessCategory/SubBusinessCategoryView", Model)
                            
                        
                    
                
            
        }

This part is ok, the problem is when i include/add Html.BeginForm outside Ajax.BeginForm, the add button of modal window triggers the Html.BeginForm instead of the Ajax.BeginForm.

What is the best approach to handle collections (parent-child entries) then perform a final submit using Html.BeginForm and Ajax.BeginForm? 
Is there a similar code snippet to cater parent-child entries?