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The objective of this study was to establish classification ranges for genetic and additive genetic coefficients of variation, as well as for broad and narrow sense heritability, as a function of growth and wood quality traits for Eucalyptus spp. We conducted statistical analyses to determine differences in this classification the types of coefficients used. The selected studies that met the inclusion criteria, 58 presented genetic variation coefficients (448 data points) and 53 presented heritability coefficients (423 data points). To descriptive statistics and the Shapiro-Wilk test, we confirmed that it was necessary to separate coefficients and traits into groups. Inconsistencies for growth traits were observed, confirming the influence of experimental error, indirect estimation methods, and environmental effects on coefficient estimates. We recommend the use of the classification tables included in this literature review to interpret results in studies so as to standardize the classification of coefficients of genetic variation and heritability. [ABSTRACT FROM AUTHOR]

To accelerate the production of oil flax forms with improved indicators, it is necessary to know the nature of the genetic interaction in hybrid populations, in particular, the heritability of quantitative traits of seed productivity. Effective selection of plants is possible with a simultaneous combination of two conditions: wide phenotypic variability of the population and high heritability of the trait. For selection, genotypic variability is important, which is determined using the coefficient of heritability (H). The use of this genetic-statistical parameter makes it possible to speed up and optimize the breeding process by selecting genotypes with a new, more favorable combination of valuable traits and rejecting low-value material at the first stages of breeding. The aim of the study is to identify interspecific and intraspecific hybrid combinations with high rates of heritability, promising for the selection of plants with a large number of bolls. The research was carried out at the Institute of Oilseed Crops NAAS in 2019-2020. The material of the study was interspecies and intraspecies hybrids of oilseed flax of the second generation obtained in the system of dialle crosses of three samples of cultivated flax (L5, L6, M32/2) and two wild species (L. angustifolium, L. hispanicum). The second generation hybrids were studied in the F2 hybrid nursery in blocks according to the scheme: maternal form -- forward and reverse F2 hybrid -- parental form. Boll structure analysis was performed on 150 F2 hybrid plants and 20 parental plants. The coefficient of heritability (H) was determined by the formula (Ayala 1984) and subdivided according to the gradation (Ala 1976) into: high -- 0,66-1,0; medium -- 0,33-0,65; low -- 0,00-0,32. As a result of researches it is established that at interspecies and intraspecies hybrids of the second generation the sign «number of bolls on the plant» was inherited in average and high degree (H = 0,48-0,90, 0,52-0,87 accordingly). Highlighted promising hybrid combinations with a high heritability of the number of bolls, which can be used to predict the efficiency of plant selection in early generations (F2-F3). The most valuable for selection are hybrid combinations, in which high rates of heritability rates are noted for two years of research: interspecific L. angustifolium x M32/2 -- 0,79-0,83, M32/2 x L. angustifolium -- 0,76-0,80, M32/2 x L. hispanicum -- 0,82-0,90; intraspecific L5 x M32/2 -- 0,71-0,81, M32/2 x L6 -- 0,80-0,87. [ABSTRACT FROM AUTHOR]

The creation of a selection material for oil flax with a large number of stems, side shoots and an optimal height for cultivation is an urgent task, since the formation of additional bolls on the side shoots will increase the yield of seeds, and an increase in the vegetative mass of plants will increase its competitiveness against weeds and reduce moisture evaporation. from the soil surface. The use of genetic and statistical parameters allows to efficiently plan and carry out breeding work for oil flax, purposefully select parental pairs in crosses, select valuable genotypes, and reject low-value material at the first stages of breeding. The purpose of this study is to identify promising interspecific hybrid combinations based on breeding and genetic parameters for creating a new breeding material for multi-stem and multi-shoot forms. The studies were carried out at the Institute of Oilseeds NAАS of Ukraine in 2018-2020. The material of the research was F1 and F2 hybrids obtained in a system of dialle crosses with the participation of two wild species (L. angustifolium and L. hispanicum) and three samples of cultivated flax – L 6 (India), M 32/2 (Ukraine), L 5 (Czech Republic). The degree of dominance of traits in hybrids of the first generation was determined by the formula (Beil, Atkins 1965). The degree of heterosis is according to the formula (Rasul et al 2002). The coefficient of heritability in hybrids of the second generation – according to the formula (Ayala 1984). As a result of the research, interspecific hybrid combinations have been identified that are promising for obtaining breeding material with a modified habit: – with the effect of heterosis: by plant height – seven combinations of F1 (Ht = 3,58-13,76%); the number of stems per plant – one (Ht = 35,77%); the number of side shoots is six (Ht = 5,68-43,79%). The most valuable are combinations in which the effect of heterosis manifested itself simultaneously on two grounds – the height of the plants and the number of lateral shoots on the plant – L. angustifolium / L 6, L 5 / L. angustifolium, L. hispanicum / L 6, L 6 / L. hispanicum; plant height and number of stems per plant – M 32/2 / L. hispanicum; – with high coefficients of heritability: by plant height – four combinations of F2 (H = 0,67-0,87); the number of stems per plant – six (H = 0,66-0,81); the number of side shoots is four (H = 0,66-0,72). Interspecific combinations of L. hispanicum / M 32/2 and M 32/2 / L. hispanicum were distinguished by high rates of heritability by two characteristics – the number of stems and the number of lateral shoots on the plant. The potential of the selected combinations will be used in the further breeding process for increased branching. [ABSTRACT FROM AUTHOR]

