Three-dimensional characterization of hazelnut (Corylus avellana L.) fruit development based on X-ray micro-computed tomography.

Hazelnut (Corylus avellana L.) is one of the most appreciated and cultivated nuts in temperate areas. Producers are now facing an increasing demand and industries need to select high-yielding and fine-quality cultivars. In this context, a challenge to take up is the development of a rapid, non-destructive and high-resolution method to study the growth and differentiation dynamics of floral reproductive organs, to limit yield losses especially in response to climate adaptation. In this study, we scanned mixed buds from the hazelnut cultivar Tonda di Giffoni from anthesis to fruit formation by micro-computed tomography (Micro-CT). We reconstructed in three dimensions (3D) the spatial arrangement of flowers within the glomerulus, characterized the position and configuration of ovules, ovaries and funiculus as well as observed the formation of the embryo during the early developmental stages. The proposed approach enables precise volume measurements of ovaries, ovules, and embryos. It helps identify abortive ovules early and track developmental stages, such as embryo formation. Unlike traditional 2D methods, this approach captures growth patterns more accurately, supporting research on fruit development, crop quality, and genetic studies. Overall, it provides a powerful tool for advancing reproductive biology research of hazelnuts and improving hazelnut cultivation.