Detection and molecular identification of ‘Candidatus phytoplasma trifoli’ infecting some cultivated crops and vegetables in West Azarbaijan province, Iran

Abstract

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.