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Rhizanthes is a holoparasitic plant of the Rafflesiaceae, and, just like Rafflesia, its host is Tetrastigma (Vitaceae). Unlike Rafflesia, very little research has been conducted on Rhizanthes other than a few studies focusing on its taxonomy and anatomy, and limited studies on its propagation, despite some ethnomedicinal uses in several regions of Indonesia. Wild populations of Rhizanthes are declining due to deforestation and overharvesting by locals. Artificial pollination and possible seed spread, which are similar to Rafflesia, may be useful for future propagation-based studies, which are generally very difficult and challenging for members of the Rafflesiaceae. This paper emphasizes the cultural and ethnomedicinal importance of Rhizanthes and seeks to define a conservation road-map that incorporates a scientifically-based approach to research while also seeking a four-pronged approach to the conservation of Rhizanthes: 1) conventional and biotechnology-based conservation; 2) germplasm multiplication and preservation; 3) reintroduction into the wild and conservation of wild populations; 4) policy-based protective measures. Keywords Biotechnology * Conservation * Ethnobotany * Holoparasite * In vitro propagation * Parasitic plant, Introduction Rhizanthes belongs to the Rafflesiaceae, alongside Rafflesia and Sapria (Meijer, 1997). The plant also holoparasitizes some species of Tetrastigma (Banziger & Hansen, 2000). Unlike Rafflesia, Rhizanthes has not been [...]

Rafflesia produces the largest single flowers in the world, at the expense of its host vine, Tetrastigma, yet it begins as an inconspicuous endophyte. It is unknown how the Rafflesia seed gets into the host and germinates. Multiple locals claim to have successfully grown the holoparasitic flower from seeds resulting in blooms. Using available morpho-histological studies, combined with descriptions from local Rafflesia seed growers, as well as unpublished details of our own work, we filled in the missing details of Rafflesia's life cycle from seed germination to endophyte inside the host before it transitions to its flowering stage. Post-germination, the Rafflesia endophyte forms a clonal network of vegetative meristematic cells, separated by the dividing host tissue, each meristematic cell cluster eventually developing into the primordial floral bud or protocorm. We propose future work involving mass spectrometry imaging to characterize the metabolites that allow communication between distant endophytic clusters and floral bud induction without destroying the histology of the sample. Keywords Rafflesiaceae * Holoparasite * Parasitic plant * Plant development, Introduction Rafflesia produces the largest single flowers in the world, growing up to a meter in diameter, at the expense of its host plant, Tetrastigma (Vitaceae). Restricted to the fast [...]

Rafflesia is an endangered endophytic holoparasitic plant that lives the majority of its life inside the tissues of its sole plant host, Tetrastigma. Rafflesia floral buds emerge to produce the world's largest single flower. Like other plants, holoparasites harbor a diverse microbiome, the role(s) of which has remained largely unstudied. We characterized the bacterial microbiome of seeds of Rafflesia speciosa and cuttings of its host. We found evidence that R. speciosa seed has similar bacterial profiles to its infected host, which suggests that seeds sequester certain host bacteria, as well as acquire unique bacterial taxa from biotic associates of the fruit. We did not find evidence of mycorrhizal taxa in the microbiome. This is the first study of the microbial endophytes associated with any Rafflesia species and its host, a tripartite holobiont, and provides insights on its cryptic microbial partners. We discuss how this may aid horticultural propagation of Rafflesia. [ABSTRACT FROM AUTHOR]

As a result of its domestication, breeding and subsequent commercialization, African violet (Saintpaulia ionantha H. Wendl.) has become the most famous and popular Saintpaulia species. There is interest in producing cultivars that have increased resistance to pests and low temperature, in the introduction of novel horticultural characteristics such as leaf shape, flower colour, size and form, and in improved productivity and enhanced flower duration in planta. In African violet, techniques such as the application of chemical mutagens (ethylmethanesulfonate, N-nitroso-N-methylurea), radiation (gamma (γ)-rays, X-rays, carbon ion beams) and colchicine have been successfully applied to induce mutants. Among these techniques, γ radiation and colchicine have been the most commonly applied mutagens. This review offers a short synthesis of the advances made in African violet breeding, including studies on mutation and somaclonal variation caused by physical and chemical factors, as well as transgenic strategies using Agrobacterium-mediated transformation and particle bombardment. In African violet, Agrobacterium-mediated transformation is affected by the Agrobacterium strain, selection marker, and cutting-induced wounding stress. Somaclonal variation, which arises in tissue cultures, can be problematic in maintaining true-to-type clonal material, but may be a useful tool for obtaining variation in flower colour. The only transgenic African violet plants generated to date with horticulturally useful traits are tolerant to boron (heavy metal) stress, or bear a glucanase-chitinase gene.

