Data from: Extreme QTL mapping of germination speed in Arabidopsis thaliana

Seed germination is a key life history transition for annual plants and
partly determines lifetime performance and fitness. Germination speed, the
elapsed time for a nondormant seed to germinate, is a poorly understood
trait important for plants’ competitiveness and fitness in fluctuating
environments. Germination speed varied by 30% among 18 Arabidopsis
thaliana populations measured, and exhibited weak negative correlation
with flowering time and seed weight, with significant genotype effect (P
< 0.005). To dissect the genetic architecture of germination speed,
we developed the extreme QTL (X-QTL) mapping method in A. thaliana. The
method has been shown in yeast to increase QTL mapping power by
integrating selective screening and bulk-segregant analysis in a very
large mapping population. By pooled genotyping of top 5% of rapid
germinants from ~100 000 F3 individuals, three X-QTL regions were
identified on chromosomes 1, 3 and 4. All regions were confirmed as QTL
regions by sequencing 192 rapid germinants from an independent F3
selection experiment. Positional overlaps were found between X-QTLs and
previously identified seed, life history and fitness QTLs. Our method
provides a rapid mapping platform in A. thaliana with potentially greater
power. One can also relate identified X-QTLs to the A. thaliana physical
map, facilitating candidate gene identification.