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Summary: Arabis alpina is a polycarpic perennial, in which PERPETUAL FLOWERING1 (PEP1) regulates flowering and perennial traits in a vernalization‐dependent manner. Mutagenesis screens of the pep1 mutant established the role of other flowering time regulators in PEP1‐parallel pathways.Here we characterized three allelic enhancers of pep1 (eop002, 085 and 091) which flower early. We mapped the causal mutations and complemented mutants with the identified gene. Using quantitative reverse transcriptase PCR and reporter lines, we determined the protein spatiotemporal expression patterns and localization within the cell. We also characterized its role in Arabidopsis thaliana using CRISPR and in A. alpina by introgressing mutant alleles into a wild‐type background.These mutants carried lesions in an AAA+ ATPase of unknown function, FLOWERING REPRESSOR AAA+ATPase 1 (AaFRAT1). AaFRAT1 was detected in the vasculature of young leaf primordia and the rib zone of flowering shoot apical meristems. At the subcellular level, AaFRAT1 was localized at the interphase between the endoplasmic reticulum and peroxisomes. Introgression lines carrying Aafrat1 alleles required less vernalization to flower and reduced number of vegetative axillary branches. By contrast, A. thaliana CRISPR lines showed weak flowering phenotypes.AaFRAT1 contributes to flowering time regulation and the perennial growth habit of A. alpina. [ABSTRACT FROM AUTHOR]

Dormancy has evolved in plants to restrict germination to favourable growth seasons. Seeds from most crop plants have low dormancy levels due to selection for immediate germination during domestication. Seed dormancy is usually not completely lost and low levels are required to maintain sufficient seed quality. Brassica napus cultivars show low levels of primary seed dormancy. However, B. napus seeds are prone to the induction of secondary dormancy, which can lead to the occurrence of volunteers in the field in subsequent years after cultivation. The DELAY OF GERMINATION 1 (DOG1) gene has been identified as a major dormancy gene in the model plant Arabidopsis thaliana. DOG1 is a conserved gene and has been shown to be required for seed dormancy in various monocot and dicot plant species. We have identified three B. napus genes with high homology to AtDOG1, which we named BnaA.DOG1.a, BnaC.DOG1.a and BnaC.DOG1.b. The transcripts of these genes could only be detected in seeds and showed a similar expression pattern during seed maturation as AtDOG1. In addition, the BnaDOG1 genes showed enhanced transcript levels after the induction of secondary dormancy. These results suggest a role for DOG1 in the induction of secondary dormancy in B. napus. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is one of the most important crops with a worldwide production of 370 million metric tons. The objectives of this study were (1) to create a high-quality consensus sequence across the two haplotypes of a diploid clone derived from a tetraploid elite variety and assess the sequence divergence from the available potato genome assemblies, as well as among the two haplotypes; (2) to evaluate the new assembly's usefulness for various genomic methods; and (3) to assess the performance of phasing in diploid and tetraploid clones, using linked-read sequencing technology. We used PacBio long reads coupled with 10x Genomics reads and proximity ligation scaffolding to create the dAg1_v1.0 reference genome sequence. With a final assembly size of 812 Mb, where 750 Mb are anchored to 12 chromosomes, our assembly is larger than other available potato reference sequences and high proportions of properly paired reads were observed for clones unrelated by pedigree to dAg1. Comparisons of the new dAg1_v1.0 sequence to other potato genome sequences point out the high divergence between the different potato varieties and illustrate the potential of using dAg1_v1.0 sequence in breeding applications., (© The Author(s) 2021. Published by Oxford University Press on behalf of Genetics Society of America.)