**Analysis of Wheat Bread-Making Gene (***wbm***) Evolution and Occurrence in Triticale Collection Reveal Origin via Interspecific Introgression into Chromosome 7AL**

**Ilya Kirov 1,\*, Andrey Pirsikov 1, Natalia Milyukova 1, Maxim Dudnikov 1, Maxim Kolenkov 1, Ivan Gruzdev 1, Stanislav Siksin 1, Ludmila Khrustaleva 2, Gennady Karlov 1,2 and Alexander Soloviev 1**


Received: 11 November 2019; Accepted: 4 December 2019; Published: 5 December 2019

**Abstract:** Bread-making quality is a crucial trait for wheat and triticale breeding. Several genes significantly influence these characteristics, including glutenin genes and the wheat bread-making (*wbm*) gene. World wheat collection screening showed that only a few percent of cultivars carry the valuable *wbm* variant, providing a useful source for wheat breeding. In contrast, no such analysis has been performed for triticale (wheat (AABB genome) × rye (RR) amphidiploid) collections. Despite the importance of the *wbm* gene, information about its origin and genomic organization is lacking. Here, using modern genomic resources available for wheat and its relatives, as well as PCR screening, we aimed to examine the evolution of the *wbm* gene and its appearance in the triticale genotype collection. Bioinformatics analysis revealed that the wheat Chinese Spring genome does not have the *wbm* gene but instead possesses the orthologous gene, called *wbm-like* located on chromosome 7A. The analysis of upstream and downstream regions revealed the insertion of LINE1 (Long Interspersed Nuclear Elements) retrotransposons and Mutator DNA transposon in close vicinity to *wbm-like*. Comparative analysis of the *wbm-like* region in wheat genotypes and closely related species showed low similarity between the *wbm* locus and other sequences, suggesting that *wbm* originated via introgression from unknown species. PCR markers were developed to distinguish *wbm* and *wbm-like* sequences, and triticale collection was screened resulting in the detection of three genotypes carrying *wbm*-specific introgression, providing a useful source for triticale breeding programs.

**Keywords:** triticale; wheat bread-making gene; introgression; PCR markers
