Veselyi V. Selection within lines for productivity in maternal forms' breeding of hybrid sunflower

Object: degree of manifestation, stability, variation of productive traits in lines-maintainer of sunflower sterility and efficacy of their improvement for breeding value by intra-line selection. Aim: to establish the peculiarities for the variation of productive traits in lines-maintainers of sunflower sterility and efficacy of their improvement by intra-line selection. Methods: field, laboratory, mathematic-statistic. Novelty: for the first time an important scientific task dealt with the increase of productivity in selfed lines of sunflower by intra-line selection is generalized and solved; the efficacy of such a selection by the traits of productivity in lines-maintainers of sterility is established; with this method sublines having improved indices for productivity, thousand seed weight, seed number per head are identified; correlations important for resultative intra-line selection by productive traits are revealed with intra-line selection some lines are improved and identified for combining ability, on their basis heterotic hybrids are created. Results: efficacy of the improvement of lines-maintainers of sunflower sterility is proved on the basis of the established peculiarities of intra-line selection traits' relationships, their variation and manifestation of combining ability. 17 sublines with the improved indices of certain of productivity, 6 of these have an improved combining ability for grain yield, have been chosen. 7 valuable maternal forms are found, 7 hybrids with these have revealed a high competitive heterosis for grain yield and listed in the State Plant Variety Register suitable for dissemination in Ukraine. Application stage: 7 hybrids, bred on the base of identified original lines with high combining ability have been registered in State Plant Variety List, suitable for dissemination in Ukraine: Oskil, Yason sine 2007, Bogun, Boyets and Forvard since 2008, Ryuryk and Romans since 2009. The identified sublines have been included into research programs of Plant Production Institute nd. a. V. Ya. Yuriev of NAAS, Oil Crop Institute of NAAS, Selection-genetical institute of NAAS, Southern biotechnological centre in plant breeding of NAAS. Application area: breeding institutions.