Molecular Detection of Phytoplasmas in Prickly Pear (Opuntia fit indica) with Thickening of the Cladodio

摘要

During 2010 in Nopaltepec, Mexico, cactus plants were detected with symptoms of distortion and thickening of the cladode, mosaic, yellowing, proliferation and deformation of fruits in the whole plant or part of it. Since the syndrome has been attributed to phytoplasma infection, the objective of this study was to detect, the presence of phytoplasmas in different strata of the cladode and the roots of cactus plants by Polimerase Chain Reaction (PCR). The DNA extracted from cladodes with symptoms and asymptomatic, was amplified firstly with universal primers P1/P7, and PI/Tint, fragment of phytoplasma 16S rRNA gene, followed by nested PCR using the primers R16F2/R16R2, a fragment of 1 200 bp was obtained. Analysis of restriction patterns generated with endonucleases revealed that the phytoplasma belongs to the Mexican periwinkle virescence-16SrXIII.