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Watanawikkit P.,Kasetsart University | Watanawikkit P.,Ramkhamhaeng University | Tantiwiwat S.,Kasetsart University | Bunn E.,Kasetsart University | And 4 more authors.
Botanical Journal of the Linnean Society | Year: 2012

Cryopreservation is an important tool for the exsitu preservation of endangered plants. In this article, we describe the development of a cryopreservation protocol for orchid protocorms using the terrestrial Australian species Caladenia latifolia. Protocorms of C. latifolia generated asymbiotically each month on Murashige and Skoog (MS) medium containing 10μM N6-benzyladenine (BAP) provided explant sources for cryopreservation. Three size classes of protocorms were used as source explant material [small (S, ≤1mm); medium (M, >1<4mm); large (L, ≥4mm)] in combination with five desiccation treatments, i.e. 0, 0.4, 0.6, 0.8 and 1.0M glycerol. After 2days on desiccation medium, protocorms were treated with two cryoprotectant solutions (PVS2 and PVS4 at 0°C for 15, 20, 25 and 30min) before immersion in liquid nitrogen for 1day. Protocorms were then removed from liquid nitrogen storage, warmed rapidly (in a 40°C waterbath) and placed on three recovery media: half-strength MS with 0.5μM BAP, 0.5μM 6-furfurylaminopurine (kinetin) or 0.5μM 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ). Protocorms on recovery media were incubated at 25°C under dark conditions and potential protocorm survival was observed at 60 and 90days using a fluorescein diacetate (FDA) test for protocorm viability. Protocorm survival was correlated significantly with explant size. Large cryopreserved protocorms had the highest potential survival rate (>90%) relative to small (<10%) and medium (70-80%) protocorms. Different desiccation media treatments did not affect significantly the survival percentage (74-92%). Similarly, changing the cryoprotectant solution and time of incubation at 0°C did not affect significantly potential protocorm survival (76-96%). Potential protocorm survival on various recovery media was not significantly different among treatments (88-100% survival). The study indicates that the cryopreservation of terrestrial orchid protocorms is technically feasible and provides a new and potentially highly beneficial tool in terrestrial orchid conservation where seed may be limited (because of species rarity), or as a means of storing and later utilizing the large surpluses of protocorms generated in propagation programmes. © 2012 The Linnean Society of London.

Raskoti B.B.,CAS Institute of Botany | Raskoti B.B.,University of Chinese Academy of Sciences | Jin W.-T.,CAS Institute of Botany | Xiang X.-G.,CAS Institute of Botany | And 6 more authors.
Cladistics | Year: 2016

The first comprehensive phylogenetic study of the orchid genus Herminium and its allies is presented, based on seven molecular markers (nuclear internal transcribed spacer, Xdh, chloroplast matK, psaB, psbA-trnH, rbcL and trnL-F) and 37 morphological characters. Phylogenetic analyses indicate that Herminium as currently delimited is paraphyletic and that several genera are deeply nested within it. Based on parsimony analysis of total evidence, the generic circumscription of Herminium is expanded to include Androcorys, Bhutanthera, Frigidorchis and Porolabium. Apomorphic and plesiomorphic character states are identified for various clades recovered in this study. A few species currently wrongly assigned to Peristylus and Platanthera are here included in Herminium. All necessary new combinations are made. © 2016 The Willi Hennig Society.

Taylor A.,Trace Element Laboratory | Barlow N.,Trace Elements Laboratory | Day M.P.,Australian Wine Research Institute | Hill S.,LCG Group | And 2 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2016

