Characterization of wild Solanum species at the molecular cytogenetics level: conservation, evolution, and breeding

Abstract

Biodiversity in Brazil is known as one of the richest in the world. The conservation of this biological diversity relies on the effective study and characterization of wild species. In this way, several approaches have been used including cytological data. One of the major challenges in the characterization of this biodiversity in the cytogenetic level, mainly in non-model plants, is the use of a robust strategy for the identification of individual chromosomes. For over one hundred years, classical cytogenetic was used but it is based only on chromosome morphological data, which limited the chromosome research application. Later, after the development of the fluorescent in situ hybridization (FISH) technique the power of cytogeneticists to answer biological questions increased considerably, but this gain was observed mainly in model plants. Recently, a new methodology was developed, and it is driving a revolution on the cytogenetics field. It is based on the use of bioinformatically selected oligonucleotides (oligo) as FISH probes (OligoFISH) and instead of being too polymorphic as the traditional probes, the oligo-based ones are conserved and highly versatile being usable to consistently identify the same chromosome in the target species. Interestingly, these probes showed to be useful in non-model plants, being a great technology to be introduced in Brazil, a country that has a vast number of uncharacterized wild plant species. Here we intend to use this cutting-edge technology associated with traditional cytogenetic approaches to construct a high-dense karyotype of different Solanum species, one of the most diverse group in Angiosperms. This will allow us to study different aspects of chromosome research including evolution, taxonomy and the potential of wild species for breeding. Based on that, we will concentrate our studies in two group of species (S. lycocarpum and S. calvescens) and their relatives. (AU)