Inheritance of the Average Weight of the Fruit in Tomato Hybrids with High Lycopene Content

: We studied five parental forms of tomato (Solanum Lycopersicum L. ). Were obtained twenty F 1 hybrids by the complete diallel scheme (5×5) and used to study inheritance of the average weight of the fruit. Were used as parental forms in the system of diallel crosses according to Hayman V. I. and Jinks I. J.: the line №477 (sp, u) , variety Alya (sp) and three collection samples with high lycopene content in fruits: Dark green (hp -2 dg ), MO 112 (hp) and T-3627 (B c ) . The results of the evaluation are given of the general and specific combining ability of the five parental forms of tomato of the average weight of the fruit, established the character of inheritance. In the course of research it was found that the average weight of the fruit is controlled by the additive-dominant genetic system. Inheritance occurs by type of incomplete dominance. The main role in the genetic control of the trait is played by the additive effects of genes, which allows for selection, starting with the second hybrid generation. The direction of dominance varies from the dominance of genes that reduce the manifestation of the trait to its absence. The highest reliable effects of general combining ability (GCA) had the variety Alya, which must be used to create heterosis hybrids. From hybrid combinations with his participation in the future it is possible to make selections for creation of varieties.


Introduction
Tomato is one of the most nutritious vegetable crops in the world [1]. Modern medicine recommends tomato fruit as a therapeutic and dietary agent that increases the body's immune system, lowers cholesterol, prevents the development of diabetes and Alzheimer's disease. Carotenoids contained in tomatoes have anticancer properties [2][3][4][5]. All these qualities make tomato fruit an important component of the daily diet.
Recently, there has been an increase in demand for tomato fruit consumption, both fresh and processed, which creates considerable space for the development of breeding to improve productivity and fruit quality [7]. Important indicators of productivity that are taken into account when selecting parental forms for breeding programs are the number of fruits per plant and the average weight of the fruit [8].
Highly pigmented forms with mutant genes hp-2 dg , B og , B c are a valuable material in the breeding for fruit quality, however, their characteristics are low productivity, late and extended ripening period, which significantly reduces the practical value [9][10][11][12]. Selection and involvement in crossing of early and high-yielding forms of a tomato allows to rececive a qualitative initial material which can be used in the further work for creation of heterosis hybrids and varieties [13][14].
To create a source material with a set of desirable economically valuable features, it is necessary to use a 70 Liudmila Andreevna Rudas et al.: Inheritance of the Average Weight of the Fruit in Tomato Hybrids with High Lycopene Content breeding material with a high general or specific combining ability. The best assessment of combining ability can be obtained by dialysis analysis [15][16][17]. It is also used to quickly obtain data on the nature of the inheritance of quantitative traits that are controlled by groups of genes (polygens) [18].

Materials and Methods
The purpose of this research is to identify parental forms with high general and specific combining ability and genetic analysis to establish genetic parameters and the character of inheritance of the average weight of the fruit.
The research was conducted in 2017˗2019 in the fields of breeding and seed crop rotation of Cherkassy research station of the National Scientific Center «Institute of Agriculture of the National Academy of Agrarian Sciences of Ukraine», located in the village Kholodnyansky (49 0 11'N at 31 0 52'E) Cherkassy region, Ukraine. For genetic analysis by (Hayman B. I., 1954;Jinks I. L., 1954) were used the line №477 (sp, u) and the variety Alya (sp) with a reduced period of fruit ripening and three collection samples with high lycopene content in fruits: Dark green (hp 2dg ), МО 112 (hp) and Т˗3627 (B c ).
The experiments are based on the method of one˗factor experiments [19]. Evaluation of the combining ability of the average weight of the fruit was performed according to the first scheme Griffing B. I. with the matrix of crosses and test p2 (direct and reciprocal crosses + parental forms), where p ˗ is the number of parental forms [15]. Genetic analysis was performed by Hayman V. I. and I. J. Jinks [17,20].

