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StatusThe thesis was presented on the 11 October, 2018Approved by NCAA on the 25 January, 2019 Abstract![]() ThesisCZU 633.15:631.52
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The thesis is exposed on 122 pages with 42 tables, 7 figures and contains introduction, six chapters, general conclusions and recommendations, bibliography of 195 sources and 2 annexes. The research results are published in 26 scientific papers.
Research domain. Plant breeding and seed production.
Research goal. Increasing efficiency in the process of developing maize hybrids by replacing parental forms and modification of seed parents based on related crosses and backcrosses. Objectives. Comparative evaluation of quantitative characters and attributes on inbred lines, related crosses and backcrosses, using of related crosses as initial material for improving of commercial lines. Highlighting the criteria for selecting seed parents in the synthesis process of single cross and single modified hybrids, identification of performance hybrid combinations for promotion in official state testing.
Scientific novelty and originality. For the first time, parental forms were estimated by genetic affinity, combining ability, seed tolerance at suboptimal temperatures, and grain size fractionation. Single crosses and single modified hybrids with related and backcrossed seed parents were appreciated by the variability of essential morphological traits.
The solved scientific problem consists in substantiating and improving the methodology for the selection of parental forms of single cross and modified single cross early maize hybrids, which led to the more efficient use of crosses between the inbred lines with 30-60% of genetic relationship and the concretization of the sphere of usage of backcrosses in parental forms, which allow and ensures to profitable production of certified seed. Theoretical significance. The estimated correlation between valuable agronomic traits of inbred lines, modified seed parents and testcrosses allow prognostication with a higher level the probability of performance in hybrids.
Applicative value. For official testing were submitted 8 single crosses and 3 single modified hybrids, of which two have been registered in Moldova (Porumbeni 310 and in Romania) and Bemo 203, Bemo 235, Porumbeni 220 and Porumbeni 243 in R. Belarus.
Implementation of scientific results. The commercial seed production of registered hybrids Bemo 203, Bemo 235 and Porumbeni 310 in the years 2016-2017 was carried out on a 770 hectare area in different agriculture units by “Forever” LTD.