Assessment of Fruit Set Percentage and Pollen Compatibility Status in Different Apricot Cultivars

Self-incompatibility in apricot (Prunus armeniaca L.) trees and their need for pollination with other cultivars results in unsustainable yield and loss of traditional production. Study of pollen compatibility among different cultivars is needed to guarantee of fertility outcome and sustainable fruit production in new apricot cultivars. In current work, the final fruit set was studied for apricot promising genotypes after controlled cross-pollination in the field conditions in two successive years. Also, their (in) compatibility statues was evaluated by tracking of pollen tube growth through the ovary by fluorescent microscopy approach. The presence of at least one growing pollen tube inside the ovary 96 h after pollination was considered as the sign of compatibility, but block of pollen tube growth through the style was considered as the sign of incompatibility between pollinizer and recipient genotypes. According to our data, all of pollinizers include of GER, Aybatan, HB190, NM177 and KOSH269 were compatible with recipient genotypes. However, the most percentage of final fruit set in Ordoubad90 was achieved when it was pollinated with NM177 and Aybatan pollinizers, in ASG and AD503 genotypes were achieved when they were pollinated with Aybatan and GER pollinizers, and finally in AD740 genotype was achieved when it was pollinated with NM177, Aybatan and GER pollinizers. Additionally, AD503 had more (47% fruit set) but Ordoubad90 had less (23% fruit set) fertility potential among recipient genotypes. Also, microscopic observations confirmed the results of final fruit set following controlled cross-pollination in the field.