DOES JEWISH LAW PERMIT GRAFTING MELON OR WATERMELON ON PUMPKIN?

According to Jewish law, it is forbidden to graft two different kinds of plants. Melon and watermelon are rather remote from pumpkin. All three have wide variability in fruit morphology, but each genus can produce fruits that appear similar to those produced by the other two genera. This has lead to their identification as a single kind in folk taxonomy. As they are considered by Jewish folk taxonomy as one kind, it is suggested that the prohibition of grafting does not apply to them.