The phytoplasma associated diseases are an emerging threat to fruit and vegetable crops leading severe yield losses worldwide. Pear (Pyrus communis L.) trees, with symptoms of severe reddening, dwarfing and shoot proliferation were observed in pear orchards of Malatya province of Turkey. Tomato (Solanum lycopersicum L.) plants grown nearby the symptomatic pear orchard displaying leaf rolling, severe flower sterility and purple leaves were observed at the same agroecosystem. To verify the presence and diversity of phytoplasmas, symptomatic pears and tomatoes were sampled and weeds nearby the symptomatic plants were collected. Total plant DNA was purified from midrib of collected leaves using a commercial kit. The DNA samples were analyzed by nested polymerase chain reaction (PCR) using universal primer pairs to amplify 16S rDNA fragments. The phytoplasmas detected in collected samples were differed according to the host. Here we detected and characterized ‘Candidatus Phytoplasma pyri’ belonging to apple proliferation group (subgroup 16SrX-C) from a pear tree, ‘Candidatus Phytoplasma trifolii’ belonging to clover proliferation group (subgroup 16SrVI-A) from a weed (Amaranthus retroflexus) and ‘Candidatus Phytoplasma solani’ belonging to the stolbur phytoplasma group (subgroup 16SrXII-A) from a tomato plant. Direct sequencing of PCR products verified the phytoplasmal nature of the infections. The occurrence of ‘Ca. P. trifolii’ on A. retroflexus is the first report for the world. The irregular presence of the phytoplasmas in fruit and vegetable crops and weeds indicates continuous spread of the phytoplasmas threatening the new crops and new horizons.

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Grapevine (Vitis vinifera L.) is one of the most important fruit crops in Turkey and viral diseases are one of the main problems of grapevine production. They decrease yield quantity and quality of crops as well as cause death of the plants in an interaction with other agents. Leafroll disease of grapevine, caused by a complex of viruses, is considered a serious threat to production across many grapevine growing regions in Turkey. This study was conducted to determine the current status of Grapevine leafroll-associated viruses (GLRaVs) in Malatya province. Grapevine plantations in Malatya province were surveyed for the presence of Grapevine leafroll-associated viruses (GLRaVs) -1, -2, -3, -4 and -6.Purposive sampling was done in vineyards of Arapgir, Darende and Battalgazi districts, which are the primary grapevine producing areas of Malatya during 2016-2017 growing seasons. A total of 241 samples were collected and tested by DAS-ELISA. Samples giving two fold of absorbance values (405 nm) of negative control were evaluated as positive. According to the results, 131 samples were found to be infected with GLRaV-1, whereas 48 samples with GLRaV-3 and -4 samples with GLRaV-4. None of the samples were reacted as positive against GLRaV-2 and GLRaV-6. Forty five samples were found to be infected with mix infection of GLRaV-1 and -3, and three samples were found to be infected with GLRaV-1 and -4 strain 6.

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