Search

Purpose. Due to changing climatic conditions and the spread of new viral diseases, an important issue in beet growing is the expansion of plasma ulture using new sterile cytoplasm from wild species of the genus Beta L. as an alternative to Owen’s S-cytoplasm. The goal of this work was to obtain new breeding genotypes based on new cytoplasm. Methods. Cytological, biotechnological. field and laboratory. Results. Availability of recombination in the locus of grafted genes of one-year and two-year development cycles B+b- and hypocotyl colour R+r- was determined using the method of analytical crosses. Earlier we have proved the positive effect of sterility maintainer Beta vulgaris Nxxzz in replacement of the sterility maintainer genome based on our results on the selection of hypocotyl of green color r-rand two-year development cycle b-b- in the interspecific hybrids F2 obtained under the hybridization scheme Beta maritima L: ♀B1C maritima / ♂ Beta vulgaris Nxxzz (Роїк М. В., 2013). In the case of interspecific hybrids, in the conditions of sterile cytoplasm Beta patula L., only backcross offspring of the third cycle of saturating crosses were identified by one- and two-year developmental cycles. Seed bearing plants of BC3S patula of a two-year development cycle were characterized by spreading stems, multi-seeded fruits (3, 4 seeds) and sterile anthers. At the same time, monogermity and a two-year development cycle were restored against the background of sterile cytoplasm of Beta patula L. only among the seed bearing plants of the fourth cycle of saturating crosses. Recombinant genotypes with a red hypocotyl colour and a two-year development cycle BC4S patula R+r- were characterized by multigermity, chimericalness by sterility of CMS‑1 and CMS‑0 type and single- and multi-stem morphological types of anthers. The expression of CMS nuclear genes in the newly replaced BC5S patula lines was marked by high sterility rates of the CMS‑0 type; however, the fertility rates required additional rejection of multigerm seed plants. This is an indicator of the complex structure of the fertility locus in wild Beta patula L. and the special response of the nuclear genome of the sterility maintainers to the new cytoplasmic background. Experimental triploid hybrids with the new introductory sterile cytoplasm Beta patula L. were determined by high sugar content and dry matter content up to 29%. Conclusions. Alloplasmic lines based on the cytoplasm of the wild species Beta patula L are created. Their sugar content at the level of experimental triploid hybrids was 19.5% and 20.5% with a dry matter content of 25% —29%. Alloplasmic lines with a new BCC Beta patula L. recommended for use in the selection process of sugar beets.

Purpose. Revealing the effect of the cytoplasmic genome of replaced lines with the plasma of wild species Beta patula and B. maritima L., and apozygotic lines A4–A8 with the cytoplasm of S vulgaris Owen on the main factors of apozygotic reproduction, seed productivity, germination, monogermity and sterility as affected by the genetic origin of breeding material. Methods. The research was carried out in the Cytogenetics Laboratory (IBCSB), the Laboratory for Apomixis and Polyploidy of the Yaltushkiv EBS, and the Laboratory for Adaptive Breeding (Veselyi Podil EBS). Apozygotic seeds were obtained under a pollen-free regime according to the IBCSB’s Methods for Spatial Isolation and Parchment Insulators. Each seed bearer plant phenotype was determined during the flowering period by pollen sterility and partial flowering. Classification of plants was performed according to Owen (1945), with identifying plants of CMS-0, Type CMS-1, and CMS-2 types. The Monogermity of seed plants was assessed visually by the presence of separate fruits on the central shoots. In 2021, the roots of the replaced lines of the Veselyi Podil EBS were planted under the conditions of a pollen-free regime in the experimental field of the IBCSB. Seed production under apozygositic conditions was studied, taking into account the number of set fruits per 10-cm segment with 5 replications for each seed bearer. Germination was determined on the 10th day and germination vigour on the 5th day. Results. New sources of cytoplasmic male sterility (CMS) were obtained in the cytogenetics laboratory based on a genetic model of crossbreeding analysis, using differentiation and tools according to the marker-linked genes of hypocotyl color R+r-, and one / two-year development cycle B+b-. The analyzers for the nature of sugar beet sterility were sterility maintainers, dominant homozygotes for recessive genes of anthocyanin color, development cycle, partial fertility and sterility (NBeta vulgaris Sxxzz rr bb). Monogerm pollen-sterile lines with an apomictic way of seed reproduction (Yaltushkiv EBS) (A4–A8 Beta vulgaris Sxxzz rr), selected for the dominant color of the hypocotyl R+r-, stabilized for the trait of monogermity, 100% sterility and 2x gene ploidy, were characterized by low seed productivity. High rates of apozygotic seed development (80 to 96.4% of the number of set flowers) were observed against the background of the sterile cytoplasm of Beta maritima (Turkey). In the CMS BC4S patula line, the number of set apozygotic seeds ranges from 34 ± 0.3 to 39 ± 0.42, and the indicators of degenerated flowers under apozygotic regime varied from 31.2 to 54.3%. Isolated were seed plants with high self-reproduction, such as BC4S maritima Turkey, k.2/1, k.6/2, k.6/3 and k.3/4, k.9/4 on the background of new plasma of wild species of B. patula. The phenomenon of high self-reproduction of seeds (up to 98.5−96.4% of set flowers) was detected in line 21-011 CHS BC5S patula, which was comparable with hybrids and sterility maintainers (97.5−93.1%), which is determined by a special interaction of the beet nuclear genome of sugar beet and new plasma of wild species of the genus Beta L. Conclusions. The apomictic way of seed reproduction ensures the shortening of the breeding scheme for sugar beet due to high seed reproduction of mother parent in substituted lines with new plasma and differentiation by gametophytic reduction of parthenogenesis using morphological marker traits.

Purpose. Find out the features of biometric indicators formation in sugar beet hybrids of domestic breeding. Methods. Field, laboratory. Results. According to the results of the research, it was determined that in early August, the maximum weight of roots (840 g) was in hybrid ‘ITsB 0904’. Good indicators were observed in hybrids ‘Umanskyi Ch S97’, ‘Soniachnyi’ and ‘Anichka’, 770, 780, and 800 g at the average group indicator of 730 g. It was investigated that the hybrid ‘Maksym’ (15.1%) and ‘Etiud’ (14.9%) were the best in terms of sugar accumulation in roots. Sugar content at the level of 14.8 % was observed in hybrids ‘Umanskyi ChS 97’, ‘Ramzes’, ‘Konstanta’, ‘Soniachnyi’ and ‘Verkhnia’ at the average group value of 14.5%. Conclusions. It is important to continue the study of the dynamics of root and leaf mass formation together with the process of sugar accumulation in roots in terms of establishing individual efficiency of hybrids and developing recommendations for the fullest realization of their potential in production conditions.