PHYTOPLASMA DISEASES OF FRUIT TREES IN GERMPLASM AND COMMERCIAL ORCHARDS IN TURKEY
Ç. Ulubaş Serçe, M. Gazel, K. Çaglayan, M. Baş, L. Son
A survey was carried out in germplasm nurseries and commercial orchards from ten provinces in Turkey during 2003-2005. Samples were collected from trees showing European stone fruit yellows (ESFY) and Pear decline (PD) symptoms. A total of 270 stone fruit and six pear samples were tested by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). Universal phytoplasma primers P1/P7 and R16F2n/R2 were used for one-step and nested PCR assays, respectively. Nested-PCR products were digested with RsaI, SspI and MseI restriction enzymes. Twentyeight of 270 samples including plum, apricot, peach and almond were infected by Candidatus Phytoplasma prunorum. Infection rate by the same phytoplasma species of germplasm nurseries containing mostly foreign cultivars was 54.8%, whereas it was only 3.2% in commercial orchards. Ca. Phytoplasma prunorum was detected for the first time in Antalya, Gaziantep, Içel, Isparta, and Yalova provinces in local apricot cultivars as well as Japanese plum, apricot, and almond cultivars imported from Japan. PCR and RFLP tests of pear samples collected from commercial orchards in the Bursa province showed that the local pear cultivar ‘Deveci’ was infected by Candidatus Phytoplasma pyri, which was also found in the pear psyllid Cacopsylla pyri L. To our knowledge, this is the first report of detection of Ca. Phytoplasma pyri in C. pyri in Turkey.