This review covers publications from the second half of 2014 to the middle of 2015. Accounts of As toxicity in Bangladesh from water supplies with naturally high concentrations of As, emerged more than 20 years ago. A review of the research undertaken throughout this entire period has now been presented by those who have been involved throughout this period. Coincidentally, techniques developed for measurement of As and its speciation, in foods and drinking water were also reviewed in detail. Locally derived reference intervals for concentrations of toxic metals in biological fluids were reported from several countries, the most extensive of which was a report for 61 elements in urine. Considerable interest was noted for carbon-based sorbents used for sample enrichment. These included carbon nanotubes, carbon cloth and a knotted PTFE reactor modified with activated carbon immobilised on the inner wall. Considerable ingenuity was demonstrated in how these were used in practice, and impressive results were obtained with clinical and food specimens. The analytical repertoire associated with in vivo XRF spectrometry was extended to include Gd in bone. Further examples of speciation methodologies were reported. It has generally been found that selenoprotein P is the major Se species in blood but a recent report claims selenosugar-1 to be the most abundant species in serum and urine. It appears that ginger could be a good food source of biologically active Se species. Among a number of interesting reports it was found that serum concentrations of Nb and Ti are increased in children with spinal implants. Methods were developed to measure Co concentrations in urine from race horses and endurance athletes following suggestions that Co supplements may be used to increase blood haemoglobin concentrations. A report of fatal poisoning from Tl2SO4 added to table salt included the concentrations measured in tissues and body fluids. An unusual example of Pb poisoning was discovered in cattle, the source, an old leaded paint feed hopper was identified from Pb isotope measurements. Copper isotope analysis was proposed by two groups to have potential for diagnosis of liver cirrhosis and for breast and colorectal cancer. © The Royal Society of Chemistry 2016.

Barkworth M.E.,Utah State University | Watson M.,Herbarium | Barrie F.R.,Missouri Botanical Garden | Belyaeva I.V.,Science Directorate | And 40 more authors.
Taxon | Year: 2016

The Special Committee on Registration of Algal and Plant Names (including fossils) was established at the XVIII International Botanical Congress (IBC) in Melbourne in 2011, its mandate being to consider what would be involved in registering algal and plant names (including fossils), using a procedure analogous to that for fungal names agreed upon in Melbourne and included as Art. 42 in the International Code of Nomenclature for algae, fungi, and plants. Because experience with voluntary registration was key to persuading mycologists of the advantages of mandatory registration, we began by asking institutions with a history of nomenclatural indexing to develop mechanisms that would permit registration. The task proved more difficult than anticipated, but considerable progress has been made, as is described in this report. It also became evident that the Nomenclature Section needs a structure that will allow ongoing discussion of registration and associated issues. Simultaneously with this report we are submitting four proposals that would provide such a structure. © International Association for Plant Taxonomy (IAPT) 2016.

Khamchatra N.,Kasetsart University | Dixon K.W.,Science Directorate | Tantiwiwat S.,Kasetsart University | Piapukiew J.,Chulalongkorn University
South African Journal of Botany | Year: 2016

Paphiopedilum villosum (Lindl.) Stein is a native epiphytic slipper orchid in Thailand. This species is now being threatened and endangered. Propagation of this species is essential for conservation and reintroduction purposes. In this study, the propagation of P. villosum was achieved through the in vitro asymbiotic and symbiotic seed germination. Seeds of P. villosum sown on asymbiotic media, Murashige and Skoog (MS), Vacin and Went (VW) and Thomale GD (TH), did not germinate within 16. weeks. Seven different fungal strains were isolated from roots of this orchid species. The germination rate index (GRI) and the development rate index (DRI) of P. villosum seeds in treatments inoculated with fungal isolates PVCP01, PVCP05, and PVCP06 was significantly higher than uninoculated control treatments. Fungal isolate PVCP01 significantly increased the GRI and DRI of every stage of protocorm development, whereas fungal isolates PVCP05 and PVCP06 were only able to promote seed germination and protocorm development to stage 2. As for the wild orchid species, P. villosum, a compatible fungus is therefore required for promoting seed germination and protocorm development. Based on analysis of morphological characters and sequences of the nuclear ribosomal transcribed spacer (ITS), fungal isolates PVCP01, PVCP 05, and PVCP06 were identified as Tulasnella sp., Ceratobasidium sp., and Flavodon sp., respectively. The information obtained from this study will be used to propagate other threatened Thai orchids for conservation and reintroduction programs. © 2016 South African Association of Botanists. Published by Elsevier B.V.

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