Chromosome-scale genome assembly of Eustoma grandiflorum, the first complete genome sequence in family Gentianaceae

Eustoma grandiflorum (Raf.) Shinn., is an annual herbaceous plant native to the southern United States, Mexico, and the Greater Antilles. It has a large flower with a variety of colors and an important flower crop. In this study, we established a chromosome-scale de novo assembly of E. grandiflorum by integrating four genomic and genetic approaches: (1) Pacific Biosciences (PacBio) Sequel deep sequencing, (2) error correction of the assembly by Illumina short reads, (3) scaffolding by chromatin conformation capture sequencing (Hi-C), and (4) genetic linkage maps derived from an F2 mapping population. The 36 pseudomolecules and unplaced 64 scaffolds were created with total length of 1,324.8 Mb. Full-length transcript sequencing was obtained by PacBio Iso-Seq sequencing for gene prediction on the assembled genome, Egra_v1. A total of 36,619 genes were predicted on the genome as high confidence HC) genes. Of the 36,619, 25,936 were annotated functions by ZenAnnotation. Genetic diversity analysis was also performed for nine commercial E. grandiflorum varieties bred in Japan, and 254,205 variants were identified. This is the first report of the construction of reference genome sequences in E. grandiflorum as well as in the family Gentianaceae.

Double Mutant Analysis with the Large Flower Mutant, ohbana1, to Explore the Regulatory Network Controlling the Flower and Seed Sizes in Arabidopsis thaliana

Two growth processes, cell proliferation and expansion, determine plant species-specific organ sizes. A large flower mutant in Arabidopsis thaliana, ohbana1 (ohb1), was isolated from a mutant library. In the ohb1 flowers, post-mitotic cell expansion and endoreduplication of nuclear DNA were promoted. The whole-genome resequencing and genetic analysis results showed that the loss of function in MEDIATOR16 (MED16), a mediator complex subunit, was responsible for the large flower phenotypes exhibited by ohb1. A phenotypic analysis of the mutant alleles in MED16 and the double mutants created by crossing ohb1 with representative large flower mutants revealed that MED16 and MED25 share part of the negative petal size regulatory pathways. Furthermore, the double mutant analyses suggested that there were genetically independent pathways leading to cell size restrictions in the floral organs which were not related to the MED complex. Several double mutants also formed larger and heavier seeds than the wild type and single mutant plants, which indicated that MED16 was involved in seed size regulation. This study has revealed part of the size-regulatory network in flowers and seeds through analysis of the ohb1 mutant, and that the size-regulation pathways are partially different between floral organs and seeds.

The synstigma turns the fig into a large flower

The synstigma is a structure formed by clusters of two to several stigmas, whether in the same or between different flowers. Although rare in angiosperms, synstigmas are found in c. 500 out of the c. 750 Ficus spp. (Moraceae). This floral structure is associated with fig-fig wasp pollinating mutualism. The synstigma structure and pollen tube pathways were studied in six Ficus spp. from Ficus section Americanae to test the hypothesis that the synstigma allows pollen grains deposited on a stigma to emit pollen tubes that can grow laterally and fertilize surrounding flowers. Syconia containing recently pollinated stigmas were collected and dissected, and the stigmas were processed for analyses with light and scanning and transmission electron microscopy. The arrangement of the synstigmas across species can be spaced or congested, with the number of stigmas per synstigma ranging from two to 20. Contact between the stigmas in a synstigma occurs by the intertwining of the stigmatic branches and papillae; their union is firm or loose. The pollen tube grows through live cells of the transmitting tissue until reaching the ovule micropyle. Curved pollen tubes growing from one stigma to another were observed in five out of the six species studied. The curvilinear morphology of pollen tubes probably results from competition by pollen between the stigmas composing a synstigma via chemotropic signals. The synstigma appears to be a key adaptation that ensures seed production by flowers not exploited by the fig wasps in actively pollinated Ficus spp.

First inclusion of a trichiine beetle (Coleoptera: Scarabaeidae) from Baltic amber

Baltic amber forms the largest known Konservat-Lagerstätte of fossil plant resin and the richest repository of fossil insects of any age on Earth. Despite a long history of palaeobiological research of Baltic amber (over 200 years) and really intensive taxonomic study in the last decade, many interesting and new bioinclusions await scientific attention. In the current paper, the brief report of an unique large flower chafer inclusion from the Early Tertiary Baltic amber is provided. The author decided not to formally create a new genus and not to subjectively assign the Eocene beetle to an extant genus. However, the specimen seems to be remarkable and surprising in different aspects. The reported Eocene beetle is: 1) one of the oldest members of the subfamily Cetoniinae and also the earliest fossil record of the tribe Trichiini; 2) the first known representative of the subfamily in Baltic amber; 3) the largest known beetle fossilized in amber; and 4) an unique example of mineralized fossil included in amber.

Chapter V

Meanwhile, the sun was warming the main door of the church. Golden flies were buzzing around a large flower growing between two of the steps in front of the door. Feeling a little dazed, Abbé Mouret was just deciding to move on when the...

Isolation of Flower Development Regulator Gene SEPALLATA 1 in Phalaenopsis amabilis (L.) Blume

<p class="Els-Abstract-text"><em>Phalaenopsis amabilis </em>(L.) Blume<em> </em>is an indigenous orchid species in Indonesia. This orchid has a white large flower. The large flower is caused by the existence of gene that has an important role in flower development. One of the genes is <em>SEPALLATA 1. </em>This gene is a member of superfamily MADS-Box gene. <em>SEPALLATA 1 </em>gene is a marker of primordial flower organ. This study aimed to isolate <em>SEPALLATA1</em><em> </em>gene from <em>Phalaenopsis amabilis </em>(L.) Blume by PCR using forward primer 5’-GCT-GGA-GCG-GAT-CGA-GAA-CA-3’and reverse primer 5’-TCA-TGC-AAG-CCA-ACC-AGG-TG-3’<em>. </em>This study successfully amplified 691 bp lengths of <em>SEPPALATA1</em> fragment, lacking 20 bp upstream which consist its start codon.</p><p> </p><div><p class="Els-keywords"><strong>Keywords:</strong> Flower development regulation, <em>Phalaenopsis amabilis</em> (L.) Blume, SEPALLATA 1 gene.</p></div>

Epimedium xichangense (Berberidaceae), a new species from Sichuan, China

A new species of Epimedium L. (Berberidaceae), E. xichangense Y. J. Zhang, is described and illustrated from Xichang, Sichuan Province, China. E. xichangense has large flower with petals bearing long spurs and obvious basal lamina, and should be a member of ser. Davidianae. The species is easily distinguished from other species of ser. Davidianae by its compact rhizome, leaflet number and morphology, leaf number and arrangement on the flowering stem, flower color, and shape and size of inner sepal and petal. Epimedium xichangense is most similar to E. elongatum of ser. Dolichocerae in morphology, but they can be differentiated clearly by the flower and rhizome characters.