Diversity of Ppd-1 genotypes of spring and winter bread wheat (Triticum aestivum L.) of Ukraine

Abstract

Ancient and modern 183 varieties of winter and 23 spring types of development of bread wheat (Triticum aestivum L.) selected Ukrainian state institutions and private companies are characterized by alleles of Ppd-D1, Ppd-B1, and Ppd-A1 genes. Allele-specific molecular markers, proposed in the scientific literature, were used to identify carriers of the Ppd-D1a, Ppd-D1b, Ppd-D1c, Ppd-D1d, Ppd-B1a, Ppd-B1c, Ppd-A1b alleles. According to the results of PCR analysis, the most widespread among the studied winter cultivars was observed in the dominant allele Ppd-D1a (91.9 %) with a range from 80.0 % in the sampling of varieties of the Northeast (Kharkiv, Sumy) to 95.0 % in southern cultivars (Odesa, Kherson), and in spring – recessive Ppd-D1c (43.5 %). The share of carriers of various recessive alleles of the Ppd-D1 gene among spring varieties is 73.9 %, and among winter – 8.1 % and, except for Borovitsa and Talisman consists of cultivars created by the late 60 – early 70 years of last century. The frequencies of the Ppd-B1a and Ppd-B1c alleles are quite small. The Ppd-B1a allele was found only in three spring varieties, and the Ppd-B1c allele in 5 winter varieties and spring wheat Struna Mironivska, except for the latter cultivar, in all cases found together with the Ppd-D1a allele. The Ppd-A1 gene was present in a recessive state in all studied sorts. Seven different homozygous Ppd-1 genotypes have been determined in the studied cultivars. Samples of winter and spring varieties differ significantly in the quantity and frequency of specific Ppd-1 genotypes. The presence of varieties with monogenic dominant Ppd-D1a or Ppd-B1c control of traits and digenic dominant Ppd-D1a Ppd-B1a genotypes has been marked in spring wheat, as well as monogenic dominant for Ppd-D1a and digenic dominant for Ppd-D1a in winter wheat varieties. In spring cultivars the share of carriers of recessive alleles of Ppd-1 genes is several times higher (69.6 %) than in winter varieties; conversely, the samples of winter varieties have significantly more dominant alleles (91.9 %). Such differences in genotype frequencies are due to the timing of sowing and duration of the natural day at the latitude of the growing region during the growing season of winter and spring varieties.