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Grapevine leafroll disease (GLD) is an economically important virus disease affecting grapes (Vitis spp.) in almost all grape-producing areas, but little is known about its effect on metabolic constitutes of affected grapes. Fifty-seven suspicious grapevine samples of various cultivars showing symptoms of leaf curl, vein greening, reduced leaf size, necrosis, mosaics or reddening and reduced fruit yield and quality were collected during the summer of 2016–2017 in two regions of Azerbaijan and tested serologically (rapid one-step assay AgriStrip, DAS-ELISA) and molecularly (RT-PCR) for the presence of the major viruses infecting these crop. According to the result of serological tests, two cultivars (Saperavi and Narchicheyi) were found to be infected by GLRaV-3. RT-PCR using specific primers (LR3-8504V and LR3-9445C) for a part of the GLRaV-3 viral coat protein gene confirmed the presence of the virus by amplification of expected 942 bp fragments. The levels of some metabolic constituents were studied comparatively in the leaves of GLRaV3-infected and non-infected grapes and an increase of tocopherols, soluble sugars, total phenols, soluble protein, proline and glycine betaine was detected in infected grapes. Thus, it can be considered as an adaptive ability of various grapevine varieties against pathogen infection.

In the spring of 2012, sophora (Sophora alopecuroides L.) plants showing symptoms of leaf yellowing, little leaves and stunting were observed in Firooz-kuh (Tehran province), Sari (Mazandaran province) and Urmia (West Azerbaijan province) in Iran. Symptomatic plants from the three locations were subjected to nested polymerase chain reaction (PCR) to amplify 16SrRNA using primer pair P1/P7 followed by primer pair R16F2n/R16R2. The amplicons were purified, sequenced and the nucleotide sequences were analyzed by virtual restriction fragment length polymorphism (RFLP). The phytoplasmas associated with the yellows disease were identified as members of the 16SrIX group (Candidatus Phytoplasma phoenicium) and the 16SrXII group (Candidatus Phytoplasma solani). The two phytoplasmas were placed in 16SrIX-C and 16SrXII-A subgroups, respectively, in constructed phylogenetic trees. This is the first report on sophora yellows associated with Candidatus Phytoplasma phoenicium.

Eyvazi A., Dizadji A., Rastgou M., Koohi Habibi M. (2015): Bioassay and phylogeny of five Iranian isolates of Cucumber mosaic virus from different hosts based on CP gene sequence. Plant Protect. Sci., 51: 200–207.

During field surveys in 2013 and 2014, about 14 weed plants showing phytoplasma diseases symptoms including yellowing and witches’broom were collected and tested by polymerase chain reaction (PCR) using universal primers for 16SrRNA starting by primer pairs P1/P7 in first round PCR followed by primer pair R16F2n/R16R2 in nested PCR. The detected phytoplasmas were characterized and differentiated through sequence analysis of PCR-amplified rDNA and virtual restriction fragment length polymorphism (RFLP). The phytoplasmas detected in symptomatic horseweed (Erigeron canadensis L.), common madder (Rubia tinctorum L.), Johnson grass (Sorghum halepense [L.] Pers.) and Sophora root (Sophora alopecuroides L.) were identified as members of the clover proliferation group (16SrVI group) by construction of phylogenetic trees. Further analysis by virtual RFLP classified the phytoplasmas of Erigeron canadensis L. and Sorghum halepense L. in subgroup 16SrVI-A and phytoplasmas of Rubia tinctorum L. and Sophora alpecuriodes L. in subgroup 16SrVI-D. This is the first report on the occurrence of phytoplasma diseases of weeds in west Azarbaijan, Iran.

Phytoplasma-like symptoms were observed in plants of pepper (Capsicum annum), red cabbage (Brassica oleracea), common bean (Phaseolus vulgaris), maize (Zea mays), alfalfa (Medicago sativa), cucumber (Cucumis sativus), sunflower (Helianthus annus), tomato (Solanum lycopersicum) and squash (Cucurbita spp.) in West Azarbaijan province of Iran. The major symptoms observed were little leaf, witches’ broom, yellowing, phyllody, big bud and dwarfing of plants. DNA fragments of approximately 1800 and 1250 bp were amplified from 36 samples using universal primer pairs P1/P7 and R16F2n/R16R2 in first round and nested PCR, respectively. The phytoplasmas detected in maize, cucumber and tomato were characterized and differentiated through sequence analysis of PCR-amplified rDNA. These phytoplasmas were identified as members of the clover proliferation phytoplasma group (16SrVI group) and classified in subgroup 16SrVI-A. To the authors’ knowledge, this is the first report of the occurrence of 16SrVI phytoplasmas in maize.