Results and Discussion
Were found by analysis of variance in a one-factor experiment significant differences between hybrids. The average weight of the fruit is different, and the studied samples and varieties can be expected to differ in combining ability (general or specific) ( Table 1). The sum of squares in hybrids is due to genotypic differences. Parental line, variety and samples differed in the magnitude of the expression of the trait ( Table 2). The largest weight of the fruit was the variety Alya (88.0-133.1 g), the lowest value of the trait was in the samples The results of the analysis of variance of the combining ability (Table 3) indicate significant differences in general and specific combining ability. In addition, for two years of research (in 2018 and 2019) was found a significant reciprocal effect. Studies have shown that the average weight of the fruit for the best reliable effects of general combining ability (GCA) for three years of research had a variety of Alya (from 11.69 to 18.11) ( Table 4). Significant negative values of the effects of general combining ability (GCA) during the three years of research (from minus 2.09 to minus 8.58) and (from minus 1.28 to minus 5.67), respectively, had samples Dark green and №477. Samples MO 112 and T-3627 had significant negative values of the effects of GCA for two years of research.
Significant differences in specific combining ability (SCA) over the years of research indicate that some hybrid combinations within the variety differed significantly from its average value, and non-additive effects of genes are involved in the inheritance of the trait. In order to identify samples and varieties with high or low specific combining ability (SCA), for each parent form, we calculated the variance for comparison with the overall average value ( Table 5).
We found that high reliable values of specific combining ability (SCA) for three years of research were in the sample №477   For three years of research was established the predominance of non-additive effects of genes in the sample №477 and for two years -in the sample T-3627. Thus, it was found that in most cases in genetic control traits are dominated by additive effects of genes, which makes it possible to make selections starting from the second hybrid generation. The variety Alya with high general combining ability (GCA) effects should be used to create heterosis hybrids. From the above-mentioned hybrid combinations with its participation in the future it is possible to make selections for creation of varieties.
Genetic analysis by ( High Lycopene Content that the inheritance of the average weight of the fruit, involved additive and non˗additive effects of genes (the regression coefficients are reliable and do not differ from one), that is, the regression line does not deviate from the unit slope line. This is confirmed by the high significance of the components D and H1, which characterize the variability of the trait, which is due to the additive and dominant effects of genes (Table 6). The uneven ratio of genes with positive and negative effects is indicated by the ratio of H2 /4H1, which was 0.17-   High correlation coefficients between covariance (Wr) and variance (Vr), as well as regression coefficients b 1 between Wr and Vr (Table 8) indicate that the actual regression lines do not differ significantly from the unit slope.   In 2017, according to the F 1 assessment, the samples МО 112 and Т-3627 approached the point with the maximum dominance. Samples Dark green and №477, which had 75 percent recessive alleles, approached the point with the highest recessiveness. The point of the variety Alya is located in the middle of the regression line.
In 2018, the placement of varieties and samples on the regression chart changed. Samples МО 112 and T-3627, which had 100 percent dominant alleles, were located in the zone with the highest dominance. Points of variety Alya and sample T-3627 were located in the zone of greatest recessiveness and had, respectively, 50 and 75% of recessive alleles. The point of the sample Dark green was located in the middle region of the regression line.
In 2019, the points of the four parental forms were located in the zone of greatest dominance: samples №477, Dark green, MO 112 and T-3627. The point of the variety Alya lies in the middle region of the regression line, far from the points of intersection of the parabola with the regression line.

Conclusions
Genetic analysis to establish that of the average weight of the fruit is controlled by the additive-dominant genetic system. The main role in the genetic control of the trait is had by the additive effects of genes, which allows the selection of the phenotype, starting with the second hybrid generation. Inheritance occurs by type of incomplete dominance. The direction of dominance varies from the dominance of genes that reduce the manifestation of the trait to its absence.
Studies have shown that of the average weight of the fruit the best reliable effects of general combining ability (GCA) for three years of research had a variety Alya (from 11.69 to 18.11). It can be recommended for the creation of heterosis hybrids and varieties. From hybrid combinations with the participation of the variety Alya, we conducted selections for the creation of varieties.