The red bayberry genome and genetic basis of sex determination

Abstract

Morella rubra, red bayberry, is an economically important fruit tree in south China. Here, we assembled the first high-quality genome for both a female and a male individual of red bayberry. The genome size was 313-Mb, and 90% sequences were assembled into eight pseudo chromosome molecules, with 32 493 predicted genes. By whole-genome comparison between the female and male and association analysis with sequences of bulked and individual DNA samples from female and male, a 59-Kb region determining female was identified and located on distal end of pseudochromosome 8, which contains abundant transposable element and seven putative genes, four of them are related to sex floral development. This 59-Kb female-specific region was likely to be derived from duplication and rearrangement of paralogous genes and retained non-recombinant in the female-specific region. Sex-specific molecular markers developed from candidate genes co-segregated with sex in a genetically diverse female and male germplasm. We propose sex determination follow the ZW model of female heterogamety. The genome sequence of red bayberry provides a valuable resource for plant sex chromosome evolution and also provides important insights for molecular biology, genetics and modern breeding in Myricaceae family.

The genome of kenaf (Hibiscus cannabinus L.) provides insights into bast fibre and leaf shape biogenesis

“…With the development of sequencing technology, more and more species completed the whole-genome sequencing, such as P. betuleafolia (Dong et al, 2019), P. granatum (Yuan et al, 2018) and M. rubra (Jia et al, 2019). We generated the first highquality chromosomal level genome assembly of H. cannabinus var.…”

The pomegranate (Punica granatum L.) draft genome dissects genetic divergence between soft‐ and hard‐seeded cultivars

“…() subsequently released the ‘Taishanhong’ pomegranate genome, which resolved the previously debated taxonomic status of the genus Punica, and reclassified it in the family Lythraceae. These two genomes enabled certain advances in comparative and evolutionary genomics studies (Jia et al ., ; Qin et al ., ; Yuan et al ., ; Zhao et al ., ). However, these resources are fragmented, and almost of all of the scaffolds or contigs are arbitrarily ordered and oriented.…”

Construction of an anchoring SSR marker genetic linkage map and detection of a sex-linked region in two dioecious populations of red bayberry

“…To construct a genetic linkage map, 95 F1 progeny and 127 SSR markers that were heterozygous in 'Biqi', 'Dongkui-male' or both were selected. The MrFT2_BD-SEX marker, which was developed from the femalespecific region 15 and exhibited different fragments between the parents 'Biqi' and 'Dongkui-male', was also included. Based on the published biparental genetic linkage map of red bayberry 15 , we then estimated a new integrated high-density SSR-SNP linkage map ( Fig.…”

“…The MrFT2_BD-SEX marker, which was developed from the femalespecific region 15 and exhibited different fragments between the parents 'Biqi' and 'Dongkui-male', was also included. Based on the published biparental genetic linkage map of red bayberry 15 , we then estimated a new integrated high-density SSR-SNP linkage map ( Fig. S1) with 3,073 SNP and 118 SSR markers and MrFT2_BD-SEX, while the nine unmapped SSR markers presented unclear genotypes or distorted segregation ratios.…”

“…As red bayberry is an important fruit in southern China, it is important to study the sex-determination mechanism of this species. Using the assembled genomes of one female and one male individual, we previously proposed a ZW model of sex determination and identified a small (59 Kb) female-specific region at the distal end of chromosome 8 15 . However, the ZW model has not been verified, and how the sex-linked region is inherited remains largely unknown.…”