RNA-ligand docking is a part of computational biology, which is currently lowly recognized compared to the protein-ligand docking procedure commonly applied for drug discovery. This in silico study aims to create a simplified protocol for RNA-ligand docking, which is applicable to RNA-targeting small molecular drug screening. Four alkaloids (berberine, colchicine, nicotine, and tomatine) were subjected to this study and contended against the SARS-CoV-2 genomic RNA -1 PRF component targeting control drug, merafloxacin, including two known intercalator berberine and colchicine, a small alkaloid nicotine and a large alkaloid tomatine. The alkaloids were screened for drug-likeness properties (Lipinski’s Rules of 5 or LRo5), bioavailability indexes, and synthetic accessibility values using SwissADME before docking. The docking used PyRx – Autodock Vina and re-scored for RNA-ligand scoring using AnnapuRNA. The docking results have the interactions mapped using fingeRNAt and visualized using Discovery Studio. Molecular dynamics using CHARMM36 and AMBER forcefields were simulated in NAMD. The molecular dynamics 1 ns simulation results showed that the ligand interaction over time did not cause much interference with the RNA, indicated by the low number of RMSD changes between RNA itself and the RNA-ligand complex. Additionally, CHARMM36 forcefield provided more stable fluctuation compared to AMBER. The results indicated that tomatine disobeyed LRo5 and had a low bioavailability index and bad synthetic accessibility value, while the rest alkaloids passed. In the end, berberine has an even higher docking score than the control drug. The study also shows that this protocol can be useful for future RNA-ligand computational studies. [ABSTRACT FROM AUTHOR]

This study is the first report on the distribution of Rhipsalis baccifera (J.S.Muell) Stearn in Bandung, West Java, Indonesia. R. baccifera is an epiphyte cactus that generally grows on the vertical substrate of tree barks. The distribution of R. baccifera was examined by tagging the tree hosts using a global positioning system (GPS). Additionally, the organs and growth stages of the cactus, as well as the interactions of the cactus with the host plants, were photographed. The results show that R. baccifera is distributed unevenly in Bandung, as the population density is higher in the northern area of the city than in the south. This uneven distribution suggests that frugivorous birds and human activities in the area play an important role in the distribution of R. baccifera. The cactus has spines during its early stage, which is greatly reduced upon reaching its mature stage. However, within the same region, the cactus appears to selectively grow on specific hosts, mainly on trees with rough barks or grown by moss. In Bandung, the cactus is mostly found growing on mahogany trees (Swietenia macrophylla King). Not all trees adjacent to the host trees have the cactus growing on them, which further suggests the cactus' preference for specific host trees. [ABSTRACT FROM AUTHOR]

In this research, we compared the anatomy and biomechanics of two species of mudskipper vs an aquatic sandgoby in view of terrestrial locomotion. Of particular interest was the relationship (if any) of pectoral fin movement with pelvic fin movement. We show that the pelvic fins of the terrestrial mudskippers studied herein, are retractable and move antagonistically with the pectoral fins. The pelvic fin of the sandgoby studied here is contrarily non-retractable and drags on any underlying substrate that the sandgoby tries to crawl across. We find that the pelvic and pectoral fin muscles of all fish are separated, but that the pectoral fins of the mudskipper species have bulkier radial muscles than the sandgoby. By coupling a detailed morphological investigation of pectoral-pelvic fins musculature with finite element simulations, we find that unlike sandgobies, the mudskipper species are able to mechanically push the pelvic fins downward as pectoral fins retract. This allows for an instant movement of pelvic fins during the pectoral fin backward stroke and as such the pelvic fins stabilize mudskippers through Stefan attachment of their pelvic fins. This mechanism seems to be efficient and energy saving and we hypothesize that the piston-like action might benefit pelvic–pectoral fin antagonism by facilitating a mechanical down-thrust. Our research on the biomechanics of tree-climbing fish provides ideas and greater potential for the development of energetically more efficient systems of ambulation in biomimetic robots. [ABSTRACT FROM AUTHOR]

