## 3 Results and Discussion
### Evaluation of the Impedance of the Pear Grafting Zone  
The diameter of the root neck of the treated samples was similar to that in the control, and the leaf development of the treated young trees was on average 13% better than in the control four months after the grafting (data not shown). The length of the trees was measured on the seventh day after planting, and then once a week for 91 days. The treated samples showed a slightly faster growth, but the differences with the control remained statistically insignificant to the end of the experiment (Figure 7).  
The treated trees significantly differed from the control ones starting from 6 months after grafting (Figure 8a). The comparison showed that the length of the trees in the control group was 13.57% less than in the DBD CAP group (Figure 8b) and 17.43% less than in the PTS:DW group (Figure 8c). Moreover, the treated young trees showed a better development of the root system.  
The impedance module of the grafting zone after compensation of the capacitive transition of the electrodes is shown in Figure 9. As can be seen from the graph, in the  
Figure 6: Dependence of the impedance modulus on the frequency for different distance between the electrodes, taking into account the parasitic capacitance (4 months after the grafting; pear tree diameter of 12 mm).  
Figure 7: The average length of the grafted young pear trees after planting in the greenhouse.  
first 3 weeks after grafting, the impedance was at the control level. Among the significant indicators, the largest deviation in the control and PTS:DW was observed at week 4, with 21.6%, control, and DBD CAP at week 10, with 52.5%. Starting from the ninth week of observation, the minimum value of the control deviation and PTS:DW was 26.83%, and the deviation of the control and DBD CAP was at least 31%, which may indicate a better healing process of grafted young trees, probably due to better development of vascular plant tissues.  
Figure 8: Visual comparison of young trees development after 6 months of growth; (**a**) 30 s DBD CAP; (**b**) control, (**c**) PTS:DW. The arrow indicates the places of grafting.  
Figure 9: Changes in the impedance modulus of the grafting zone after subtracting the parasitic capacitance of the electrodes (4 months after grafting). All data are mean \(\pm\) SD from triple repetitions. Statistically significant differences (\(p<0.05\)) relative to control were calculated with Student’s t-test and are marked with an asterisk (*).  
Overall, the observed positive effects can result from a combination of the effects triggered by the treatment of the cut surfaces of the scion and rootstock with CAP and PTS. Likely, the cut surface was additionally disinfected by reactive oxygen and reactive nitrogen species; they were also made smoother, making the contact of the cut surfaces tighter [25]. All this improved the survival rate of the grafting and plant resilience to the stress imposed by the grafting.  
The proposed technique can be used to forecast survival of the grafted scion early after the grafting, whereas conventional methods allow assessing the success of the grafting only after planting the grafted young trees in the nursery.  
The device developed in this work was found to be easy to use. After conducting a full cycle of experiments and tests with the development of a methodology, this method can also become a substitute for the traditional methods for assessing the water content in the stem and branches of tress. Our method also allowed us to trace the dynamics of the graft joint healing, to judge the quality of the grafting in the early stages, and to predict outcomes of grafting as well as the development of the complete plant [22; 26].