RESUMO
Investigations included six traditional pear landraces (Pyrus communis L.): Aleksandra, Vodenka, Patlidjanka, Ljubichica, Tatlikuti and Crvenushka. The number of seeds per fruit, seed energy and total seed germination were investigated and statistically analysed (P = .05 and P = .01). Seed stratification encompassed pre-chilling by using three treatments: I treatment covers seed pre-chilling at -18°C for 24 hours; II treatment covers seed pre-chilling at +1°C for 2 weeks; III treatment covers seed pre-chilling at +8°C for 1 week. Only Patlidjanka belongs to the group with high seed number in the fruit. The other landraces produced low seed number like 2-3 seeds per fruit. The average number of all researched landraces is 3.67 seeds per fruit. The pear Tatlikuti showed a very high significant difference (P = .01). It was concluded that III treatment showed the highest seed energy at landraces Ljubichica 77.5% and Tatlikuti 75.0% and the lowest at Aleksandra 52.5%. There were significant differences (P = .05) between the applied treatments regarding seed energy. In II treatment, the total seed germination had the highest effect on Patlidjanka 87.75%. The values for germination seeds in the other landraces were in the range of 77.5% to 86.25%. Statistically, a significant difference was determined in the landraces Ljubichica and Crvenushka (P = .05), and there was high significant difference (P = .01) in the pear Aleksandra. The II and III treatments could be recommended as the most suitable to improve the pear seed germination.
RESUMO
Up-to-date, there is no methodical and long-term research on fruit quality and nutritional characteristics of peppers grown in organic production system in Republic of Macedonia. Still, there are debates in broad sense about the advantage of organic vegetable production compared to conventional one in terms of quality characteristics. Led by this idea, this research was conducted with an aim to study vitamin C content and total antioxidant content in fruits of six pepper genotypes as most important fruit quality characteristics and to determine if there are differences in fruit quality properties between those grown in organic and conventional production system. Fruits of six different pepper genotypes Strumicka Kapija, Strumicka Vezena, Piran, Zupska Rana, Duga Bela and Kurtovska Kapija cultivated in organic and conventional production systems were used for determination of vitamin C and total antioxidant content. The extraction of vitamin C and total antioxidants were performed in a plant tissue extractor with orthophosphoric acid and methanol as extracting reagents, respectively. Vitamin C content was determined by HPLC instrument, while total antioxidant content was measured with potentionstat instrument. The genotype Strumicka Kapija was characterized with the highest content of vitamin C in both cultivation systems. In all genotypes under study, except Zupska Rana, the vitamin C content was higher in fruits from organic production as compared to pepper fruits from the conventional system. Generally, the total antioxidant content in pepper fruits from the conventional system was averagely lower than the total antioxidant content measured in pepper fruits from the organic production system. These findings are a prove that production system is very important for the fruit quality characteristic and the organic production of peppers results with production of fruits with higher content of vitamin C and antioxidants compared to conventional ones, therefore organic peppers give more nutrition and health benefits to consumers.