As a result of its domestication, breeding and subsequent commercialization, African violet (Saintpaulia ionantha H. Wendl.) has become the most famous and popular Saintpaulia species. There is interest in producing cultivars that have increased resistance to pests and low temperature, in the introduction of novel horticultural characteristics such as leaf shape, flower colour, size and form and in improved productivity and enhanced flower duration in planta. In African violet, techniques such as the application of chemical mutagens (ethylmethanesulfonate, N-nitroso-N-methylurea), radiation (gamma (γ)-rays, X-rays, carbon ion beams) and colchicine have been successfully applied to induce mutants. Among these techniques, γ radiation and colchicine have been the most commonly applied mutagens. This review offers a short synthesis of the advances made in African violet breeding, including studies on mutation and somaclonal variation caused by physical and chemical factors, as well as transgenic strategies using Agrobacterium-mediated transformation and particle bombardment. In African violet, Agrobacterium-mediated transformation is affected by the Agrobacterium strain, selection marker and cutting-induced wounding stress. Somaclonal variation, which arises in tissue cultures, can be problematic in maintaining true-to-type clonal material, but may be a useful tool for obtaining variation in flower colour. The only transgenic African violet plants generated to date with horticulturally useful traits are tolerant to boron (heavy metal) stress, or bear a glucanase-chitinase gene. [ABSTRACT FROM AUTHOR]

This study provides a hypothetical discussion about the growth of Rafflesia patma Blume (syn. R. horsfieldii R. Br. (1821); Rafflesiaceae), an endophytic parasite, within a grafted host, a woody vine (Tetrastigma leucostaphylum (Dennst.) Alston). Based on the observation of a 10-year old (2007 to 2017) R. patma -- T. leucostaphylum graft, we hypothesize that R. patma moves away from its host rather than remaining in an anchored position from which it flowers, although flower knobs that emerge later may vary in range from the grafting point, i.e., flower knobs may develop close to or far away from the grafting point. Our provisional macroscopic observations point towards a gradual creeping motion of the endophyte towards new host tissues, flowering opportunistically when sufficient nutrients have been found. Much has yet to be discovered about the growth and flowering behavior of R. patma and about the dynamics of the R. patma -- T. leucostaphylum interaction. [ABSTRACT FROM AUTHOR]

African violet (Saintpaulia ionantha H. Wendl.) has been domesticated, bred and commercialized. It is the most famous and popular of the Saintpaulia species, its ornamental value arising from its attractive leaves and flowers. African violet plants are easy to propagate by adventitious organ regeneration and are very sensitive to environmental factors including light, temperature, humidity, CO2 concentration and photoperiod. This review offers a short synthesis on advances made in conventional vegetative propagation by adventitious organ regeneration, select early historical in vitro developmental perspectives, and vegetative and reproductive development of African violet. [ABSTRACT FROM AUTHOR]

Bioprinting is a technical innovation that has revolutionized tissue engineering. Using conventional printer cartridges filled with cells as well as a suitable scaffold, major advances have been made in the biomedical field, and it is now possible to print skin, bones, blood vessels, and even organs. Unlike animal systems, the application of bioprinting in simple plant tissue cells is still in a nascent phase and has yet to be studied. One major advantage of plants is that all living parts are reprogrammable in the form of totipotent cells. Plant bioprinting may improve scientists'understanding of plant shape and morphogenesis, and could serve for the mass production of desired tissues or plants, or even the production of plant-based biomaterial for industrial uses. This perspectives paper explores these possibilities using knowledge on what is known about bioprinting in other biosystems. [ABSTRACT FROM AUTHOR]