Genetic Distinctiveness of Rye In situ Accessions from Portugal Unveils a New Hotspot of Unexplored Genetic Resources

Abstract

Rye (Secale cereale L.) is a cereal crop of major importance in many parts of Europe and rye breeders are presently very concerned with the restrict pool of rye genetic resources available. Such narrowing of rye genetic diversity results from the presence of “Petkus” pool in most modern rye varieties as well as “Petkus” × “Carsten” heterotic pool in hybrid rye breeding programs. Previous studies on rye's genetic diversity revealed moreover a common genetic background on landraces (ex situ) and cultivars, regardless of breeding level or geographical origin. Thus evaluation of in situ populations is of utmost importance to unveil “on farm” diversity, which is largely undervalued. Here, we perform the first comprehensive assessment of rye's genetic diversity and population structuring using cultivars, ex situ landraces along a comprehensive sampling of in situ accessions from Portugal, through a molecular-directed analysis using SSRs markers. Rye genetic diversity and population structure analysis does not present any geographical trend but disclosed marked differences between genetic backgrounds of in situ accessions and those of cultivars/ex situ collections. Such genetic distinctiveness of in situ accessions highlights their unexplored potential as new genetic resources, which can be used to boost rye breeding strategies and the production of new varieties. Overall, our study successfully demonstrates the high prospective impact of comparing genetic diversity and structure of cultivars, ex situ, and in situ samples in ascertaining the status of plant genetic resources (PGR).

Genomic Prediction Within and Among Doubled-Haploid Libraries from Maize Landraces

“…First, one must identify the most promising accessions, commonly based on passport data provided by seed banks and results from field trials, in which the landraces are evaluated for their per se performance and/or testcross performance with suitable testers (Salhuana and Pollak 2006;Böhm et al 2014). Selection among accessions is not sufficient because both molecular and phenotypic data from various crops suggest that more genetic variation lies within than between landraces (Greene et al 2014;Monteiro et al 2016;Böhm et al 2017;Mayer et al 2017). Therefore, the second challenge is mining the genetic diversity within landraces, preferably in the form of inbred lines.…”

Olive Tree (Olea europaea L.) Diversity in Traditional Small Farms of Ficalho, Portugal

“…All over the Mediterranean region, traditional agroecosystems are of great importance as incubators of crop diversity [32,45,46] and as ecological infrastructures in general, providing essential ecological services. Portugal is very rich in traditional crop diversity, and a few studies [47][48][49][50] have demonstrated the existence of unexplored genetic resources. At Ficalho, the farmers have been developing an on farm conservation project by promoting the selection and utilization of local germplasm, and it is common to explore unnamed trees as a consequence of their agronomic characteristics.…”

Aran Islands, Western Ireland: Farming History and Environmental Change, Reconstructed from Field Surveys, Historical Sources, and Pollen Analyses

“…1300 BC) (Jansen 2011:114, van den Brink andJanssen 1985). Interestingly, recent genetic investigations have shown that rye cultivated by farmers in Serra da Estrela and adjoining uplands in northern Portugal has an unexpectedly high level of genetic distinctiveness so that these crops, and possibly also crops from similar cultural landscapes, such as the Aran Islands, may have considerable potential in cereal breeding programmes (Monteiro et al 2016).…”

“…The information presented also serves to emphasize the importance of traditional farming, in its varied manifestations, for maintaining high biodiversity, especially in exceptional and sensitive environments such as the Aran Islands. Furthermore, as demonstrated by Monteiro et al (2016) for Portugal, the rye and oat crops on the Aran Islands may have exceptional genetic characteristics of potential value in crop breeding programmes. It is therefore important that initiatives such as the EU-funded Aran Life Project (https://www.aranlife.…”