Feeding elicitors and precursors enhance colchicine accumulation in morphogenic cultures of <Emphasis Type="Italic">Gloriosa superba</Emphasis> L.

Morphogenic cultures of Gloriosa superba were initiated on Murashige and Skoog’s medium fortified with 2 mg L^?1 2,4-dichlorophenoxyacetic acid (2,4-D), 0.5 mg L^?1 naphthaleneacetic acid (NAA), 4% sucrose and 0.1% activated charcoal. To enhance the content of the alkaloid colchicine, morphogenic cultures were treated with different concentrations of abiotic elicitors like signalling compounds, metals, biotic elicitors, precursors and a combination of elicitors. Signalling molecules like acetyl salicylic acid (ASA) and sodium nitroprusside improved the production of colchicine. Abiotic elicitors have markedly (p?≤?0.05 or ≤?0.01) enhanced the colchicine content either at lower or higher concentrations. Among the metals, the highest amount of 11.67 mg of colchicine g^?1 dry wt was noticed at 60 mM rubidium chloride, followed by 60 mM NaCl (11.18 mg g^?1). Contrarily, in the presence of biotic elicitors such as Fusarium oxysporum, Alternaria solani, and Saccharomyces cerevisiae, colchicine content ranged only between 2 and 5.32 mg g^?1, but Bacillus subtilis repressed it. Among the aromatic amino acids, phenylalanine at 500 mg L^?1 influenced the highest accumulation of 19.48 mg g^?1 dry tissue, followed by tryptophan (12.47 mg g^?1), and tyrosine (9.87 mg g^?1), a direct precursor of colchicine biosynthesis, while intact tubers and leaves contained 4.65 and 4.16 mg of colchicine g^?1 dry tissue respectively. A combination of 10 µM AlCl₃ and 50 µM salicylic acid (SA) registered 17.34 mg g^?1 followed by 16.24 mg g^?1 tissue in presence of 1 µM HgCl₂ and 50 µM SA. The results suggest that the elicitor-stimulated colchicine accumulation was a stress response and can be exploited further for commercial production.     

A Study on Cadmium Phytoremediation Potential of Indian Mustard,Brassica juncea

The objective of this study was to investigate Cd phytoremediation ability of Indian mustard, Brassica juncea. The study was conducted with 25, 50, 100, 200 and 400 mg Kg^?1 CdCl₂ in laboratory for 21 days and Cd concentrations in the root, shoot and leaf tissues were estimated by atomic absorption spectroscopy. The plant showed high Cd tolerance of up to 400 mg Kg^?1 but there was a general trend of decline in the root and shoot length, tissue biomass, leaf chlorophyll and carotenoid contents. The tolerance index (TI) of plants were calculated taking both root and shoot lengths as variables. The maximum tolerance (TI _shoot = 87.4 % and TI _root = 89.6 %) to Cd toxicity was observed at 25 mg Kg^?1, which progressively decreased with increase in dose. The highest shoot (10791 μg g^?1 dry wt) and root (9602 μg g^?1 dry wt) Cd accumulation was achieved at 200 mg kg^?1 Cd treatment and the maximum leaf Cd accumulation was 10071.6 μg g^?1 dry wt achieved at 100 mg Kg^?1 Cd, after 21 days of treatment. The enrichment coefficient and root to shoot translocation factor were calculated, which, pointed towards the suitability of Indian mustard for removing Cd from soil.     

Enhanced colchicine production in root cultures of Gloriosa superba by direct and indirect precursors of the biosynthetic pathway

Excised root cultures of Gloriosa superba reached 7.5 g dry wt l^–1 and accumulated 240±40 g colchicine g^–1 cell dry wt after 4 weeks growth. While all precursors (except trans-cinnamic acid) enhanced colchicine content of root cultures without adversely affecting root growth, treatment with p-coumaric acid + tyramine (each at 20 mg l^–1) increased colchicine content to 1.9 mg g^–1 cell dry wt.     

