Assessment of the Genetic Structure and Diversity of Orobanche cumana populations from Turkey Using Simple Sequence Repeat Markers

Abstract

Orobanche cumana Wallr. known as sunflower broomrape is a holoparasitic plant that causes huge yield losses in sunflower (Helianthus annuus L.) fields. Genetic characterization, genetic diversity, and race determination studies in O. cumana are very significant for preventing threats in sunflower fields. In this study, the broomrape populations sampled from Edirne, Kırklareli, Tekirdağ, and Adana provinces were used for genetic characterization. The sensitive Özdemirbey sunflower variety was used for growing O. cumana individuals. Eight simple sequence repeat (SSR) loci (Ocum52, Ocum70, Ocum81, Ocum87, Ocum108, Ocum141, Ocum160, and Ocum196) were used for the evaluation of genetic characterization and diversity of broomrape populations. All studied SSR loci were found to be polymorphic and yielded a total of 22 alleles in 143 samples analyzed. Na = 2.089 (mean number of alleles per locus), Ne = 1.390 (mean effective alleles), I = 0.392 (mean Shannon’s information index), Ho = 0.156 (mean observed heterozygosity), He = 0.239 (mean expected heterozygosity), and PIC = 0.228 (mean polymorphic information content) were calculated to assess genetic diversity of O. cumana populations.. As a result of molecular variance analysis, it was concluded that found that the genetic diversity of the populations was 38% among the population. The remaining 23% and 39% were due to among individuals and within individuals, respectively. The UPGMA method and STRUCTURE analysis divided the studied populations into 2 groups. Cluster I included LK2013, HT2016, T2018, and LE2013 populations, while group 2 included AE2003, AD2018, and MT2013 populations. The results we obtained have enabled us to reach important genetic diversity information about O. cumana, and the information obtained will provide important contributions for planned studies in the future.