THE POSSIBILITY OF ESFY PHYTOPLASMA TRANSMISSION: THROUGH FLOWERS AND SEEDS

ESFY phytoplasma (European Stone Fruit Yellows phytoplasma), recently named “Candidatus Phytoplasma prunorum”, is a long-standing problem in apricot and peach orchards in the Czech Republic. Two major ways of disease transmission in apricots are known at present. The basic method of transmission is through the natural occurrence of the sucking leafhopper, Cacopsylla pruni Scopoli. The second method of transmission is through vegetative propagation (such as cutting and grafting) during the production of young fruit trees in nurseries; however, until now, the possibility of ESFY transmission via flower structures and seeds had not been considered, but these preliminary findings indicate the presence of ESFY in seeds. Studies of ESFY infection in different plant tissues and organs appear to show that infection of apricot flowers and fruits (specifically, the flesh) is possible, although the presence of phytoplasma ESFY in pollen has not been demonstrated. Seeds from ESFY infected trees showed very low viability (21.6%) and practically no germination activity (9.4%).