Make changes on Trigger for good work

Make change on 1 line on trigger for survey 4.
Isn't newItem already a Farmer_Product_Delivery object?

If so, you should just be adding the fields the newItem directly.

newItem.Number_of_Baskets__c = fao.Number_of_baskets__c;
newItem.Delivery_Date__c = fao.Delivery_Date__c;
etc ...

and then the trigger will take care of saving it. You don't even have to worry about saving anything...