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  • Author: Jaime A. Teixeira da Silva x
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Abstract

Synthetic seed were produced from protocorm-like bodies (PLBs) of hybrid Cymbidium Twilight Moon ‘Day Light’ after culture on a new medium, Teixeira Cymbidium (TC) medium. This new medium contained, in addition to a unique selection of macro- and micronutrients, 0.1 mg/l α-naphthaleneacetic acid and 0.1 mg/l kinetin, 2 g/l tryptone and 20 g/l sucrose, and was solidified with 8 g/l Bacto agar. Several explant types and sizes (intact PLBs, half-PLBs, PLB longitudinal thin cell layers) were tested. In addition, pretreatment of PLB-synseeds with 200 mM KNO3 solution, the addition of activated charcoal or coconut water to synseeds, light vs dark culture, short-term (1 month) and long-term (6 and 12 months) low-temperature (4°C) storage, as well as cryostorage were also tested. All treatments resulted in less PLBs than the control treatment. Among all these treatments, only the use of TC medium or incorporation of coconut water into synseeds resulted in “germination” while lowtemperature storage (1-6 months) was only possible under liquid TC. These results would allow for the short-term preservation of Cymbidium germplasm but not for effective cryopreservation.

Abstract

High frequency protocorm-like body (PLB) production from hybrid Cymbidium Twilight Moon ‘Day Light’ has been developed through a new medium, Teixeira Cymbidium (TC) medium. Two new TC media containing variable amounts of macroand micronutrients and other additives, inspired by Winarto and Teixeira (WT) medium for Anthurium and Murashige and Skoog (MS) basal medium were used to induce PLBs and callus. Control medium was research- and industry-standard Vacin and Went (VW) medium. The first TC medium, TCPLB, could induce significantly more PLBs than on VW while high levels of macronutrients in the second TC medium, TCCALLUS, and MS were required to induce callus. All PLB induction media contained 0.1 mg/l α-naphthaleneacetic acid (NAA) and 0.1 mg/l kinetin (KIN), 2 g/l tryptone and 20 g/l sucrose, and solidified with 8 g/l Bacto agar while callusinduction media were identical, except that KIN was substituted by thidiazuron (TDZ). Basal medium had a significant effect on PLB and callus formation. This protocol could be used to induce PLBs and callus from other Cymbidium species or cultivars.

Abstract

In publishing ethics, self-plagiarism or text recycling is subject to a correction or retraction. This paper examines a high-profile case of ethical exceptionalism in the publishing status quo. Jennifer Couzin-Frankel, a science writer for the magazine Science, published by The American Association for the Advancement of Science (AAAS), was the first reporter to publicly reveal the identity of Brandon Stell, the President of The PubPeer Foundation, which owns PubPeer, a science whistle-blower website. The AAAS is a Committee on Publication Ethics (COPE) member publisher. Couzin-Frankel published two articles, one of which self-plagiarized (i.e., the use of text written by the same person but not properly cited, or acknowledged) about 25% of text in the other article. Couzin-Frankel has also employed nested self-citation, which is the citation of a separate part of a paper such as a table or text box, to give the impression of a separate publication. These aspects call into question how strictly information is vetted and edited at AAAS’s Science. Despite alerting the AAAS, this heavily self-plagiarized paper has not been corrected or retracted. How then do the AAAS and COPE justify the continued publication of both texts?

Abstract

ResearchGate (RG) is one of the most popular academic social media platforms currently available to scientists. Allowing scientists, researchers and academics (SRAs) to network through the creation of a free account. RG provides a virtually unlimited ability for SRAs to share research, contact each other through an integrated platform and share ideas. In recent times, projects have been increasing in scope and visibility, fortifying the RG network status. This paper examines some of the project-related features at RG and points out, within a wider examination of RG and other SRA-oriented academic social media platforms, the existing benefits and risks. The results of this work will allow SRAs to manage and invest their time in a better way.

Abstract

Science is becoming more challenging, not only for scientists, but also for editors and publishers. Faced with limited funding within an expanding economic crisis, competition between scientists is increasing. The struggle for professional survival is leading some to revert to dishonest tactics to get ahead of the pack and cheating or fraud may be involved. Confronted with these new realities, which have become more debatable within the public arena, mainly as a result of an increase in blogs and social media, editors and publishers are reinforcing current publishing platforms in a bid to reduce the risks and to fortify their journals against future submission- and fraud-related problems. Ultimately, this places greater scrutiny — and stress — on the authorship, leading to an increase in militarization. At some point — which certain hints already indicate — the criminalization of science will begin as publishers fail to curtail fraud.

Abstract

In this opinion piece, some of the practices of academic publication in the biomedical field related to the rewarding, or the lack thereof, of peer reviewers are described and discussed. The role and possibly exploitative relationship of mainstream, established publishers of prestigious journals towards their contributors (authors), and peer reviewers is considered. In addition, the role and accountability of publishers and contributors in “predatory” journals is assessed. Professionals who are recruited by the publishing industry, especially the for-profit industry, either as peer reviewers or editors, to complete a professional task, should be rewarded financially as professionals, as for other sectors of the economy, and not simply exploited for free. Points systems or discounts off a publisher’s products do not constitute sufficient, or fair, compensation.

Abstract

Bauhinia species (including B. acuminata, B. variegata, B. purpurea, B. monandra, B. galpinii, B. blakeana and B. acuminata) are popular ornamental plants, usually woody ornamentals or herbaceous lianas, with attractive flowers typical of the Leguminosae of arid, temperate, sub-tropical and tropical zones. Bauhinia species also serve as fodder and many have multiple medicinal and biological properties. There is an interest in commerce and amongst collectors to clonally propagate species from this genus. This review highlights protocols that currently exist for the in vitro culture of Bauhinia species as a means to clonally propagate material.

