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Title: A derived weedy rice × ancestral cultivar cross identifies evolutionarily relevant weediness QTLs
Abstract Weedy rice (Oryzaspp.) is a weedy relative of the cultivated rice that competes with the crop and causes significant production loss. The BHA (blackhull awned) US weedy rice group has evolved fromauscultivated rice and differs from its ancestors in several important weediness traits, including flowering time, plant height and seed shattering. Prior attempts to determine the genetic basis of weediness traits in plants using linkage mapping approaches have not often considered weed origins. However, the timing of divergence between crossed parents can affect the detection of quantitative trait loci (QTL) relevant to the evolution of weediness. Here, we used a QTL‐seq approach that combines bulked segregant analysis and high‐throughput whole genome resequencing to map the three important weediness traits in an F2population derived from a cross between BHA weedy rice with an ancestralauscultivar. We compared these QTLs with those previously detected in a cross of BHA with a more distantly related crop,indica. We identified multiple QTLs that overlapped with regions under selection during the evolution of weedy BHA rice and some candidate genes possibly underlying the evolution weediness traits in BHA. We showed that QTLs detected with ancestor–descendant crosses are more likely to be involved in the evolution of weediness traits than those detected from crosses of more diverged taxa.  more » « less
Award ID(s):
1947609
PAR ID:
10492531
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Molecular Ecology
Date Published:
Journal Name:
Molecular Ecology
Volume:
32
Issue:
22
ISSN:
0962-1083
Page Range / eLocation ID:
5971 to 5985
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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