Investigation of virus diseases in walnut and almond production areas in Hatay

This study was carried out to investigate viral infections in almond and walnut production areas in Altınözü, Antakya-Serinyol, Belen, Kırıkhan, Reyhanlı, Samandağ and Yayladağı districts of Hatay province. During the surveys in the orchards, a total of 243 plant samples belonging to 160 walnut and 70 almond and 13 weed species showing symptoms were collected and tested by biological indexing and DAS-ELISA methods for presence of arabis mosaic virus (ArMV), cherry leaf roll virus (CLRV), prune dwarf virus (PDV), plum pox virus (sharka virus-PPV), prunus necrotic ring spot virus (PNRSV). Phytoplasma infections were also analyzed by using molecular method (nested PCR- nPCR) in suspected almond and walnut samples. As a result of the analyzes made for almond samples, the highest infection rates were determined for PNRSV and PDV by the rate of 7.1%. These viruses were followed by ArMV (5.7%). CLRV and PPV were not determined in tested almond samples. The most common viruses were CLRV (8.7%) and PDV (4.3%) in walnut samples from Hatay province. Then, ArMV and PNRSV were detected by the rates of 2.5% and 1.8%, respectively. PPV was not determined in walnut samples. Virus infections were not found in walnut samples taken from nurseries in Samandağ district. One of the weed samples (Solanum nigrum) taken from a young walnut orchard was found positive for PPV infection for the first time. The main symptoms such as yellowing, reddish-purple discoloration of the leaves, decreasing in the number of leaves, multiple shoot regenerations or dieback of young shoots were observed on almond samples suspected for presence of phytoplasma infection. Almond samples analyzed by nested PCR (nPCR) method gave a positive result by the rate of 4/8.