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Cultivated peanut (Arachis hypogaeaL.) has a narrow genetic base and is isolated from its wild relatives. This genetic bottleneck results in a lack of strong resistance to biotic and abiotic stress. However, high levels of genetic variation and resistance exist among the wild relatives. In order to enlarge the genetic base of cultivated peanut and introgress beneficial alleles from the wild relatives, interspecific hybrids were produced among a set of selected diploid species. Upon colchicine treatment, fertile allotetraploids were recovered from three combinations including (A. ipaënsisKG 30076  ×A. correntinaGKP 9530)^4x(Reg. no. GP‐241, PI 695391), (A. ipaënsisKG 30076 ×A. duranensisKGBSPSc 30060)^4x(Reg. no. GP‐242, PI 695392), and (A. validaKG30011 ×A. stenospermaV 10309)^4x(Reg. no. GP‐243, PI 695393). All of them demonstrated high levels of resistance to leaf spot diseases in the field. Tolerance toTomato spotted wilt viruswas found in (A. validaKG 30011 ×A. stenospermaV 10309)^4x. These newly created allotetraploids are cross‐compatible with cultivated peanut. These genetic resources will provide peanut breeding researchers with new sources of disease resistances to improve the agronomic performance of cultivated peanut.

We report reference‐quality genome assemblies and annotations for two accessions of soybean (Glycine max) and for one accession ofGlycine soja, the closest wild relative ofG. max. TheG. maxassemblies provided are for widely used US cultivars: the northern line Williams 82 (Wm82) and the southern line Lee. The Wm82 assembly improves the prior published assembly, and the Lee andG. sojaassemblies are new for these accessions. Comparisons among the three accessions show generally high structural conservation, but nucleotide difference of 1.7 single‐nucleotide polymorphisms (snps) per kb between Wm82 and Lee, and 4.7 snps per kb between these lines andG. soja.snpdistributions and comparisons with genotypes of the Lee and Wm82 parents highlight patterns of introgression and haplotype structure. Comparisons against the US germplasm collection show placement of the sequenced accessions relative to global soybean diversity. Analysis of a pan‐gene collection shows generally high conservation, with variation occurring primarily in genomically clustered gene families. We found approximately 40–42 inversions per chromosome between either Lee or Wm82v4 andG. soja, and approximately 32 inversions per chromosome between Wm82 and Lee. We also investigated five domestication loci. For each locus, we found two different alleles with functional differences betweenG. sojaand the two domesticated accessions. The genome assemblies for multiple cultivated accessions and for the closest wild ancestor of soybean provides a valuable set of resources for identifying causal variants that underlie traits for the domestication and improvement of soybean, serving as a basis for future research and crop improvement efforts for this important crop species.

Spirodela polyrhizais a fast‐growing aquatic monocot with highly reduced morphology, genome size and number of protein‐coding genes. Considering these biological features of Spirodela and its basal position in the monocot lineage, understanding its genome architecture could shed light on plant adaptation and genome evolution. Like many draft genomes, however, the 158‐Mb Spirodela genome sequence has not been resolved to chromosomes, and important genome characteristics have not been defined. Here we deployed rapid genome‐wide physical maps combined with high‐coverage short‐read sequencing to resolve the 20 chromosomes of Spirodela and to empirically delineate its genome features. Our data revealed a dramatic reduction in the number of therDNArepeat units in Spirodela to fewer than 100, which is even fewer than that reported for yeast. Consistent with its unique phylogenetic position, smallRNAsequencing revealed 29 Spirodela‐specific microRNA, with only two being shared withElaeis guineensis(oil palm) andMusa balbisiana(banana). CombiningDNAmethylation data and smallRNAsequencing enabled the accurate prediction of 20.5% long terminal repeats (LTRs) that doubled the previous estimate, and revealed a high Solo:IntactLTRratio of 8.2. Interestingly, we found that Spirodela has the lowest globalDNAmethylation levels (9%) of any plant species tested. Taken together our results reveal a genome that has undergone reduction, likely through eliminating non‐essential protein coding genes,rDNAandLTRs. In addition to delineating the genome features of this unique plant, the methodologies described and large‐scale genome resources from this work will enable future evolutionary and functional studies of this basal monocot family.