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Title: Genomic insights into the origin, domestication and diversification of Brassica juncea
Abstract

Despite early domestication around 3000 BC, the evolutionary history of the ancient allotetraploid speciesBrassica juncea(L.) Czern & Coss remains uncertain. Here, we report a chromosome-scale de novo assembly of a yellow-seededB. junceagenome by integrating long-read and short-read sequencing, optical mapping and Hi-C technologies. Nuclear and organelle phylogenies of 480 accessions worldwide supported thatB. junceais most likely a single origin in West Asia, 8,000–14,000 years ago, via natural interspecific hybridization. Subsequently, new crop types evolved through spontaneous gene mutations and introgressions along three independent routes of eastward expansion. Selective sweeps, genome-wide trait associations and tissue-specific RNA-sequencing analysis shed light on the domestication history of flowering time and seed weight, and on human selection for morphological diversification in this versatile species. Our data provide a comprehensive insight into the origin and domestication and a foundation for genomics-based breeding ofB. juncea.

 
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NSF-PAR ID:
10306575
Author(s) / Creator(s):
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Publisher / Repository:
Nature Publishing Group
Date Published:
Journal Name:
Nature Genetics
Volume:
53
Issue:
9
ISSN:
1061-4036
Page Range / eLocation ID:
p. 1392-1402
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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