Some aspects of decomposition of leaf litter of the seagrass Halophila stipulacea from the gulf of Aqaba (Jordan)

Decomposition of the seagrass Halophila stipulacea (Forsk.) Aschers. followed in situ over 340 days showed that the plant lost 40.8% of its initial weight during the first 85 days and only 21.2% over the remaining 255 days of the incubation period. The observed overall rate of decay of 0.18% day^?1 indicates the high resistance of Halophila tissue to decomposition.An exponential model showing a regularly decreasing decay coefficient was fitted to the data of weight loss. The correlation between observed and calculated weight remaining was highly significant (r = 0.9881, P < 0.0001).The samples of decomposing leaf litter harboured 2.2 × 10¹¹ bacteria g^?1 dry wt. on average and consumed 0.25?1.07 mg O₂^?1 dry wt. h^?1. The early colonizing bacteria of the detritus were mostly non-sporogenous forms. The most prominent genera involved in decomposition were Actinomyces, Arthrobacter, Bacillus and Pseudomonas, all of which are capable of degrading structural carbohydrates.     

Macrophyte-epiphyte biomass and productivity in an eelgrass (Zostera marina L.) community

The biomass, productivity (¹⁴C), and photosynthetic response to light and temperature of eelgrass, Zostera marina L. and its epiphytes was measured in a shallow estuarine system near Beaufort, North Carolina, during 1974. The maximum of the biomass (above-ground) was measured in March; this was followed by a general decline throughout the rest of the year. The average biomass was 105.0 g dry wt m^?2; 80.3 g dry wt m^?2 was eelgrass and 24.7 g dry wt m^?2 was epiphytes. The productivity of eelgrass averaged 0.88 mg C g^?1 h^?1 which was similar to that of the epiphytes, 0.65 mg C g^?1 h^?1. Eelgrass and epiphyte productivity was low during the spring and early summer, gave a maximum during late summer and fall, and declined during the winter; this progression was probably due to environmental factors associated with tidal heights. On an areal basis, the average annual productivity was 0.9 g C m^?2 day^?1 for eelgrass and 0.2 g C m^?2 day^?1 for the epiphytes. Rates of photosynthesis of both eelgrass and epiphytes increased with increasing temperature to an asymptotic value at which the system was light saturated. Both eelgrass and epiphytes had a temperature optimum of < 29 °C. A negative response to higher temperatures was also reflected in biomass measurements which showed the destruction of eelgrass with increasing summer temperatures. The data suggest that the primary productivity cycles of macrophytes and epiphytes are closely interrelated.     

Embryogenesis,plant regeneration and cardiac glycoside determination in Digitalis ferruginea subsp. ferruginea L

The present study reports, for the first time, an efficient in vitro plant regeneration protocol for Digitalis ferruginea subsp. ferruginea L. (rusty foxglove). We have used different concentrations of gibberellic acid (GA₃) on Murashige and Skoog (MS) medium to assess the germination frequency of seeds. High frequency of germination was achieved on MS medium with 1.0 mg l^?1 GA₃. 6-Benzylaminopurine (BAP) combined with α-naphtaleneacetic acid (NAA) or 2, 4-dichlorophenoxy acetic acid (2, 4-D) in the induction MS medium induced both somatic embryogensis and shoot organogenesis. The highest percentage of callus growth (85 %) was obtained when hypocotyl explants were cultured on MS medium containing 0.5 mg l^?1 2, 4-D plus 1.0 mg l^?1 BAP. The maximum mean number of somatic embryos (7.3 ± 1.3 embryos) or shoots (12.0 ± 1.1 shoots) per callus was obtained when medium contained 0.25 mg l^?1 NAA plus 1.0 mg l^?1 BAP or 0.5 mg l^?1 NAA plus 2.0 mg l^?1 BAP. The regenerated shoots easily rooted on MS medium. Higher amounts of lanatoside C [13.2 ± 0.5 mg 100 g^?1 dry weight (dw)] and digoxin (2.93 ± 0.31 mg 100 g^?1 dw) accumulation were obtained when shoots were obtained by indirect regeneration. We also investigated derivatives of cardenolides, i.e., digitoxigenin (730 ± 180 mg 100 g^?1 dw), gitoxigenin (50 ± 20 mg 100 g^?1 dw) and digoxigenin (490 ± 170 mg 100 g^?1 dw) from natural samples.     

