Genetic architecture of zinc hyperaccumulation in Arabidopsis halleri: the essential role of QTL x environment interactions.
This study sought to determine the main genomic regions that control zinc (Zn) hyperaccumulation in Arabidopsis halleri and to examine genotype x environment effects on phenotypic variance. To do so, quantitative trait loci (QTLs) were mapped using an interspecific A. halleri x Arabidopsis lyrata petraea F(2) population. *The F(2) progeny as well as representatives of the parental populations were cultivated on soils at two different Zn concentrations. A linkage map was constructed using 70 markers. *In both low and high pollution treatments, zinc hyperaccumulation showed high broad-sense heritability (81.9 and 74.7%, respectively). Five significant QTLs were detected: two QTLs specific to the low pollution treatment (chromosomes 1 and 4), and three QTLs identified at both treatments (chromosomes 3, 6 and 7). These QTLs explained 50.1 and 36.5% of the phenotypic variance in low and high pollution treatments, respectively. Two QTLs identified at both treatments (chromosomes 3 and 6) showed significant QTL x environment interactions. *The QTL on chromosome 3 largely colocalized with a major QTL previously identified for Zn and cadmium (Cd) tolerance. This suggests that Zn tolerance and hyperaccumulation share, at least partially, a common genetic basis and may have simultaneously evolved on heavy metal-contaminated soils.
Frérot
Hélène
H
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Faucon
Michel-Pierre
MP
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Willems
Glenda
G
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Godé
Cécile
C
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Courseaux
Adeline
A
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Darracq
Aude
A
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
Verbruggen
Nathalie
N
Laboratoire de Physiologie et de Génétique Moléculaire des Plantes, Université Libre de Bruxelles, Campus de la Plaine, CP242, boulevard du Triomphe, 1050 Bruxelles, Belgium.
Saumitou-Laprade
Pierre
P
Laboratoire de Génétique et Evolution des Populations Végétales, UMR CNRS 8016, Université des Sciences et Technologies de Lille - Lille1, F-59655 Villeneuve d'Ascq Cedex, France.
D000704:Analysis of Variance; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D002874:Chromosome Mapping; D020090:Chromosome Segregation / Q000187:drug effects / Q000235:genetics; D004777:Environment; D004785:Environmental Pollutants / Q000494:pharmacology; D005819:Genetic Markers; D040641:Quantitative Trait Loci / Q000235:genetics*; D019655:Quantitative Trait, Heritable; D015032:Zinc / Q000378:metabolism*
D004785:Environmental Pollutants; D005819:Genetic Markers; D015032:Zinc