Sustainable hazelnut production: improving yield and quality with microbial inoculant

Corylus avellana is a globally cultivated shrub, with Turkey and Italy as top producers. One of the most appreciated Italian cultivars is “Tonda Gentile Trilobata” whose fruits have a well-shaped kernel and typical sensory characteristics like sweetness and aroma. Recently, due to the growing demand of hazelnuts, new strategies aiming at increasing the yield and green cultivation techniques have been proposed. In this context, biostimulants can offer a sustainable approach to improve not only productivity, but also plant health and fruit nutritional value. This study explores the use of beneficial soil microorganisms to improve plant growth, productivity and fruit quality of C. avellana over three years of cultivation. Plants were inoculated with arbuscular mycorrhizal fungi (AMF) and/or with Pseudomonas protegens Pf7. Morphometric parameters, hazelnut production and quality were assessed. Results showed that inoculated hazelnut plants started production in advance and increased productivity. Even hazelnut sizes and quality were affected by inoculation. Fatty acid analysis highlighted differences in the proportion of oleic and linoleic acids in hazelnuts from plants inoculated and cultivated with specific microbial combinations. This study demonstrated for the first time that C. avellana growth and fruit quality can be improved by AMF and soil bacteria.