Genetic diversity and population structure of modern Bulgarian tomato: Insights from molecular and biochemical data
Elena G. Todorovska
, Nikolai K. Christov, Stefan V. Tsonev, Daniela G. Ganeva
, Stanislava Y. Grozeva
, Ivanka I. Tringovska
, Nasya B. Tomlekova
Abstract: Genetic variation in eight modern Bulgarian tomato varieties and advanced breeding lines showing morphological and biochemical differences was assessed using 182 simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers in 19 genes involved in diverse metabolic pathways associated with quality and other agronomic traits. The genetic diversity within the collection based on SSRs was relatively low (0.368) but similar to that observed with SNP markers (0.316), with a mean genetic diversity estimated from both marker types of 0.3670. Nei's genetic distance based on both marker types varied from 0.1973 between Plovdivska karotina and L21β to 0.7788 between IZK Alya and L984. The grouping in the cluster analysis and the inferred population structure reflected to some extent the morphological and biochemical characteristics of the studied tomato genotypes. The most diverse genotypes are IZK Alya and lines 1140 and 1116. The observed grouping of Plovdivska karotina and L21β in a common sub-cluster of the UPGMA dendrogram reflects their similar morphological and biochemical composition, especially of β-carotene content, which is an important antioxidant that may prevent some chronic diseases, like various cancers and cardiovascular diseases. The genetic distance information for the studied collection could be useful for implementation of further tomato breeding strategies towards improvement of nutritious and yield related traits as well for human diet, farmers and processing industry in Bulgaria.
Keywords: biochemical parameters; genetic diversity; genotyping; molecular markers: SSR (Simple sequence repeats); population structure; SNP (Single nucleotide polymorphism); tomato (S. lycopersicum L.)
Citation: Todorovska, E. G., Christov, N. K., Tsonev, S. V., Ganeva, D. G., Grozeva, S. Y., Tringovska, I. I. & Tomlekova, N. B. (2026). Genetic diversity and population structure of modern Bulgarian tomato: Insights from molecular and biochemical data. Bulg. J. Agric. Sci., 32(3), 652–666
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| Date published: 2026-06-25
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