Promotion of shoot regeneration of <Emphasis Type="Italic">Swertia chirata</Emphasis> by biosynthesized silver nanoparticles and their involvement in ethylene interceptions and activation of antioxidant activity

A complete protocol for the in vitro induction of Eclipta alba tetraploids has been optimized to enhance the wedelolactone content, an anti-cancerous compound. The effects of different concentrations of colchicine (0, 0.01, 0.05, 0.1, 0.2 and 0.3%; w/v) along with treatment durations (12, 24, 36 and 48 h) were investigated on shoot tip (ST) and nodal segment (NS). The treated explants were then incubated on Murashige and Skoog (MS) medium having 1.5 mg L^?1 N⁶-benzylaminopurine and 0.5 mg L^?1 α-napthalene acetic acid for shoot regeneration and afterward root was induced on 1.0 mg L^?1 indole-3-acetic acid enriched ½MS medium. The tetraploids of E. alba were proficiently induced by the treatment of 0.1% colchicine for 24 h. The highest tetraploid induction efficiency was obtained from ST (30.56%) in comparison to the NS (22.22%). Analysis by spectrophotometry and flow cytometry showed that colchicine treated plants contained higher quantity of DNA than diploid plants. Cytological studies demonstrated doubled the chromosome number in tetraploids (2n?=?4x?=?44) than diploids (2n?=?2x?=?22). The ploidy level enhancement lead to alteration of other traits, like increased plant height, stem diameter, leaf size, stomatal size and chlorophyll content. As determined through high performance thin-layer chromatography, the ultimate achievement of this technique is the higher accumulation of wedelolactone in tetraploid plants (300.32 µg g^?1 dry weight) in evaluation to in vitro diploid (131.31 µg g^?1 dry weight) and in vivo diploid mother plants (93.26 µg g^?1 dry weight), thus improving the pharmaceutical value of E. alba.     

Vertical Profile of Phosphatase Activity in the Sundarban Mangrove Forest,North East Coast of Bay of Bengal,India

Impact of phosphate solubilizing bacteria along with soil phosphatase activity on phosphorous cycle was found to be quiet interesting in the Sundarban mangrove ecosystem. Soil phosphatase activity showed a decreasing pattern with increase in depth [soil phosphatase activity (μg pnp produced g^?1 dry wt of soil) = 906.85 – 5.6316 Depth (cm)] from the deep forest region of the Sundarban forest ecosystem. Soil salinity showed a very little effect on soil phosphatase activity whereas soil temperature and pH was found to show significant impact on the soil phosphatase activity. This ensured that the microbes associated with phosphate mineralization present in the Sundarban forest ecosystem are more tolerant to fluctuation in salinity than that of temperature and pH. A direct correlation was perceptible between the number of phosphate solubilizing bacteria and phosphatase activity in the soil during the study period from 2007 to 2012. Soil phosphate concentration was found to be directly governed by the soil phosphatase activity [The regression equation is: avg PO₄^?3-P (μg g^?1 dry wt of soil) = 0.0311 + 0.000606 soil phosphatase activity (μg pnp produced g^?1 dry wt of soil); R² = 63.2%, p < 0.001, n = 62].     

Manipulation of culture strategies to enhance capsaicin biosynthesis in suspension and immobilized cell cultures of Capsicum chinense Jacq. cv. Naga King Chili

Manipulation of culture strategies was adopted to study the influence of nutrient stress, pH stress and precursor feeding on the biosynthesis of capsaicin in suspension and immobilized cell cultures of C. chinense. Cells cultured in the absence of one of the four nutrients (ammonium and potassium nitrate for nitrate and potassium stress, potassium dihydrogen orthophosphate for phosphorus stress, and sucrose for sugar stress) influenced the accumulation of capsaicin. Among the stress factors studied, nitrate stress showed maximal capsaicin production on day 20 (505.9 ± 2.8 μg g^?1 f.wt) in immobilized cell, whereas in suspension cultures the maximum accumulation (345.5 ± 2.9 μg g^?1 f.wt) was obtained on day 10. Different pH affected capsaicin accumulation; enhanced accumulation of capsaicin (261.6 ± 3.4 μg g^?1 f.wt) was observed in suspension cultures at pH 6 on day 15, whereas in case of immobilized cultures the highest capsaicin content (433.3 ± 3.3 μg g^?1 f.wt) was obtained at pH 5 on day 10. Addition of capsaicin precursors and intermediates significantly enhanced the biosynthesis of capsaicin, incorporation of vanillin at 100 μM in both suspension and immobilized cell cultures resulted in maximum capsaicin content with 499.1 ± 5.5 μg g^?1 f.wt on day 20 and 1,315.3 ± 10 μg g^?1 f.wt on day 10, respectively. Among the different culture strategies adopted to enhance capsaicin biosynthesis in cell cultures of C. chinense, cells fed with vanillin resulted in the maximum capsaicin accumulation. The rate of capsaicin production was significantly higher in immobilized cells as compared to freely suspended cells.     

