Detection of aster yellows group (subgroup 16SrI-B) phytoplasma in oats based on nested PCR and RFLP in Lithuania

L. Urbanavičienė, D. Valiūnas and R. Jomantienė

Institute of Botany, Plant Virus Laboratory,Žaliųjų Ežerų 49, LT-08406 Vilnius, Lithuania; e-mail: urbanala@botanika.lt

Abstract:

Phytoplasma strains were detected in oats (Avena sativa L.) in Lithuania exhibiting disease symptoms of stunting, sterile, deformed and yellow spikes. A phytoplasma-characteristic 1.8 kb and 1.2 kb rDNA PCR products were amplified from DNAs of all diseased but not healthy oat plants tested, using phytoplasma universal primer pairs P1/P7 and R16F2n/R16R2 confirming that symptomatic plants were infected by phytoplasma. Phytoplasma was termed oat stunt (OatSt). Restriction fragment length polymorphism (RFLP) analysis of amplified 16S rDNA indicated that diseased oats were infected by phytoplasma belonging to the group 16SrI (aster yellows, AY, group) and subgroup 16SrI-B. This is the first report of phytoplasma belonging to 16SrI (aster yellows) group and 16SrI-B phytoplasma subgroup identified in oat plants.

Key words:

16S rRNA gene, Avena sativa, PCR, phytoplasma, RFLP

Molecular detection and characterization of phytoplasma infecting Celosia argentea L. plants in Lithuania

M. Samuitienė and M. Navalinskienė

Institute of Botany, Žaliųjų Ežerų 49, Vilnius LT-08406, Lithuania;e-mail: msamuit@botanika.lt

Abstract:

Symptoms of diseased Celosia argentea L. plants included flower phyllody, general yellowing and stunting of plants. Amplification of phytoplasmal 16S rRNA gene sequence, in PCRs containing phytoplasma universal primer pairs P1/P7, R16F2n/R16R2 and template DNA extracted from diseased C. argentea plants, confirmed that the plants were infected by phytoplasma. The 1.2 kbp 16S rDNA product of nested PCR, primed by primer pair R16F2n/R16R2 was subjected to single enzyme digestions with 8 restriction endonucleases. RFLP analysis revealed that the plants were infected by a phytoplasma belonging to group 16SrI (aster yellows phytoplasma group), subgroup I–M. Strains in this subgroup have a broad pathogenic potential, since they infect a wide range of plant host species.

Key words: