S02 - Session P5 - Natural variation of fruit quality traits within a tomato core-collection

Authors: Stanislava Grozeva *, Ivanka Tringovska, Veneta Stoeva, Daniela Ganeva, Amol Nankar, Dimitrina Kostova

Fruit quality is associated with several internal and external fruit attributes that are important to satisfy the requirements of the consumers. The aim of this study was the evaluation of a tomato core collection for valuable fruit quality traits. It comprised 189 accessions, including landraces, old varieties, modern breeding lines, and wild relatives. The collection was assessed in a field experiment for two years (2019 and 2020). Fruit quality traits, such as colour, firmness, weight, soluble solids content (SSC), vitamin C, total polyphenols (TP) and antioxidant activity (AA), were evaluated in mature fruits. The main elements of external quality attributes were the fruit colour and firmness. As a result, the genotypes were classified into seven colour groups (green, yellow, orange, red, pink, brown and others) based on CIELab parameters and calculated colour indexes (chroma and hue). Several genotypes were identified with better colour characteristics. The highest variation for fruit firmness (5.8-42.6 shore) was observed in the accessions with very small fruits. The SSC and vitamin C values decreased from very small (SSC 12.0 o Brix and vitamin C 33.4 mg/100g FW) to very big-fruited accessions (SSC 3.9 o Brix and Vitamin C 22.8 mg/100g FW) accessions. Similar changes were observed for TP and AA, for which the highest values were observed in very small-fruited accessions. Accessions with outstanding levels of traits were identified and included in a future breeding program.