Phenological growth stages of “pawpaw” [Asimina triloba (L.) Dunal, Annonaceae] according to the BBCH scale

Abstract

The “pawpaw” [Asimina triloba (L.) Dunal] is a deciduous fruit tree native to eastern North America where it is produced at a limited commercial scale. It is particularly interesting due to its tropical flavor and powerful aroma, unique features for a fruit crop adapted to temperate climates. Although the “pawpaw” is still an underutilized fruit crop, it has a clear niche for expansion in regions with temperate climates. However, appropriate phenological comparisons in different regions are hampered due to the lack of a standardized phenological coding system in this species. Thus, in order to fill this gap, in this work, we describe with detail the phenological growth stages of the “pawpaw” by using a two-digit decimal coding system, according to the extended BBCH-scale (Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie). The BBCH code allows to easily identify the standard phenological stages under field conditions, a useful tool for management of fruit crops and essential for the expansion of “pawpaw” to other growing areas.