Breeders' Sensory Test: A new tool for early selection in breeding for tomato (Solanum lycopersicum) flavour

Abstract

For several decades, improved flavour has not been a main focus in tomato breeding because it is difficult and expensive to evaluate. Sensory panels are designed to assess flavour, but they are not able to evaluate large sample numbers typical for early breeding generations. Selection in the first segregating generation could enhance breeding for flavour by preventing the loss of favourable alleles. The efficiency of early selection is unknown due to the polygenetic inheritance of flavour. To address these issues, F2 plants from 32 crosses and their parents (910 individuals) were evaluated for aroma, sweetness and sourness with the Breeders' Sensory Test (small team and large number of small samples from individuals), as well as for physicochemical traits (total soluble solids, titratable acidity and dry matter), and volatile compounds in low‐input organic and hydroponic cultivation. Corresponding physicochemical and sensory traits were significantly correlated. For most of the studied traits, it was possible to select between single plants in the F2 generation. Thus, the Breeders' Sensory Test can be used as a new tool in breeding for flavour.

Flavor and Other Quality Traits of Tomato Cultivars Bred for Diverse Production Systems as Revealed in Organic Low-Input Management

“…Despite their obvious advantages regarding number of cultivars and, more importantly, the time required for analysis, field evaluations are generally subjective and prone to error because they are usually based on the sensory preferences of one or few individuals ( 39 ). However, Hagenguth et al ( 36 ) demonstrated a highly significant correlation of sweetness and TSS and sourness and TA, indicating the efficiency of the breeders’ sensory test. A trained panel may not able to assess a large number of samples in a short time, which is typical for early breeding generations, for example, that also require replications ( 36 ).…”

“…However, Hagenguth et al ( 36 ) demonstrated a highly significant correlation of sweetness and TSS and sourness and TA, indicating the efficiency of the breeders’ sensory test. A trained panel may not able to assess a large number of samples in a short time, which is typical for early breeding generations, for example, that also require replications ( 36 ).…”

“…Due to the high number of cultivars in 2015, a sensory evaluation, using the breeders’ sensory test ( 36 ) was carried out. Three panelists (male, 25–50 years of age) with experience in sensory evaluation of tomatoes, knowledge of the cultivars to be evaluated, and the terminology to be used were trained in preparation for the sensory evaluation.…”

“…Sensory attributes that contribute to the fruit flavor (fruit firmness, juiciness, skin firmness, sweetness, sourness, aroma), and the acceptability were assessed. The scoring was based on a 9-point scale (0 = minimum intensity and 9 = maximum intensity), with the detailed description of the assessed attributes, following Hagenguth et al ( 36 ) for most of the attributes. Fruit firmness referred to resistance of the pericarp during first chewing, and skin firmness referred to the degree to which the epidermis remained intact during chewing.…”

“…The technical procedure for panel training and sensory evaluation sessions was the same as the protocol of sensory methods described in Daoud et al (24) with modifications. The sensory attributes used in this panel test were similar to those used in the breeders' sensory test (36). The panelists were trained in eight sessions during 2-week training prior to the evaluation.…”