Morphological, technological and molecular characterization of some sugar beet (Beta vulgaris L.) varieties and populations

Sugar beet is one of the important sources of sucrose grown in many regions of the world. This study was conducted in 2022 and 2023 to determine the genetic diversity between genotypes by performing the morphological, technological and molecular characterization of 96 sugar beet varieties and populations. The study was carried out in the application field of Muş Alparslan University, Department of Plant Production Technologies, in accordance with the Augmented trial design. In the molecular part of the study, 10 SCoT (Start Targeted Codon) primers were used to determine the level of genetic relationship between sugar beet genotypes. According to the data obtained as a result of molecular studies, the polymorphism rate between sugar beet genotypes was found to be 97,60%. Of the 265 DNA bands formed, only 6 were monomorphic and the remaining 259 were polymorphic. In the study, polymorphism information content value (PIC), one of the genetic diversity parameters, varied between 0.180 (SCoT15) and 0.300 (SCoT16) and the average was recorded as 0.239. The average effective allele number (Ne) was found to be 1.36, genetic diversity index (h) was 0.22, Shannon's information index (I) was 0.33, and total genetic diversity value (ht) was 0.21. It was determined that the primer that gave the most information about the genetic diversity parameters determined with the help of SCoT markers was SCoT3, and the primer that gave the least information was SCoT21. The average genetic distance of 96 sugar beet genotypes was calculated as 0.522, and the highest genetic distance value was found to be between Germany-10 and Iran-10 genotypes, with 0.773. In the study, 26 phenotypic features were examined in terms of morphology and technology, and it was determined that there were significant variations among sugar beet genotypes in this respect. As a result of the analysis of phenotypic characters, genotypes Iran-22 and Iran-11 of Iran origin showed promising properties in terms of root yield and root weight. In terms of polar sugar content and dry matter content, the Denmark-1 genotype of Denmark origin had higher values than the other genotypes. As a result of the study, it was determined that genotypes of Iranian and Turkish origin had superior values in terms of root yield, while genotypes of European origin stood out in terms of dry matter ratio and polar sugar ratio, and these results were supported by UPGMA and Structure analyzes in molecular studies. A significant genetic diversity has been detected among sugar beet genotypes, both in phenotypic characteristics and in genetic parameters determined with the help of molecular markers. The aim of this study is to select genetic material with the desired characteristics for future studies, to determine superior hybrid combinations and to pave the way for the development of high quality varieties. Keywords: Sugar beet, Genetic diversity, SCoT markers, morphological characterization