PRODUCT CHARACTERISTICS OF TRITICUM PETROPAVLOVSKYI AND ITS SPONTANEOUS MACROMUTANTS

The studies were conducted on the experimental field of the FSBSI “Federal Russian Agricultural Research Center”, whose soils are ordinary blackearth (chernozem). 25 productive shoots of each sample were taken in their full ripeness, and, when the seeds reached standard humidity, there was performed a structural analysis in the laboratory. T. petropavlovskyi and spontaneous macromutant forms emerged from cultivation were used as the objects of study. In the process of a long-term cultivation of T. petropavlovskyi in the collection, there were identified numerous spontaneous macromutant forms of a specific nature. The paper presents the study results of the product characteristics of T.petropavlovskyi and spontaneous macromutant forms which are phenotypically close to T. spelta and soft-like T. aestivum and typical soft wheat T. aestivum. It has been established that product characteristics of speltoid macromutant wheat are significantly inferior to the original T. petropavlovskyi and macromutant soft wheat T. aestivum. Product features of soft-like macromutant T. aestivum is similar to the original T. petropavlovskyi, but has a smaller sprout weight and, correspondingly, lower grain productivity. The most promising variety for breeding process is the macromutant typical soft wheat T. aestivum, which forms a larger number of grains and, due to this, has an advantage in ‘kernel weight per head’ over all samples, including the initial form. The value of this macromutant form can also be determined by the high coefficient of specific productivity (Csp), which indicates a more efficient work of its vegetative organs. Consequently, the macromutant T. aestivum, which is phenomenally similar to the existing varieties of soft wheat, promises a high hybridization efficiency with the latter. Thus, the macromutant form of T. aestivum, developed on the basis of the T. petropavlovskyi genotype, is of some value as an initial material for breeding practice.

Possible origin of Triticum petropavlovskyi based on cytological analyses of crosses between T. petropavlovskyi and tetraploid, hexaploid, and synthetic hexaploid (SHW-DPW) wheat accessions

Intraspecific hybridization between Triticum petropavlovskyi Udacz. et Migusch., synthetic hexaploid wheat (SHW-DPW), and tetraploid and hexaploid wheat, was performed to collect data on seed set, fertility of F1 hybrid, and meiotic pairing configuration, aiming to evaluate the possible origin of T. petropavlovskyi. Our data showed that (1) seed set of crosses T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum cv. Chinese Spring was significantly high; (2) fertility of hybrids T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum ssp. yunnanense was higher than that of the other hybrids; (3) fertility of F1 hybrids SHW-DPW × T. dicoccoides and SHW-DPW×T. aestivum ssp. tibetanum was significantly high; and (4) c-value of T. petropavlovskyi × T. polonicum and T. petropavlovskyi × T. aestivum cv. Changning white wheat was also significantly high. The results indicate that the probable origin of T. petropavlovskyi is divergence from a natural cross between T. aestivum and T. polonicum, via either spontaneous introgression or breeding effort.