Betaine distribution in the Malvaceae

Aerial parts of 26 taxa, distributed in 18 genera and all 5 tribes of the Malvaceae have been examined for the presence of betaines. Glycinebetaine was obtained in high yield (0.5-4.6%, dry weight) from all the plants studied, except Abelmoschus moschatus, in extracts of which glycinebetaine was not detected. Trigonelline was recorded for 16 of the plants tested, but the yields were low (0.005-0.07%, dry weight). Roots and flowers of a few of the species were also examined for betaines. The same compounds as those found in the aerial parts were usually detected, but the glycinebetaine contents of the roots and flowers were considerably lower.     

Betaine distribution in Angiosperms

Over 140 Angiosperm species, included in 45 of the 62 orders listed by Engler, have been investigated for the presence of betaines, which were detected in 86% of the species examined and in 43 of the orders. Moreover, betaines were reported earlier in a further seven of the orders. Thus, it can be concluded that betaines are very widely distributed in Angiosperms. The most commonly detected betaines in the study were glycinebetaine and trigonelline, although others, such as prolinebetaine, trans-4-hydroxyprolinebetaine and pipecolatebetaine were found, although with a very restricted distribution. In the large majority of species tested, betaine levels were low (below 0.1%, dry weight).     

Chilean Bromeliaceae: diversity, distribution and evaluation of conservation status

Chile is home to 23 species of Bromeliaceae, including 2 subspecies and 4 varieties. Twenty species are endemic to the country. We examined 883 herbarium specimens from 27 herbaria for our treatment of the Bromeliaceae for the “Flora de Chile”. These data and field observations resulted in a comprehensive database that we used to generate distribution maps for each species. We applied ecological niche modelling to reveal distribution areas and centers of Bromeliaceae diversity. We further analysed the collecting dates of the herbarium specimens to assess possible changes in species abundance. In this study we assess the conservation status of the bromeliad species in Chile. IUCN categories were assigned to the 27 bromeliad taxa as follows: Critically endangered: 4, Endangered: 6, Vulnerable: 11, Near threatened: 2, Least concern: 4. No species has become “Extinct” up to now. We also put forth a hypothesis about their biogeographic history.     

Physiological ecology of the Bromeliaceae

The physiological ecology of members of the Bromeliaceae is reviewed with an emphasis on photosynthesis and water relations. Terrestrial and epiphytic species are, for the most part, treated separately. Water relations, photosynthetic pathways, and photosynthetic responses to light, temperature, drought, atmospheric moisture, elemental nutrients, and pollutants are considered from an ecological perspective. In addition, appendices provide values of numerous ecophysiological parameters for all species studied thus far. Results of this review include the following: (1) the ecophysiology of terrestrial and epiphytic species is surprisingly similar; (2) approximately two-thirds of bromeliads are CAM plants and occupy arid sites or are epiphytic; (3) many species are adapted to full or partial shade, yet can grow in full sunlight; (4) photosynthesis is optimal when day temperatures are warm and night temperatures are cool; (5) species with heavy trichome indumenta on their leaf surfaces are capable of absorbing atmospheric water vapor, yet improvement of tissue water relations is unlikely; (6) heavy trichome covers also suppress CO₂ exchange when leaf surfaces are wetted; (7) high levels of recycling of respiratory CO₂ via CAM occur in many species, especially under stress; and (8) tissue osmotic and water potentials of nearly all bromeliads investigated are seldom more negative than -1.0 MPa. A potential explanation of the mechanisms underlying maintenance of high tissue water potentials despite large water losses during droughts is discussed. In summary, the diversity of physiological adaptations to the environment in the few bromeliads studied thus far is impressive, but likely will be surpassed with investigation of more species in the Bromeliaceae.     

Ecoregional distribution of potentially useful species of Araceae and Bromeliaceae as non-timber forest products in Bolivia

In Bolivia, the plant families Araceae and Bromeliaceae offer numerous non-timber products, including ornamental plants, medicines, foods, and fibers. The economic potential for the utilization of these resources depends critically on the distribution of potentially useful species in different ecoregions in Bolivia. We conducted both a bibliographical revision of uses and ecological field work at 43 sites in the Bolivian Andes and lowlands to assess the potential for sustainable use as suggested by the Rapid Vulnerability Assessment method. The ecological criteria used for the evaluation were abundance (frequency), life form, geographical distribution, and habitat preference. We found that Bolivia has a striking number of potentially useful species of both families but that their potential use differs among ecoregions. Araceae were most species-rich and frequent in the humid lowland and montane forests. In these ecoregions, this family has a particular local importance mainly as traditional medicines and a great potential as ornamental plants. In contrast, economically useful bromeliads are best represented in seasonally dry forest habitats, especially for the production of fibres. Many species of bromeliads, which also occur in humid montane forests, although rare, are potentially important for commercialisation as ornamental species. This study shows that the uses of Araceae and Bromeliaceae are manifold and could be greatly increased through efficient management, although with different strategies according to the different ecoregions.     

