The dissertation is devoted to solving the important scientific task of establishing peculiarities of manifesting soybean valuable economic characteristics by determining selection value of collection samples and choosing valuable initial material for selection. The screening of the collection samples according to valuable economic characteristics enabled to place the samples for specific selection program and create a new hybrid material. The collection samples Lehenda (UKR), Biliavka (UKR), Bilosnizhka (UKR), LF-8 (POL) having the duration of growing season up to 90 days were chosen. The results of three year research showed that the maximum number of pods per plant was formed on Hejiao – 87-94-3 (CHN). Kyvin (UKR) and L-101 line (MDA) formed the largest number of seeds per plant. Concerning thousand seed weight, the samples were divided into three groups. Only one soybean sample Hejiao 87-94-3 (CHN) was characterized by a high thousand seed weight. Collections of soybean samples for a complex of valuable economic features are selected.
Plastic and stable samples concerning the duration of growing period and seed weight per plant were chosen for using in the process of adaptive selection. Changeability level of valuable economic traits was established and the correlation coefficients between these traits in soybean collection samples were determined.
It has been established that such characteristics as “the amount of branches per plant” (29,9 %), “the amount of pods per plant” (22,9 %), “seed weight per plant” (22,8 %), “the amount of productive joints” (20,4 %) have a high level of variability. “The height of lower pod attachment” (17,1 %), “the amount of seeds in a pod” (16,8 %), “the amount of seeds per plant” (16,4 %), “growing season duration” (14,3 %), “plant height” (13,4 %), “thousand seed weight” (11,1 %) have average level of variability. “Stem thickness” (8,1 %) is characterized by a low degree of variability.
The manifestation of correlation dependencies showed itself as stable during the study years. The weight of seeds per plant was closely connected with thousand seed weight (r = 0,95), the amount of pods per plant (r = 0,93), the amount of productive joints per plant (r = 0,91), amount of seeds per plant (r = 0,79).
According to the results of cluster analysis the collection material was distributed within five clusters. Variety samples in the cluster were similar concerning the correlation of quantitative signs but had different genetic origins. The most productive samples were concentrated in the second and fifth clusters. Samples belonging to different clusters were involved in hybridization as parent forms. The parent forms were in four clusters out of five ones.
The character of inheriting the duration of growing period and seed productivity signs in F1 and F2 soybean hybrids were researched. Based on the results of studying characteristics of variability and inheritance in F1 and F2 hybrids, the breeding value of combinations of crossing was established.
It was revealed that inheriting by heterosis type is expressed in seed weight per plant, number of pods and seeds in the vast majority of F1 hybrids. The nature of inheriting growing season duration is different from the type of inheriting the main characteristics of seed productivity, in most cases intermediate inheritance is observed.
Based on the established selection and genetic regularities, a valuable initial material was created in accordance with elevated seed productivity characteristics. Hybrid combinations of Zlata (RUS) / Adamos (UKR), OAC Vision (CAN) / Adamos (UKR), OAC Vision (CAN) / Almaz (UKR), LF-8 (POL) / Almaz (UKR), LF-8 (POL) / Kyvin (UKR) were chosen with high positive rate and degree of transgressions in F2.
The samples, chosen according to valuable economic characteristics, and selected F2 hybrids are used in scientific-research institutions of Ukraine.
