International Code of Nomenclature for algae, fungi, and plants
Breeding programs have created cultivars that are the products of further hybridizing "P." ×"bretschneideri" with "P. pyrifolia". Under the International Code of Nomenclature for algae, fungi, and plants, such backcross hybrids are named within the species "P." ×"bretschneideri". Cultivar 'PremP109', also called 'Prem 109', is such a hybrid, marketed under the trademark Papple.