Betaine lipids in chlorarachniophytes

Evolving from the endosymbiosis of a green algal cell by a filose amoeba or amoeboflagellate, the chimearic chlorarachniophytes combine unique features retained from both of their ancestral units. They have preserved from the endosymbiont only the nucleomorph and chloroplast. Four strains from three genera of this algal class were studied to identify a set of non‐phosphorous‐containing polar lipids and their associated fatty acids using the techniques of positive‐ion electrospray ionization/mass spectrometry (ESI/MS) and electrospray ionization/mass spectrometry/mass spectrometry (ESI/MS/MS). Fourteen non‐phosphorous‐containing polar lipids, classified as betaine lipids were primarily identified as forms of diacylglyceryl‐N,N,N‐trimethylhomoserine (DGTS) and its structural isomer diaclyglycerylhydroxymethyl‐N,N,N‐trimethyl‐β‐alanine (DGTA). Though the number of forms of DGTA and DGTA were roughly equal, DGTS composed more of the polar lipid portion present in three of the strains tested, while the fourth, Lotharella globosa, was dominated by forms of DGTA. In addition, a lipid tentatively identified as diacylglycerylcarboxyhydroxymethylcholine (DGCC) was observed twice in minor amounts. The polar lipid‐associated fatty acids of the aforementioned algal strains generally included dodecanoic acid (12:0), tetradecanoic acid (14:0), hexadecanoic acid (16:0), octadecanoic acid (18:0), octadecenoic acid (18:1), and eicosapentaenoic acid [20:5(n‐3)]. The differences in betaine lipid content among the species studied may allow for further conclusions to be drawn regarding the taxonomy of chlorarachniophytes.     

Betaine lipids

Diacylglyceryltrimethylhomoserine (DGTS) and diacylglyceryl hydroxymethyltrimethyl-β-alanine (DGTA) belong to a new type of glycerolipids called betaine lipids, which are composed of diacylglycerol andN-permethylated hydroxyamino acids, that are linked by an ether linkage. Betaine lipids are widely distributed in lower plants and algae as well as in some non-photosynthetic microorganisms. They are no longer regarded as “unusual” lipids but are important constituents of membranes of lower organisms. The present state of knowledge of the phylogenetic distribution, the fatty acid composition, the thermal properties, and the biosynthesis of the bataine lipids is briefly summarized in this review in a perspective of a future search for the biological roles and activities of betaine lipids. Recipient of the Botanical Society Award of Young Scientists, 1991.     

Economic and hydraulic divergences underpin ecological differentiation in the Bromeliaceae

Leaf economic and hydraulic theories have rarely been applied to the ecological differentiation of speciose herbaceous plant radiations. The role of character trait divergences and network reorganization in the differentiation of the functional types in the megadiverse Neotropical Bromeliaceae was explored by quantifying a range of leaf economic and hydraulic traits in 50 diverse species. Functional types, which are defined by combinations of C₃ or Crassulacean acid metabolism (CAM) photosynthesis, terrestrial or epiphytic habits, and non‐specialized, tank‐forming or atmospheric morphologies, segregated clearly in trait space. Most classical leaf economic relationships were supported, but they were weakened by the presence of succulence. Functional types differed in trait‐network architecture, suggesting that rewiring of trait‐networks caused by innovations in habit and photosynthetic pathway is an important aspect of ecological differentiation. The hydraulic data supported the coupling of leaf hydraulics and gas exchange, but not the hydraulic safety versus efficiency hypothesis, and hinted at an important role for the extra‐xylary compartment in the control of bromeliad leaf hydraulics. Overall, our findings highlight the fundamental importance of structure–function relationships in the generation and maintenance of ecological diversity.     

Species composition of Bromeliaceae and their distribution at the Massambaba restinga in Arraial do Cabo, Rio de Janeiro, Brazil

We studied some ecological parameters such as richness, abundance, density, biomass and variation in species composition in four vegetation zones and in a zone with anthropic disturbance in the Massambaba Restinga in Arraial do Cabo, Rio de Janeiro State. We sampled 100 plots of 100 m(2) (10 x 10 m) recording the bromeliad species and their abundance. We found a total of seven bromeliad species, with Vriesea neoglutinosa (5647 ramets) and Tillandsia stricta (1277 ramets) being the most abundant. The vegetation zone called Clusia shrubs had the highest richness (S = 5) and density (6360 ramets.ha(-1)) of bromeliads. The differences found in abundance and variation in species composition among vegetation zones seems to be related to the vegetation structure of each zone.     