Induction of astaxanthin formation by reactive oxygen species in mixotrophic culture of Chlorococcum sp.

The induction of astaxanthin formation by reactive oxygen species in mixotrophic culture of Chlorococcum sp. was investigated. H₂O₂ (0.1 mM) enhanced the total astaxanthin formation from 5.8 to 6.5 mg g^–1 cell dry wt. Fe²⁺ (0.5 mM) added to the medium with H₂O₂ (0.1 mM) further promoted astaxanthin formation to 7.1 mg g^–1 cell dry wt. Similarly, Fe²⁺ (0.5 mM) together with methyl viologen (0.01 mM) promoted astaxanthin formation to 6.3 mg g^–1 cell dry wt. In contrast, an addition of KI (1 mM), a specific scavenger for hydroxyl radicals (OH), together with H₂O₂ (0.1 mM) and Fe²⁺ (0.5 mM), to the medium decreased astaxanthin formation to 1.8 mg g^–1 cell dry wt. KI (1 mM) also inhibited the enhancement of carotenogenesis by superoxide anion radicals (O₂ ^–), with a decrease of astaxanthin formation to 1.7 mg g^–1 cell dry wt. This suggested that O₂ ^– might be transformed to OH before promoting carotenogenesis in Chlorococcum sp.     

Case study on the efficacy of a lanthanum-enriched clay (Phoslock®) in controlling eutrophication in Lake Het Groene Eiland (The Netherlands)

Lake Het Groene Eiland was created in the beginning of 2008 by construction of dikes for isolating it from the surrounding 220-ha water body. This so-called claustrum of 5 ha was treated using lanthanum-modified clay (Phoslock^®) to control eutrophication and mitigate cyanobacterial nuisance. Cyanobacteria chlorophyll-a were significantly lower in the claustrum than those in the reference water body, where a massive bloom developed in summer, 2008. However, PO₄-P and TP did not statistically differ in these two waters. TN and NO₃-N were significantly lower in the claustrum, where dense submerged macrophytes beds developed. Lanthanum concentrations were elevated after the applications of the modified clay in the claustrum, but filterable lanthanum dropped rapidly below the Dutch standard of 10.1 μg l^?1. During winter, dozens of Canada geese resided at the claustrum. Geese droppings contained an average of 2 mg PO₄-P g^?1 dry weight and 12 mg NH₃-N g^?1 dry weight and might present a growing source of nutrients to the water. Constructing the claustrum enabled unrestricted bathing in subsequent three summers, as no swimming bans had to be issued due to cyanobacteria blooms. However, the role of the modified clay in this positive outcome remains unclear, and longevity of the measures questionable.     

Decay rates and nitrogen dynamics of decomposing watercress (Nasturtium officinale R.Br.)

We examined the decomposition of watercress in the laboratory at 10° and 20 °C, and in the field. Rates varied from 0.058 g g^?1 day^?1 in the laboratory to 0.115 g g^?1 day^?1 in the field. There was a rapid generation of particles of size <500 µm. It is thought that washout of these from the litterbags in the field accounted for high field decomposition rate. Formation of dissolved nitrogen compounds during decomposition followed a time series from NH _inf4 ^sup+ to NO _in2 ^sup? to NO _inf3 ^sup? withdissolved organic nitrogen accumulating at the end of decomposition. Ammonification rates were 480 and 657 g NH₄-N g^?1 (dry wt) day^?1 and nitrification rates on the decomposing tissue were 640 and 571 µg NO₃-N g^?1 (dry wt) day^?1 at 10° and 20 °C respectively. Fifty-six per cent of the initial plant N was regenerated as NO₃-N 21% as DON and 25% remained as refractory particulate N.     

Influence of light and temperature on photosynthesis and respiration by Pithophora oedogonia (Mont.) Wittr. (chlorophyceae)

Rates of net photosynthesis and respiration were determined for Pithophora oedogonia (Mont.) Wittr. acclimatized to 56 combinations of light (7–1200 μE m^?2 s^?1) and temperature (5–35°C). Conditions for maximum net photosynthesis were estimated to be 26°C and 970 μE m^?2 s^?1. The rate of net photosyntheses varied considerably with temperature, with the maximum measured value (9.67 mg O₂ h^?1 g dry wt.^?1) occurring at 25°C. Respiration rate increased with temperature and the light received just prior to measurement. The maximum respiration rate (7.05 mg O₂ g^?1 h^?1) occurred at 30°C and 1200 μE m^?2 s^?1. Exposure of Pithophora to light levels of 600 or 1200 μE m^?2 s^?1 prior to determination of the respiration rate resulted in significantly elevated levels of oxygen consumption at temperatures ≥ 15°C. The relationship between light, temperature and photosynthesis and respiration were summarized as three-dimensional response surfaces.     

