## 3 Results  
In the situations considered, the number of traits on the basis of which Mahalanobis distances of parental forms were calculated ranged from nine to nineteen. The number of markers on the basis of which genetic similarity/diversity was calculated ranged from 145 to 1703. Analyzing all 1980 sets of observations, statistically significant correlations were observed between genetic diversity and heterosis effects (\(-0.071\)) and Mahalanobis distances and SCA effects (\(0.049\)) (Table 1). The correlation coefficients had small absolute values despite statistical significance (Figure 1). In addition, an intriguing result is the negative (\(-0.071\)) dependence of the heterosis effect on genetic diversity. The relationship between diversity of parental forms and breeding parameters may have been influenced by the fact that all cumulative effects--positive and negative, significant and insignificant--were included. Let us consider only statistically significant heterosis effects. As before, and in this case, there was no significant effect of phenotypic variation and genetic variation of the parental forms on the heterosis effect values of their hybrids (Figure 2, Table 2). \begin{table}
\begin{tabular}{c c c} \hline
**Parameter** & **Phenotypic Distance** & **Genetic Distance** \\ \hline Heterosis effect & 0.041 (0.074) & \(-0.071\) (0.002) \\ SCA effect & 0.049 (0.029) & 0.012 (0.584) \\ \hline \end{tabular}
\end{table} 
Table 1: Pearson linear correlation coefficients and \(p\)-values (in brackets) between phenotypic distances (Mahalanobis) and genetic distances and heterosis and SCA effects calculated from all 1980 datasets. Figure 1: Relationships between variation in parental forms (phenotypic and genotypic) and values of breeding parameters (heterosis effect and SCA effect) obtained from all 1980 sets of observations. The yellow line denotes the trend line. Figure 2: Relationships between variation in parental forms (phenotypic and genotypic) and heterosis effect values obtained, for cases where heterosis effects were statistically significant. The yellow line denotes the trend line. Phenotypic variation in parental forms did not affect the positive effects of heterosis (Figure 3), while it statistically significantly (\(r\) = 0.517, \(p\) < 0.001) affected the values of negative heterosis effects (Figure 4). When considering the effect of diversity of parental forms on significant SCA effects, no statistical significance was observed at the phenotypic (\(r\) = 0.021, \(p\) = 0.606) and genetic (\(r\) = 0.027, \(p\) = 0.573) levels (Figure 5). The results obtained (Figures 3 and 4) indicate the influence of genetic diversity of parental forms on heterosis effects. Potential relationships were tested for the subset of data for which the genetic distances of parental forms were greater than 0.6 (Figure 6). Figure 5: Relationships between diversity of parental forms (phenotypic and genotypic) and significant effects of specific combining ability. The yellow line denotes the trend line. Figure 6: Relationships between diversity of parental forms (phenotypic and genotypic) and values of breeding parameters (heterosis effect and SCA effect) obtained when genetic distance of parental forms was greater than 0.6. The yellow line denotes the trend line. The results obtained do not indicate any statistical significance. This is probably due to the fact that all effects of heterosis were considered, without separating by their sign and significance. The final stage of the study was to analyze the correlation between the values of genetic diversity of parental forms and the values of breeding parameters in situations when the effects of heterosis were statistically significant and when the genetic distances between parental forms were greater than 0.6. The results show that the genetic diversity of parental forms had a statistically significant effect on the positive (\(r=0.326\)) and negative (\(r=-0.426\)) values of heterosis.