Molecular Cloning and Sequence Analysis of the its Region of Nuclear Ribosomal DNA for Species Identification in Dodders (Cuscuta; Convolvulaceae)

Dodder (Cuscuta sp.) is an obligate parasitic plant that is very difficult to control. In plants the internal transcribed spacer (ITS) region of the 18S-5.8S-26S nuclear ribosomal DNA (nrDNA) has been considered one of the most important sequences for phylogenetic analysis. Here we report the analysis of nrDNA's ITS sequences as an efficient tool to study the phylogeny of dodders collected from various provinces of Eastern Anatolia (Turkey). Genomic DNA of six dodder samples belonging to 4 distinct species was extracted from body tissue samples. The sequences of 18S rRNA, ITS-1, 5.8S rRNA, ITS-2 and 26S rRNA regions of 4 Cuscuta species were determined by molecular cloning and sequencing. The identity of cloned fragments was compared to determine sequence identity using NCBI database. Bootstrap analysis of nrDNA of C. approximate, C. lupuliformis, C. campestris and C. babylonica indicated high sequence identity with similar sequences belonging to different geographical origins of the world retrieved from NCBI database. Our results clearly showed that the most stable secondary structure derived from the sequences obtained by universal ITS4 and ITS5 primers is very efficient tool for identification of Cuscuta species when used in combination with phylogenetic analysis. (C) 2017 Friends Science Publishers