Carya illinoinensis (pecan) is a fruit crop native to Mexico and the USA and cultivated across the world. Despite the advances of the molecular markers’ technologies and their use in genetic studies of diversity and breeding, studies with this species only reticently accompanied this progress. Here we review the studies using molecular markers, the gaps, and the perspectives concerning these technologies in pecaniculture. The selection of plants more adapted to the particular conditions where the species is cultivated and the obligatory outcrossing mode of reproduction lead the species to generate several new genetic combinations. Molecular markers were employed to assess this diversity, using PCR-based markers and sequencing-based technologies. Genetic diversity was characterised in natural populations and collections of pecan germplasm. Markers putatively linked to traits of interest were reported and the genome sequencing technology provided insights into the evolution of the species. The outcomes of these studies still have to be integrated and further exploited to reach and impact the orchards and breeding programmes. However, the scientific advances in molecular markers research and the growth of the pecan’s supply chain may drive to a scenario in which these biotechnologies will become tools regularly assisting breeders and farmers.

Pecan [Carya illinoinensis (Wangenh.) K. Koch] is a crop fruit native to the USA and Mexico currently cultivated in several countries, including Brazil, Uruguay, Argentina, Chile, Peru, China, South Africa, and Australia. Supported by the increasing consumption and market prices, the interest in the cultivation of this fruit crop is strongly growing around the world. In this study, AFLP and S-SAP markers were employed to characterize the genetic diversity of ancient accessions of pecan from southern Brazil. The evaluated plants were selected and preserved by the farmers and are remnants of the first introduction of seedlings from the U.S.A into southern Brazil aiming at developing research towards establishing commercial orchards. High levels of genetic diversity were estimated, suggesting that these plants have an important genetic background for the establishment of a germplasm collection with a wide genetic basis, for the development of breeding programs for this fruit crop. Cluster analysis of the genetic datasets revealed some correlation between the nuts’ morphometric traits and genetic markers. Such correlation should be further exploited. These ancient genotypes must be evaluated for other agronomic traits of interest and included in core collections of pecans.

Invasive plant species are expected to display high dispersal capacity but low levels of genetic diversity due to the founder effect occurring at each invasion episode. Understanding the history of invasions and the levels of genetic diversity of such species is an important task for planning management and monitoring strategy for these events. Peruvian Peppertree (Schinus molle L.) is a pioneer tree species native from South America which was introduced in North America, Europe and Africa, becoming a threat to these non-native habitats. In this study, we report the discovery and characterization of 17 plastidial (ptSSR) and seven nuclear (nSSR) markers for S. molle based on low-coverage whole-genome sequencing data acquired through next-generation sequencing. The markers were tested in 56 individuals from two natural populations sampled in the Brazilian Caatinga and Pampa biomes. All loci are moderately to highly polymorphic and revealed to be suitable for genetic monitoring of new invasions, for understanding the history of old invasions, as well as for genetic studies of native populations in their natural occurrence range and of orchards established with commercial purposes.

The objective of this work was to compare the purple garlic cultivated in the Planalto Catarinense region with the one in Midwestern/ Southeastern region of Brazil, concerning colorimetric and chemical aspects, as well as genetic patterns. The color of the bulbils was determined through colorimetric analysis, the volatile compounds were characterized by solid phase micro-extraction and gas chromatography, and the genetic diversity was analyzed using microsatellite markers. Garlic bulbs grown in the Planalto Catarinense region have a more intense purplish color. The samples from the Midwestern/Southeastern region present a significantly lower concentration of volatile compounds. There is no consistent genetic difference between samples from the Planalto Catarinense and Midwestern/Southeastern regions. The purple garlic from each cultivation region has singularities, mainly due to the farmers’ management method and edaphoclimatic factors. The uniqueness presented through the colorimetric and chemical analyses fulfills the basic requirements that are necessary for the Geographical Indication of these products.