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Background Maize (Zea mays L.) is at the vanguard facing the upcoming breeding challenges. However, both a super pan-genome for the Zea genus and a comprehensive genetic variation map for maize breeding are still lacking. Results Here, we construct an approximately 6.71-Gb pan-Zea genome that contains around 4.57-Gb non-B73 reference sequences from fragmented de novo assemblies of 721 pan-Zea individuals. We annotate a total of 58,944 pan-Zea genes and find around 44.34% of them are dispensable in the pan-Zea population. Moreover, 255,821 common structural variations are identified and genotyped in a maize association mapping panel. Further analyses reveal gene presence/absence variants and their potential roles during domestication of maize. Combining genetic analyses with multi-omics data, we demonstrate how structural variants are associated with complex agronomic traits. Conclusions Our results highlight the underexplored role of the pan-Zea genome and structural variations to further understand domestication of maize and explore their potential utilization in crop improvement.

A New Antibiotic, Antimycin A 9 , Produced by Streptomyces sp. K01-0031. -Compound (I) shows strong nematocidal and insecticidal activity. -(SHIOMI*, K.; HATAE, K.; HATANO, H.; MATSUMOTO, A.; TAKAHASHI, Y.; JIANG, C.-L.; TOMODA, H.; KOBAYASHI, S.; TANAKA, H.; OMURA, S.; J. Antibiot. 58 (2005) 1, 74-78; Sch. Pharm. Sci., Kitasato Univ., Minato, Tokyo 108, Japan; Eng.) -C. Oppel 29-207

Maize is a globally valuable commodity and one of the most extensively studied genetic model organisms. However, we know surprisingly little about the extent and potential utility of the genetic variation found in the wild relatives of maize. Here, we characterize a high-density genomic variation map from ~700 genomes encompassing maize and all wild taxa of the genus Zea, identifying over 65 million single nucleotide polymorphisms (SNPs), 8 million Insertion/Deletion (InDel) polymorphisms, and over one thousand novel inversions. The variation map reveals evidence of selection within taxa displaying novel adaptations such as perenniality and regrowth. We focus in detail on evidence of convergent adaptation in highland teosinte and temperate maize. This study not only indicates the key role of hormone related pathways in highland adaptation and flowering time related pathways in high latitude adaptation, but also identifies significant overlap in the genes underlying adaptations to both environments. To show how this data can identify useful genetic variants, we generated and characterized novel mutant alleles for two flowering time candidate genes. This work provides the most extensive sampling to date of the genetic diversity inherent in the genus Zea, resolving questions on evolution and identifying adaptive variants for direct use in modern breeding.