Development of a uniform phenology scale (BBCH) in hazelnuts

Abstract

Several methods are used to monitor phenological events in crop plants, and the BBCH scale ("Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie") is a widely used one. However, a BBCH scale does not exist for hazelnut. In this manuscript, we used the BBCH monograph for mono- and dicotyledonous and woody plants to propose a BBCH scale for hazelnut. We list the standardized plant development stages and show the equivalent descriptors in the UPOV and Bioversity International (IPGRI) lists and the development stages published in France and Italy. The proposed monograph covers eight of the ten principal BBCH stages, starting with dormant buds (stage 0) and ending with harvested nuts (stage 9).