Consolidated BBCH scale for hazelnut phenotyping

European hazelnut cultivars are grouped by comparing their phenological development to a few reference cultivars such as ‘Barcelona’, ‘Tonda di Giffoni’ and ‘Tonda Gentile delle Langhe’. The cultivars are described as earlier or later than the references for blooming, and harvest time.
BBCH scales describe the plant phenological stages according to a numerical scale.
The conversion of alphanumerical codes to a fully numerical code would allow easier phenological computer data analysis.
While the scale is widely used in predictive agriculture, it needs to be updated for hazelnut cultivation considering current knowledge.
The aim of this study was to present a consolidated BBCH scale for European hazelnut phenotyping.
The plant phenology was divided into eight growth stages, from bud development to senescence as follows: stage 0, bud development; stage 1, leaf development; stage 3, stem elongation; stage 5, male inflorescence emergence; stage 6, male and female flowering; stage 7, fruit development; stage 8, fruit ripening; and stage 9, dormancy or winter rest.
The eight growth stages were subdivided into 53 specific sub-stages corresponding to each specific phenophase of the hazelnut growing season.
This updated scale is easily usable once the translation between historical and BBCH scales are grasped by the observer.
The phenological stages of hazelnut can be described from the male inflorescence development (stage 5) in one year until fruit ripening (stage 8), which occurs in the next year.

X International Congress on Hazelnut

J. Toillon, R. Hamidi, A. Paradinas, L. Ramade, M. Thomas, E. Suarez Huerta

Corylus avellana L., filbert, phenology monitoring, flowering, leaf bud flush, climate change, leaf budbreak

https://doi.org/10.17660/ActaHortic.2023.1379.23