## 3 Results
### Effect of Bulk Density and Water Holding Capacity on Cucumber Fruit Yield and Quality
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multicolumn{2}{c}{**Yield of Fruit**} & \multicolumn{3}{c}{**MW/Control EC**} & \multicolumn{3}{c}{**L/Control EC**} & \multicolumn{3}{c}{**MW/High EC**} & \multicolumn{2}{c}{**L/High EC**} \\ \cline{3-10}  & **R** & **D (\%)** & **R** & **D (\%)** & **R** & **D (\%)** & **R** & **D (\%)** \\ \hline Total yield & Number of fruits & 0.7007 & 49.10 & 0.9999 * & 99.99 & 0.7376 & 54.41 & 0.8164 & 66.65 \\  & Weight of fruit & 0.7190 & 51.70 & 0.9783 & 95.71 & 0.5647 & 31.89 & 0.6821 & 46.53 \\ \hline Marketable yield & Number of fruits & 0.8119 & 65.93 & 0.9989 * & 99.79 & 0.2729 & 7.45 & 0.8257 & 68.18 \\  & Weight of fruit & 0.8102 & 65.64 & 0.9820 * & 96.43 & 0.2383 & 5.68 & 0.7631 & 58.23 \\ \hline Unmarketable yield & Number of fruits & 0.9433 & 88.99 & 0.9972 * & 99.44 & 0.9339 & 87.22 & 0.2998 & 8.99 \\  & Weight of fruit & 0.7972 & 63.65 & 0.9903 * & 98.07 & 0.9339 & 87.22 & 0.4240 & 17.79 \\ \hline Number of aborted fruit & 0.9577 & 91.73 & 0.9821 * & 96.47 & 0.8571 & 73.47 & 0.8839 & 78.13 \\ \hline \hline \end{tabular}  
* significant at \(p\leq 0.05\). <25%—low impact, 25-45%—average impact, 46-100%—high impact.  
\end{table} 
Table 9: Multiple correlation coefficient (R) and coefficient of determination (D) for cucumber yield versus substrate type and medium EC. Effect of Bulk Density and Water Capacity of the Substrate on Dry Matter, Tss and Bioactive Compound Content of Fruit  
Using the standard EC of the medium in mineral wool mats, a negative correlation was obtained between bulk density and TSS and \(\beta\)-carotene content in cucumber fruits (Table 12). Coefficients of determination (D) illustrating the influence of selected physical substrate characteristics on dry matter and TSS content in fruit were low and amounted to 15.19% and 12.57%, respectively (Table 13).This indicates a slight influence of the studied substrate characteristics on the discussed parameters (Table 13). Additionally, no significant correlation was obtained between the physical properties of the substrates and the quality of fruits from plants grown in mineral wool and fertilized with high EC medium (Table 12). There was a significant positive correlation between WHC and lutein content in fruits from plants grown in lignite substrate, both fertilized with standard and high EC medium (Table 12). It was also confirmed by high coefficient of determination (D) and value of multiple correlation coefficient R, which was 0.8411 for plants fertilized with standard EC and 0.8211 for those fertilized with high EC nutrient solution (Table 13). On the other hand, no relationship was found between cucumber fruit dry matter, TSS, \(\beta\)-carotene and nitrate content and physical properties of both lignite and mineral wool substrates, irrespective of medium EC (Tables 12 and 13). \begin{table}
\begin{tabular}{c c c c c c} \hline
**Treatment** & **Physical Parameter of the Substrate** & **Firmness** & **C*** & **H*** & **a*/b*** \\ \hline MW/control EC & BD & \(-\)0.0451 & 0.1603 & 0.7442 * & 0.7326 * \\  & WHC & \(-\)0.6256 & \(-\)0.2896 & 0.2782 & 0.2539 \\ \hline L/control EC & BD & 0.6514 * & \(-\)0.8071 * & 0.5791 & 0.5685 \\  & WHC & \(-\)0.0824 & 0.0352 & 0.1120 & 0.1211 \\ \hline MW/high EC & BD & 0.1770 & \(-\)0.8633 * & \(-\)0.5064 & \(-\)0.5065 \\  & WHC & \(-\)0.6722 * & \(-\)0.4783 & 0.0569 & 0.0598 \\ \hline L/high EC & BD & \(-\)0.4663 & 0.0517 & 0.4614 & 0.4581 \\  & WHC & \(-\)0.6221 & 0.1485 & 0.6603 & 0.6616 \\ \hline \end{tabular} * significant at \(p\leq 0.05\).  
\end{table} 
Table 10: Linear correlation coefficient(2) for the relationship between firmness of fruit, fruit skin color traits in the CIE Lab system: C* (color saturation), H* (color intensity) and a*/b* color index, and physical parameters of the medium (BD, WHC) depending on the type of medium and EC of the medium.