Abstract

Only few studies in the plant tissue culture literature have examined the impact of lanthanoids, or rare earth elements, on in vitro plant organogenesis. In this study, using a model plant, hybrid Cymbidium Twilight Moon ‘Day Light’, the impact of six lanthanoids (lanthanum (III) nitrate hexahydrate (La(NO3)3 · 6H2O), cerium (III) nitrate hexahydrate (Ce(NO3)3 · 6H2O), neodymium (III) nitrate hexahydrate (Nd(NO3)3 · 6H2O), praseodymium (III) nitrate hexahydrate (Pr(NO3)3 · 6H2O), samarium (III) nitrate hexahydrate (Sm(NO3)3 · 6H2O), gadolinium (III) nitrate hexahydrate (Gd(NO3)3 · 6H2O) on new protocorm-like body (neo-PLB) formation on Teixeira Cymbidium (TC) medium was examined. 0 (control), 1, 2, 4 and 8 mg·dm-3 of each lanthanoid was tested. All lanthanoids could produce more neo-PLBs and neo-PLB fresh weight than TC medium lacking plant growth regulators (PGRs), suggesting some PGR-like ability of lanthanoids, although PLB-related traits (percentage of half-PLBs forming neo-PLBs; number of neo-PLBs formed per half-PLB; fresh weight of half-PLB + neo-PLBs) was always significantly lower than TC medium containing PGRs. Except for Gd, all other lanthanoids had no negative impact on the number of new leaves from neo-PLB-derived shoots, but all lanthanoids showed a significantly lower plant height, shoot fresh weight and shoot dry weight and, in most cases, SPAD (chlorophyll content) value. In addition, using the same concentration of the six lanthanoids, the ability to fortify root formation of neo-PLB-derived plantlets was also assessed. Except for Sm, all other lanthanoids significantly increased the number of roots, root fresh and dry weight.

Abstract

Only few studies in the plant tissue culture literature have examined the impact of filter paper on in vitro plant organogenesis. In this study, using a model plant, hybrid Cymbidium Twilight Moon ‘Day Light’, the impact of a single or double layer of Advantec #2 or Whatman #1 filter paper on new protocorm-like body (neo-PLB) formation on Teixeira Cymbidium (TC) medium was examined for half-PLBs (transgenic and non-transgenic), PLB-derived transverse thin cell layers (tTCLs), and PLB synseeds. In addition, the response of half-PLBs or tTCLs to two antibiotics (kanamycin and cefotaxime, commonly used in plant genetic transformation studies) was investigated either directly on gelled medium or on filter paper-overlaid medium. Filter paper negatively affected most growth and developmental parameters of all the explants tested, both transgenic and non-transgenic. A double sheet of filter paper had a significantly (P ≤ 0.05) more negative impact than a single sheet, relative to the control values (i.e., no filter paper). Kanamycin inhibited neo-PLB formation on TC medium, the negative impact being greater on a single layer than on a double layer of filter paper, i.e., filter paper buffered the growth-inhibiting characteristics of kanamycin. Up to 100 mg/l, cefotaxime showed no apparent negative effects on neo-PLBs formation and growth, although hyperhydricity was observed when filter paper was not used.

Abstract

Teixeira da Silva J.A., 2014: Novel factors affecting shoot culture of chrysanthemum (Dendranthema × grandiflora) [Alternatyvių standiklių, skystų terpės priedų, CO2 sodrinimo ir kitų faktorių įtaka chrizantemų (Dendranthema × grandiflora (Ramat.) Kitamura) ūglių kultūrų auginimui]. - Bot. Lith., 20(1): 27-40.

Chrysanthemum (Dendranthema × grandiflora (Ramat.) Kitamura) continues to be one of the most important ornamental plants in the world. Although the tissue culture of chrysanthemum has been widely explored, several unexplored topics remain, and, in developing countries, there is always the constant search for reducing the cost of raising tissue cultured plants. In this study, by focusing on a leading market cultivar in Japan, ‘Shuhouno- chikara’, alternatives to agar (as the gelling agent) and sucrose (as the carbon source) for chrysanthemum tissue culture were sought. Both Gellan gum and agar resulted in greater shoot and root production than all other gelling agents tested, including Bacto agar, phytagel, oatmeal agar, potato dextrose agar, barley starch and corn starch. All of the alternative liquid-based medium additives tested (low and full fat milk, Coca-cola ®, coffee, Japanese green, Oolong and Darjeeling teas) negatively impacted plant growth, stunted roots and decreased chlorophyll content (SPAD value) of leaves. There was no difference between plants grown on medium with refined sucrose or table sugar, although poor growth was observed when stevia (Stevia rebaudiana) extract was used. Photoautotrophic micropropagation increased significantly the shoot mass relative to control plants, even when the density of plants was doubled. Aeration improved plantlet growth. The tetrazolium test was a simple, but effective essay to see the intensity and strength of root growth in different basal media. MDH activity decreased in the root+shoot extract of plants grown on most alternative media, but remained high on TCSGM (Teixeira’s chrysanthemum shoot growth medium), Gellan gum, aerated and CO2-enriched cultures. A similar trend was observed for deaminating GDH, while an opposite trend was observed for aminating GDH activity. These experiments indicate that tissue culture research for chrysanthemum still provides a rich field for exploration with interesting and valuable results