Molecular Evidence for the Presence of Aster Yellows-Related Phytoplasmas in Lilies with Leaf Scorch and Flower Virescence

Severe leaf scorch symptoms occurred on oriental lily hybrids cv. Woodri€ʹs Memory cultivated in two commercial greenhouses in Poland. Symptoms included leaf necrosis and malformation, ¯ower bud abscission and ¯ower virescence, distortion and abortion. Natur- ally infected lily plants with severe symptoms in 1999 had retarded growth and leaf chlorosis and they failed to ¯ower the following year. The presence of phytoplasmas in diseased lilies was demonstrated using nested poly- merase chain reaction (PCR) assays with universal and 16SrI group speci®c primer pairs that ampli®ed the phytoplasma 16S rDNA fragment. The PCR products (1.1 kb) of all samples used for restriction fragment length polymorphism analysis had the same restriction pro®les after digestion with endonucleases AluI and MseI. The restriction pro®les of phytoplasma DNA from these plants corresponded to those of an aster yellows phytoplasma reference strain.