Determination of Self and Cross-(In) Compatibility of some Asian Pear (Pyrus serotina Rehd.) and European Pear (Pyrus communis L.) Cultivars Native to Iran

In order to determine the self and cross-(in)-compatibility of nine Asian pear and two European pear cultivars native to Iran, two experiments were conducted based on complete randomized block design in two consecutive years (2012-2013). This study was performed in the experimental pear orchard in the Tarbiat Modares University, Tehran. Controlled pollination method was used in orchard and then pollen tube growth analysis by fluorescence microscopy was studied. Fruit set percentage was calculated 15, 35 and 75 days after full bloom. Pollinated flowers were picked 48, 72, 96 and 120 hours after pollination, fixed in FAA solution and stored at 4 ˚C until microscopic studies. Results showed that ‘KS9’ had the highest and ‘Sebri’ the lowest fruit set (7.85 and 0 % respectively). Results of controlled pollinations showed that the cultivars ‘Shahmiveh’, ‘Sebri’, ‘KS13’ and ‘KS7’ were self-incompatible and others were self-compatible.It can be concluded that cultivars ‘KS6’, ‘KS12’ and ‘KS13’ are cross-compatible, because their pollen tubes reached the ovaries 96h after pollination and the final fruit set was more than 8.98%.