Gypsy-like retrotransposons in Pyrenophora: an abundant and informative class of molecular markers.

This paper describes the development of S-SAP (sequence-specific amplified polymorphism) using a primer derived from the LTR (long terminal repeat) of the Pyggy retrotransposon isolated from Pyrenophora graminea. Fragments were amplified by S-SAP from different Pyrenophora spp., indicating the presence of Pyggy-like sequences in these genomes.

Determination of relative proportions of Globodera species in mixed populations of potato cyst nematodes using PCR product melting peak analysis.

Summary Using a novel approach based on melting peak analysis of PCR products, we have developed a semi-quantitative assay to measure the relative proportions of Globodera pallida and Globodera rostochiensis in a sample of potato cyst nematodes (PCN). The method depends on a competitive multiplex PCR where the products of each species can be separated by their distinct melting temperatures (T(m)). The melting curves of the products are measured by continual fluorescence monitoring in the presence of the intercalating dye SYBR Green I whilst gradually increasing the temperature.