Identification of the ploidy level of triticale (×Triticosecale Wittmack) regenerant plants obtained by the anther culture method

Haploidy is widely used in plant breeding to accelerate the development of new varieties, reducing the time required to create homozygous lines by an average of 5–7 years. The in vitro anther culture method is the most effective for the production of haploid triticale plants. Along with haploids, regenerated plants obtained by this method may be spontaneous diploids. Therefore, determining the level of ploidy is an important part of the technology for obtaining doubled haploids (DH lines). The aim of the research is to study the possibility of using stomatal cell parameters to evaluate the ploidy level of regenerants obtained in triticale (×Triticosecale Wittmack) anther culture. It has been established that stomatal cell parameters correlate with the number of chromosomes in regenerants and can be used to screen ploidy levels on a large scale. Based on the studied indicators, plants with the same ploidy level were found to be sufficiently homogeneous. This allows us to conclude that genotype has an insignificant effect on this indicator within the studied samples. No significant differences were observed between spontaneous diploids from anther culture and controls (triticale plants obtained from seeds). The length of stomatal cells was found to be 61.6 ± 0.8 μm for haploid plants and 86.6 ± 0.4 μm for spontaneous diploids. The cell density per 1 mm² is 31.2 ± 0.3 pcs and 20.2 ± 0.4 pcs, for haploids and diploids, respectively. Of the forty plants studied, seven turned out to be spontaneous diploids, exhibiting a chromosome doubling frequency of 17.5%. The indirect determination of the ploidy level of regenerants was confirmed by a direct cytogenetic method of counting the number of chromosomes in regenerant plant root tips. A strong statistically significant negative correlation was found between stomatal cell length and density per unit area (r = 0.96**); i.e., the relationship between these two indicators is nearly functional.