四种观赏凤梨的离体繁殖

以粉菠萝[Aechmea fasciata (Lindl.)Baker]、八宝剑（Vriesea poelmanii Hort.)、虎斑姬凤梨[Cryptanthus zonatus(Vis.)Beer]、七彩羞凤梨[Neoregelia carolinae (Beer)L.B.Sm.]等的幼株茎段为外植体,以MS＋NAA 0.5mg L^-1 BA 5mg L^-1为诱导培养基,MS＋BA 1mg L^-1 NAA 0.1mg L^-1为增殖培养基,可获得较好增殖效果。用1／2MS＋NAA 0.5mg L^-1生根效果较好,以椰糠：砂＝1：1,或椰糠：泥炭土：蛭石＝1：1：1为基质移苗的成活率均达95％以上。     

Diversity and evolution of microsporogenesis in Bromeliaceae

In this study, we explore the features of microsporogenesis in Bromeliaceae and, in particular, the diversity and evolution of additional callose deposits. Cytokinesis type, cell wall formation, tetrad form and patterns of additional callose deposition after intersporal wall formation were studied in 12 species of Bromeliaceae (each from a different genus) presenting four different aperture patterns. Microsporogenesis is highly conserved, with successive cytokinesis, centrifugal cell plate formation and predominantly tetragonal and decussate tetrads, as in many monocots, but five different patterns of additional callose deposition were recorded. The optimization of patterns of additional callose deposition on the phylogeny of Bromeliaceae reveals convergences. Additional callose deposition is a variable and labile feature of microsporogenesis in Bromeliaceae and is linked, to some extent, to aperture pattern. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 36–45.     

Betaine accumulation in salt-stressed sorghum

Two analytical methods for measuring betaine were compared in a study of betaine accumulation in salt-stressed sorghum. Spectrophotometric determination of betaine as the p -bromophenacyl ester is highly sensitive and specific. However, a periodide assay was found to be more convenient for screening numerous plant samples without undue sacrifice in accuracy.
The accumulation of betaine in grain sorghum [ Sorghum bicolor (L.) Moench] cvs NK 265 and Double TX was measured in salt-stressed plants grown hydroponically and in the field and in drought-stressed potted plants. Neither drought nor mild salinity (-0.2 MPa) stress was effective in stimulating betaine accumulation. However, when the osmotic potential of the culture solution was lowered to -0.8 MPa, betaine levels in the shoots rose rapidly for 12 days after initiation of salination, and then declined, apparently because of dilution by plant growth. In young leaf blades, betaine was strongly accumulated up to 70–75 μmol (g dry weight)⁻¹; the concentration in leaf sheaths was less than 6 μmol (g dry weight)⁻¹.
In the field, betaine levels in salt-stressed sorghum increased 6- to 7-fold over the basal level of the control plants. In a comparable study of two wheat species ( Triticum aestivum L. cv. Probred and T. durum Desf. cv. 1000-D), betaine increased only 3- to 4-fold over unstressed plants.     

Oxidation of Betaine Aldehyde by Betaine Dehydrogenase from Spinach Leaves

Betaine content in leaves of fifteen plant species was determined. The results showed higher betaine levels in those salt-, drought-, and chilling-resistant species. Betaine aldehyde dehydrogenase (BADH, EC 1.2.1.8 ) was isolated and partially purified from spinach leaves. Some properties of this enzyme were studied. BADH was precipitated by 60% saturation of (NH4)2SO4. Its activity was not detected in 70% saturation of (NH4)2SO4. BADH has two isoenzymes. The activity of BADH was quite stable below –80℃. It was inhibited by 0.125–1.0 mol/L NaG1 or KC1 but not by Mn2+ and Mo6+, and slightly increased by Mg2+.     

Development and characterization of microsatellite markers for Vriesea simplex (Bromeliaceae) and cross-amplification in other species of Bromeliaceae

Ten polymorphic microsatellite loci were isolated and characterized for Vriesea simplex epiphytic and endemic species from the Brazilian Atlantic Rainforest. The number of alleles per locus ranged from 2 to 16. The observed and expected heterozygosity ranged from 0.000 to 0.414 and 0.068 to 0.795, respectively. All loci departed significantly from Hardy–Weinberg equilibrium. Linkage disequilibrium was not detected in any pair of loci. Transferability of 10 loci was positive across ten other Bromeliaceae species. The loci will be used for studying population genetic structure, mating system variation, and the origin and maintenance of reproductive barriers to gene exchange among sympatric Vriesea species.