Authors names: MSc Ioana GHIORGHIU RESEARCH REGARDING THE BEHAVIOUR OF APRICOT “TRAIAN” VARIETIY ON THE POLLINATION PROCESS Authors names: MSc Ioana GHIORGHIU Coordinator Conf. dr. Ligia ION International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Introduction Plum pox virus (PPV) infection causes the Sharka disease of Prunus, has spread from the Balkan countries throughout most of the European subcontinent and around the Mediterranean basin. Considerable economic loss and significant reduction in productive areas stimulated breeding programs aimed at enhancing resistance to the pathogen in such countries as Greece (Karayiannis et al. 1999), France (Audergon et al. 1994), Italy (Bassi et al. 1995), Spain (Egea et al. 1999), and the Czech Republic (Polák 1994). International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Introduction In Romania as a result of the intensive search for a source of resistance within available apricot germplasm and varieties, some Romanian cultivars [‘Traian’, ‘Amiral’, ‘Crystal’] were found to have natural resistance to PPV (L. Ion et al. 2012). These cultivars were used as donors for a resistance trait in conventional breeding programs based on crosses between resistant and the best local cultivars susceptible to virus. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Materials and Methods The apricot variety Faralia (‘Faralia בTraian’) was crossed as a female parent to ‘Traian’ a PPV (plum pox virus) resistant apricot cultivar, in the frame of the Faculty of Horticulture of University of Agronomical Science and Veterinary Medecine Bucharest Romania in 2018 spring. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Materials and Methods Crosses were performed by hand pollination with isolation of flowers after the petals and anthers removal from the flower buds. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Results and discussions In order to plan an efficient breeding program to obtain cultivars resistant to scab on the apricot cultivars, it is important to know the genetic control of this resistance. Although there is controversy about the genetic control of the resistance to PPV in apricot, some authors consider that resistance could be transmitted from resistant progenitors to offspring. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Results and discussions However, the descendants from crosses between susceptible and resistant cultivars segregated in a complex way. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Results and discussions In the table 1 we observed that the combination “Faralia x Traian” has 123 pollinated flowers, 21 fruits were bound, with a fruit binding percentage of 17%. Table 1. Table on the behavior of the Traian apricot variety in the pollination process Genitors Number of pollinated flowers Number of fruit bound – first determination Number of fruits at 10 days Percentage of fruit binding Percentage of fruit binding at 10 days Faralia x Traian 123 41 21 33 17 International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Results and discussions International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Conclusions and recommendations The identifying of a natural source of resistance to PPV, using this resistant source into new crosses with earlier commercial cultivars well adapted in our country, is an important step in order to implement the marker-assisted selection (MAS), based on markers tightly associated with resistance, as a measure to substantially streamline the breeding process. The” Traian” apricot variety is an excellent natural source of genetic resistance to PPV, and could be used in Romania breeding programs. International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania

Thank you for your kind attention! International Student Symposium "Hortus Academicus“ April 27, 2018 - Bucharest, Romania