Evaluation of Sicilian landraces of broccoli (B. oleracea var. italica Plenck) for quality traits

Brassica oleracea L. var. italica Plenck is one of the most popular vegetables which belong to Brassicaceae family. It is getting attention as an important source of bioactive compounds such as glucosinolates, and many other phytochemicals. In the frame of the H2020 BRESOV project, we evaluated three landraces (‘Broccolo nero’, ‘Ramoso calabrese’ and ‘Sparaceddu’) and two commercial F1 hybrid cultivars (‘Marathon’ and ‘Naxos’). The seedlings were transplanted in Mojo-Alcantara (Sicily) in November 2020 (4 plant m-2) to monitor plant phenological stages and biometric, sensorial, and biochemical traits of the produce. Plants were characterized through bio morphometric parameters using the following descriptors: stem and basal diameter, grain size, colour, soluble solid content; sensorial analysis by panel test was performed using fresh inflorescence appearance and leaves portions. Biochemical analysis of glucosinolates (GLSs) amount and their profile were carried out using freeze-dried samples of the evaluated accession. The results showed significant differences, among genotypes, in plant habitus, sprouting/branching and flowering time. The most performing genotype in term of inflorescence weight was ‘Naxos’ (415.6 g), followed by ‘Marathon’ (112.7 g). The Sicilian landraces ‘Broccolo nero’ and ‘Sparaceddu’ showed lower curd diameter (35.6 and 21.5 mm, respectively) than commercial F1 hybrids ‘Marathon’ and ‘Naxos’ (84.3 and 151.3 mm, respectively). Concerning soluble solid content, it was high in ‘Sparaceddu’ (8.53 °Brix), ‘Naxos’ F1(8.30 °Brix) and ‘Broccolo nero’ (8.14 °Brix), while it was low in ‘Marathon’ F1 (6.12 °Brix). The ANOVA results of the sensory data showed significant differences (p≤0.05) in the attributes colour intensity and overall. Among the Sicilian landraces, the accession ‘Sparaceddu’ had the highest content of total GLSs (20.21 µmol dw-1), and its profile was very articulated in comparison to the hybrid F1 ‘Naxos’.