Spontaneous gene flow and population structure in wild and cultivated chicory, Cichorium intybus L.

Abstract

Spontaneous gene flow between wild and cultivated chicory, Cichorium intybus L., may have implications for the genetic structure and evolution of populations and varieties. One aspect of this cropwild gene flow is the dispersal of transgenes from genetically modified varieties, e.g. gene flow from GM chicory to natural chicory could have unwanted consequences. With the purpose to identify and quantify crop-wild gene flow in chicory, we analysed introgression in 19 wild chicory populations and 16 accessions of chicory varieties and landraces distributed across Northern, Central and Mediterranean Europe. The analysis used 281 AFLP markers and 75 SSAP markers giving a total of 356 polymorphic markers. Results from model based assignments with the program STRUCTURE indicated many incidents of recent gene flow. Gene flow was observed both between cultivars and wild populations, between landraces and wild populations, between different wild populations as well as between cultivars. Population structure visualized by distance-based clustering showed a North-South geographical structuring of the wild populations, and a general grouping of the cultivars corresponding to known origin. The results indicated, however, that the structuring between the two groups of wild and cultivated types was weak. As crop and wild recipients are genetically close and genes are transferred between the two types rather frequently, focus on mitigating crop-wild gene flow should be increased, before transgenic varieties are cultivated openly.

Population structure of South African and Australian Pyrenophora teres isolates

“…It was indicated previously that the ability of structure to converge to a robust solution is reduced when using systems with a complex structure (Stajner et al. , 2008; Kiær et al. , 2009).…”

Hybridization between crops and wild relatives: the contribution of cultivated lettuce to the vigour of crop–wild hybrids under drought, salinity and nutrient deficiency conditions

“…Multiple studies have focused on the rate of hybridization between crops and wild relatives (Arias and Rieseberg 1994 ; Hoc et al 2006 ; D’Andrea et al 2008 ; Giannino et al 2008 ; Kiær et al 2009 ), and on the occurrence of hybrids and their fitness in relation to the fitness of the wild parent (Snow et al 2003 ; Hooftman et al 2005 , 2009 ; Campbell and Snow 2007 ). However, few studies have been conducted with the aim of understanding the specific contribution of the crop and wild parents to the fitness of the hybrids, the role of the genomic locations of the genes (as for instance assessed through quantitative trait loci (QTL), Baack et al 2008 ), and the role of epistasis and genotype by environment interaction on the fitness or vigour of the hybrids.…”

Insights into the Sesquiterpenoid Pathway by Metabolic Profiling and De novo Transcriptome Assembly of Stem-Chicory (Cichorium intybus Cultigroup “Catalogna”)

“…Culti-groups are mostly allogamous due to different mechanisms of self-incompatibility (Eenink, 1981, 1982; Varotto et al, 1995) and natural hybrids widely occur (Kiaer et al, 2009; Bai et al, 2012). Consistently, the “Catalogna” sub-group shows a high genetic variation at both inter- and intra- population levels (Raulier et al, 2016).…”