Abstract The present study was carried out to determine the effect of quince rootstocks (BA29, QA and MC) on plant growth, fruit quality and yield of ‘Santa Maria’ pear cultivar in 2020 and 2021. In this study, significant differences were determined by all growth, yield and quality parameters except for trunk diameter (TD), trunk cross-sectional area (TCSA), canopy volume, fruit stalk thickness, acidity, total soluble solids (TSS) in terms of research years and rootstocks from analysis of variance. Tree height, annual shoot length, leaf area, fruit weight, fruit width, and fruit length was lower in the MC rootstock than in the others. In the case of research years, out of annual shoot growth in 2020, all other parameters were higher in 2021. Fruit stalk length, fruit stalk thickness and fruit firmness were higher on MC rootstock than BA29 and QA. There was an insignificant difference between rootstocks in terms of TSS. The highest L* was in QA and MC; chroma was in QA and hue angle was in BA29 rootstock. The number of fruit was the highest (139.01 pieces/tree) in BA29 in 2021 and the lowest in MC (11.97 pieces/tree) in 2020. The highest yield per tree (30.62 kg), yield per hectare (58484.2 kg), yield per trunk cross-sectional area (2.24 kg/cm2) and yield per canopy volume (71.21 kg/m3) were measured in QA in 2021. In conclusion, the yield efficiency of ‘Santa Maria’ pear cultivar under high density planting on QA was better than other combinations in 2021. Since the plants on which the research is carried out are still young, it may be recommended to continue the research for many years to determine the most suitable rootstock. BA29, BA (BA29 Santa Maria 202 TD, TD , (TD) crosssectional cross sectional TCSA, TCSA (TCSA) acidity TSS (TSS variance height weight width others BA2 L 139.01 13901 139 01 (139.0 pieces/tree piecestree pieces 11.97 1197 11 97 (11.9 30.62 3062 30 62 (30.6 kg, kg kg) 58484.2 584842 58484 2 (58484. 2.24 224 24 (2.2 kg/cm2 kgcm2 kgcm cm2 cm 71.21 7121 71 21 (71.2 kg/m3 kgm3 kgm m3 m conclusion young (BA2 20 (TD (TCSA 139.0 1390 13 0 (139. 11.9 119 1 9 (11. 30.6 306 3 6 (30. 58484. 5848 (58484 2.2 22 (2. kg/cm 71.2 712 7 (71. kg/m (BA 139. (139 11. (11 30. (30 584 (5848 2. (2 71. (71 (13 (1 (3 58 (584 ( (7 5 (58 (5

Objective The aim of this study was to investigate retrorenal colon incidence in percutaneous nephrolithotomy (PNL) interventions made in our clinic. Materials and Methods Clinical data of 804 PNL patients, accumulated over a 7 year period (2006-2012), was surveyed. The patient files were reviewed retrospectively, and only those who had abdominal computed tomography (CT) images before PNL intervention were included in the study. In the CT images, the position of both the ascending and descending colon in relation to the right and left kidneys were evaluated. Results According to our hospital reports, 394 patients with CT images were included in the present study 27 patients (6.9%) had retrorenal colon, of which 18 (4.6%) were on the left side, 4 (1.0%) on the right side and 5 (1.3%) had bilateral retrorenal colons. Colonic perforation complication was seen only in two patients and the colonic perforation rate was 0.3%. These two cases had no CT images. Conclusions PNL, in the process of becoming the standard treatment modality, is a safe and reliable technique for renal stone treatment. Colonic injury should be taken into consideration during PNL interventions of the lower pole of the kidney (especially on the left side) due to the location of retrorenal colon.