The research was aimed at examining variability, variance components, broadsense heritability (h2), expected genetic advance of thousand grain weight (TGW) and grain number per spike (GNS) of 15 genotypes of bread wheat and 15 genotypes of durum wheat. Field trials were carried out during 2010-2011 and 2011-2012 growing seasons at the three sites: Rimski Šančevi, Zemun Polje and Padinska Skela. Results of this investigation showed that the genetic component of variance (σ2 g) was predominant for TGW of bread and durum wheat and for GNS of bread wheat. The genotype × environment interaction (σ2 ge) component of phenotypic variance was 8.72 times higher than σ2 g for GNS of durum wheat and pointed to the greater instability of durum wheat genotypes. h2 was very high (>90%) for TGW and GNS of bread wheat, high for TGW of durum wheat - 87.3% and low for GNS of durum wheat - 39.5%. Considering the high values obtained for h2 - 96.4% and the highest value for expected genetic advance as percent of mean (GAM) - 19.3% for TGW of bread wheat, the success of selection for desired values of this yield component can be anticipated. The success of selection cannot be predicted for GNS of durum wheat due to low values obtained for h2 and GAM of 39.5% and 2.8%, respectively.

The genotypic parameters study of the selection traits makes to determine methods for their improvement possible. The economic significance, heritability and correlation of cows weight, calves weaning weight, first calving age and the calves safety at the first calving cows Ukrainian Beef cattle breed were determined. The study was conducted in a cows array (n = 316) including 89 motherdaughter pairs. It is determined that a decrease in the age of the first calving will lead to a deterioration in the calves weaning weight (r = 0.184) and a decrease cows weight (r = 0.221). The analysis of genetic correlations showed that daughters of late first calving age cows, have a larger weight (r = 0.492) and lesser weaning weight calves (r = -0.150) and a calves survival during suckling period (r = -0.215). Selection of heifers from cows with high calves weaning weight, has positive influence all the selection traits, except for the survival of suckling calves. The economic weight coefficients of cows traits were determined at their influence for the lifelong calves weaning weight on the basis of one day their life. The first calving age has the most important economic importance in the herd of Ukrainian Beef cattle. The cows weight have the lowest coefficient of economic value. [ABSTRACT FROM AUTHOR]

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In the 1994/95 season, 1272 accesses of the Active Maize Germplasm Bank (CENARGEN-EMBRAPA) were evaluated in several locations previously chosen to assure incidence of leaf diseases caused by Phaeosphaeria maydis and Exserohilum turcicum. Two composite populations named RPM (Resistant to P. maydis) and RET (Resistant to E. turcicum) were synthesized after recombination of 46 and 34 accesses, respectively. After two generations of recombination, a sample of 300 open pollinated ears (half-sib families) was chosen from each population. Families were evaluated in Anhembi (SP) in the 1999/00 season in six experiments with 50 families representing each population. The hybrid Master (Novartis Seeds) was used as check. The additive genetic variance ( 2 A ) and the coefficient of heritability ( 2 F h ) were estimated for ear yield, plant height and ear height. Mean yield of the RPM composite was 5.707 t ha-1 (77% of the hybrid check). Plant and ear height means were 19.4% and 36.3% higher than check. Parameters of variability were high with estimates of 2 A and 2 F h of 554.73 (g/pl)2 and 0.58, respectively. Mean yield of the RET composite was 4.393 t ha-1 (56.7% of the hybrid check). For plant and ear height, means were slightly lower than check. In the RET composite the variability for yield was less expressive with estimates of 195.58 (g/pl)2 and 0.40 respectively.