Özet:

Leaves from 58 fig tree accessions showing different severity of mosaic and necrotic symptoms were collected in 2 different regions of Turkey and analysed by transmission electron microscope (TEM) and RT-PCR to determine putative causal agents of fig mosaic disease (FMD). Ultrastructural studies showed that double membrane-bound bodies (DMBs) were mainly observed in the parenchyma and mesophyll cells of infected leaves of the cultivars Göklop and Morgüz and some seedlings showing only mosaic symptoms. These bodies were surrounded by a fibrillar matrix in most of the infected cells. Long, flexuous rod-shaped virus-like particles (LFPs) were also observed in vascular tissues of the Bursa Siyahı, Sarılop, Sarızeybek, and Yediveren cultivars, as well as seedlings that exhibited mosaic and necrotic symptoms together. Isometric virus-like particles (IVLPs) were mainly observed in mesophyll parenchyma cells of cv. Yeşilgüz, which showed very mild mosaic symptoms. Some phytoplasma-like bodies, as well as mosaic symptoms, were also observed in the phloem tissues of cv. Morgüz, Göklop, and Yediveren. These kinds of particles were not observed in the healthy plant leaves. RT-PCR analyses revealed that a PCR product of 3.0 kbp was obtained from virus-purified RNA of cvs. Bursa Siyahı, and Sarılop and an unknown cultivar (seedling) using degenerate fig-associated primers. When primers specific for FMD agent in Spain were used, a DNA fragment of 750 bp was amplified from cvs. Göklop and Yeşilgüz. However, no product was obtained by using DC-random primers.

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