Complete Chloroplast DNA Sequences of Zanduri Wheat

Georgia plays an important role in wheat formation. In the past, the Zanduri population of Georgia was a set of diploid – Triticum monococcum var. hornemanii (2n =14) (Gvatsa Zanduri), tetraploid Triticum timopheevi (2n=28) (Chelta Zanduri) and hexaploid Triticum zhukovskyi Men. et Er. (2n = 42). It is a Zanduri puzzle that wild T.timopheevi (T.araraticum) was not found in Georgia, though cultivated T.timopheeviwas only detected here.

Next-generation sequencing  technologies enable the determination of complete nucleotide sequences of both chloroplast and mitochondrial DNA of many higher plants, including wheat. The genetic structure of Zanduri wheat is more accurately inferred by the complete sequences of chloroplast DNA. In the present investigation, the complete sequences of three Zanduri wheats  and wild T.araraticum are presented. Sequencing of chloroplast DNA was performed on an Illumina MiSeq platform. Chloroplast DNA molecules were assembled using the SOAPdenovo computer program.

The sequenced chloroplast DNA molecules were compared to other Triticum and Aegilops species, and a phylogenetic tree was constructed. T.araraticum, T.timopheevi and T.zhukovskyi  chloroplast DNA showed the closest phylogenetic relationship with the chloroplast DNA of Ae.speltoides. The most significant difference was in the 114-bp deletion within the gene ndhH in the Timopheevi species. Unlike T.araraticum, T.timopheevi and T.zhukovskyi have a 6-bp repeat in the gene ndhH, which results in a dipeptide duplication in the corresponding protein.

Gvatsa Zanduri chloroplast DNA slightly differs from other einkorn chloroplast DNA. In comparison to T.monococcum var.monococcum, four SNPs can be identified, two in gene matK and one in gene ndhD.