New tools for organic farming: amino acids and Trichoderma spp. application improved snap bean (Phaseolus vulgaris L.) seed yield and quality

The amount and the quality of organic seeds are limiting factors in organic farming systems. One of the objectives of the H2020 BRESOV project (Breeding for Resilient, Efficient, Sustainable and Organic production) was to improve the quality of seeds from both phytosanitary and productive point of view. In this context, the effect of amino acids and mycorrhizal fungi (Trichoderma arzianum, T. asperellum and T. atroviride) based treatments designed for organic agriculture were evaluated on snap bean (Phaseolus vulgaris L.) seed production. A set of 7 snap bean genotypes was evaluated under three different nutrition protocols (NP): NP0 (only background fertilization), NP100 (application of amino acids and PGPM based treatments) and NP100F (NP100 with additional treatment based on microelements and biostimulants applied by foliar nutrition). The plantlets were transplanted in Comiso (Sicily) in March 2022 (crop density of 20 plants m-2), adapting a split-plot experimental design with the main plot represented by the nutrition protocol and the sup-plot represented by the genotype. The pods for seed production were collected at the maturity stage. Significant differences in seed yield and quality due to the adapted nutrition protocol were observed. The interaction among the experimental factors also influenced the parameters analyzed. In particular, higher seed production and germinability were recorded when amino acids and PGPM were applied by fertigation.