Evaluation of Fruit Shape Variations in Spanish Eggplants using an Image Analysis Software

Traditional descriptors for characterization of fruit shape of eggplant (Solanum melongena L.) provide limited information and do not allow a detailed characterization of this complex trait. New image analysis software tools like Tomato Analyzer, allow obtaining quantitative and objective data for a large number of fruit shape parameters. The Tomato Analyzer software tool was used for the evaluation of fruit shape in a collection of traditional varieties of eggplant from four varietal groups (Round, Semi-long, Egg Shaped, and Long). A total of 26 fruit shape parameters were obtained using the Tomato Analyzer software. Significant differences were found among varieties for all traits, except for shoulder height. In addition, considerable differences were identified among varietal groups for many parameters. Values for broad-sense heritability were high for most of the traits. The principal components analysis clearly separated the four varietal groups. Discriminant analysis allowed the correct classification to their actual variety of almost 60 % of the individual fruits. The wide variation observed and high values for heritability for most fruit shape parameters indicated that the image analysis software tools like Tomato Analyzer are of great utility for the phenotypic characterization of fruit shape in eggplant germplasm. This has important implications for selection and breeding for this important trait in eggplant.