Study of rare species of wheat as donors for breeding for functional nutrition

Common wheat (Triticum aestivum L.), which accumulates anthocyanins in grain, is a promising raw material for the production of functional nutrition products. When creating anthocyanin-rich varieties of grain crops, the choice of suitable donors is important. In this work, for the first time, using a comprehensive analysis of anthocyanin pigmentation patterns of vegetative organs and grain in rare wheat species from the collection of the Vavilov All-Russian Institute of Plant Genetic Resources (VIR), donors of dominant alleles of the Ba , Pp-1 , and Pp3 genes that control anthocyanin synthesis were identified, and their resistance to fungal diseases was assessed. The aim of the work was to study rare wheat species for the presence of anthocyanin pigmentation of grain and vegetative organs, identify donors of dominant alleles of the Ba , Pp-1 and Pp3 genes, and evaluate potential donors for resistance to fungal diseases. Manifestations of anthocyanin coloration of grain and vegetative organs were studied in 16 rare wheat species from the VIR collection: einkorn T. urartu Thum. ex Gandil (n = 68), T. boeoticum Boiss. (n = 99), T. monococcum L. (n = 113); emmer T. dicoccoides (Körn. ex Aschers. et Graebn.) Schweinf. (n = 256), T. dicoccum (Schrank) Schuebl. (n = 502), T. araraticum Jakubz. (n = 42), T. timopheevii Zhuk. (n = 45); naked tetraploids T. aethiopicum Jakubz. (n = 246), T. persicum Vav. (n = 140), T. polonicum L. (n = 61), T. turanicum Jakubz. (n = 38), T. turgidum L. (n = 421); spelt T. spelta L. (n = 231), T. macha Dekapr. et Menabde ( n = 37); naked hexaploids T. compactum Host. ( n = 616), T. sphaerococcum Perciv. ( n = 54). A total of 2969 samples were analyzed. The presence of anthocyanin pigmentation of the coleoptile was assessed in 5-7-day-old seedlings germinated on Petri dishes at room temperature and natural light. The color of the leaf sheath, culm node, and leaf blade auricles was assessed at the Dagestan Experimental Station of VIR (41.98° N, 48.33° E) in 2019-2021. The color of the leaf sheath was determined in the interphase period of tube elongation-earing, the color of the sheaths was assessed in the three lower leaves, the color of the auricles and stem nodes was noted in the earing phase, examining at least 10 plants. For DNA genotyping, 65 accessions were selected from the studied wheat collection, including 22 T. boeoticum accessions (17 accessions with blue and 5 accessions with red grain coloration), 3 T. durum accessions (with purple, white, and red grain coloration), 8 T. spelta accessions (2 accessions with blue, 3 with white, and 3 with red grain coloration), and 32 T. aethiopicum accessions (23 accessions with purple, 1 with white, and 8 with red grain coloration). DNA was isolated from young leaves of five plants of each accession. The isolated DNA was analyzed by PCR using the intragenic markers Pp3-diagnostic and ThMyc4E-specific, developed for the anthocyanin biosynthesis genes Pp3 and Ba1 , respectively. Phenological observations and assessment of the resistance of samples to fungal diseases against a natural infectious background were carried out at the Dagestan Experimental Station of VIR in 2017-2018. Resistance was assessed on a 9-point scale. The collection included 13 and 2 blue-grained samples of T. boeoticum and T. spelta , respectively, carrying dominant alleles of the Ba genes controlling the synthesis of anthocyanins in the aleurone layer of the grain, and 22 purple-grained samples of T. aethiopicum carrying dominant alleles of the Pp3 gene, which, together with the Pp-1 genes, controls the synthesis of anthocyanins in the pericarp of the grain. The presence of dominant alleles of the Ba and Pp3 genes in the genome of the identified accessions was confirmed using DNA genotyping with molecular markers. In addition, all T. timopheevii and most T. turanicum accessions were white-grained, which implies the presence of mutations in the genes controlling the synthesis of proanthocyanidins. Analysis of the color of vegetative organs showed that different wheat species are characterized by different pigmentation patterns, which implies, in addition to the known Pp-1 genes controlling the color of vegetative organs, the involvement of additional genes in the formation of the color of different parts of the plant. In most of the analyzed species, the color of the coleoptile often manifested itself together with the color of the leaf sheaths and auricles, with the exception of T. timopheevii and T. araraticum , which had color of the coleoptile and auricles, but no color of the leaf sheaths. The pigmentation of stem nodes often did not depend on the presence of anthocyanin pigment on other vegetative organs and, apparently, is inherited independently.