S03 - Session O2 - New tools for organic plant nutrition: microbial and aminoacid treatments for organic seed production of broccoli (Brassica oleracea var. italica plenk.)

Authors: Simone Treccarichi *, Riccardo Cali, Donata Arena, Giulio Flavio Rizzo , Davide Felis, Ferdinando Branca

The amount and the quality of the organic seeds are the limiting factor for organic farming systems. One of the objectives of the H2020 BRESOV project (Breeding for Resilient, Efficient, Sustainable and Organic production) is to improve the quality of seeds for both phytosanitary and productive traits. In this frame, the effect of new plant nutrition tools based on microorganisms and organic nitrogen on the quantity and quality of broccoli seeds production was evaluated. We compared a set of 8 broccoli varieties including 2 commercial hybrids F1 (Marathon and Gentleman) and 6 Sicilian landraces (Ciuriettu aprilino, Broccolo nero, Cavolo broccolo ramoso calabrese, Sparaceddu, Settembrino, Sanmartinaro) with three different nutrition protocols (NP) based on 3KO © ( Trichoderma Arzianum , T. Asperellum and T. Atroviride ), Amminocomplex extra © (based on organic nitrogen), Stim root © (nitrogen, iron, zinc and carbon) and Kappa micro © (boron, iron, manganese, molybdenum and zinc). Plants were characterized for phenological stages with Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie scale (BBCH), bio-morphometric traits, such as stem and basal diameter, plant height and weight, presence of secondary branches and color of flowers through the International Board for Plant Genetic Resources ( IBPGR) descriptors. Number of branches, number of siliqua in the first branch, seed yield per plant, number of seeds per siliqua, 1000 seed weight were also calculated as yield components. We ascertained significant differences for seed yield and quality (germinability, mean germination time, coefficient of uniformity) in relation to the NPs and the genotypes analysed. The genotypes showed significant differences for inflorescence appearance, plant size and presence of secundary branches. The Sicilian landraces, Sparaceddu and Broccolo nero were the most performing landraces both for seed yield and quality than the commercial hybrids F1 Marathon and Gentleman.