Characterization of natural variation for zinc, iron and manganese accumulation and zinc exposure response in Brassica rapa L.

Brassica rapa L. is an important vegetable crop in eastern Asia. The objective of this study was to investigate the genetic variation in leaf Zn, Fe and Mn accumulation, Zn toxicity tolerance and Zn efficiency in B. rapa. In total 188 accessions were screened for their Zn-related characteristics in hydroponic culture. In experiment 1, mineral assays on 111 accessions grown under sufficient Zn supply (2 μM ZnSO₄) revealed a variation range of 23.2–155.9 μg g⁻¹ dry weight (d. wt.) for Zn, 60.3–350.1 μg g⁻¹ d. wt. for Fe and 20.9–53.3 μg g⁻¹ d. wt. for the Mn concentration in shoot. The investigation of tolerance to excessive Zn (800 μM ZnSO₄) on 158 accessions, by using visual toxicity symptom parameters (TSPs), identified different levels of tolerance in B. rapa. In experiment 2, a selected sub-set of accessions from experiment 1 was characterized in more detail for their mineral accumulation and tolerance to excessive Zn supply (100 μM and 300 μM ZnSO₄). In this experiment Zn tolerance (ZT) determined by relative root or shoot dry biomass varied about 2-fold. The same six accessions were also examined for Zn efficiency, determined as relative growth under 0 μM ZnSO₄ compared to 2 μM ZnSO₄. Zn efficiency varied 1.8-fold based on shoot dry biomass and 2.6-fold variation based on root dry biomass. Zn accumulation was strongly correlated with Mn and Fe accumulation both under sufficient and deficient Zn supply. In conclusion, there is substantial variation for Zn accumulation, Zn toxicity tolerance and Zn efficiency in Brassica rapa L., which would allow selective breeding for these traits.     

Pea growth and ion accumulation at varying seed density

Decreased accumulation of elements, particularly of nitrogen, had in dense stand a negative influence on the plants, in spite of the supply of fresh solution and the control of the concentration of nutrients in the pots. The fresh weight and the dry matter of one plant were reduced substantially with rising stand density (from 5 to 10, 20, 40 and 80 plants per 450 sq. cm); the RGR value, the relative absorption rate I_M, the content of all tested elements calculated per one plant, the chlorophyll content in the overground parts of one plant, and the distribution index decrease. Qualitatively the same influence is caused by deficiency of nutrients. Plant dying and self-thinning of the culture occurred in denser stand in the course of cultivation. The root-weight ratio rose with stand densification, particularly at the end of the experiment. The net assimilation rate (NAR) related to chlorophyll dropped with stand density; NAR at density “80” rose slightly from the 22nd day of cultivation and did so at further lower densities. Almost all NAR values lie over the control value at the last measurement. The chlorophyll content in mg g^?1 dry matter of the overground parts rose with stand density to density “40” (41% more than at density “5”); afterwards it dropped. The accumulation (in mg g^?1 d.m.) of phosphorus ions was higher in the plants from dense cultures compared with density “5”, particularly in the roots. The accumulation of potassium was near to the control value (“5”), while that of nitrogen was lower. The utilization quotients of phosphorus and potassium in denser stands were the same or negligibly lower than at density “5”. They were a little higher in nitrogen than in the controls. Also the ratio RGR/I_M was a little higher than in denser stands. The root-weight ratio, the accumulation of elements in mg g^?1 d.m., the chlorophyll content in mg g^?1 d.m., NAR_ch, the utilization quotient, and the ratio RGR/I_M differed qualitatively by the densification of the culture (with complete mineral nutrition) from the influence of element deficiency (at the same stand density).     

Improvement of phenylethanoid glycosides production by a fungal elicitor in cell suspension culture of Cistanche deserticola

When, on the 15th day of growth, an elicitor from Fusarium solani was added at 40 mg l^–1 to Cistanche deserticola cell suspension cultures, the contents of echinacoside, acteoside and total phenylethanoid glycosides (PeGs) in cultured cells all increased over the next 27 d by over 100% to 15 mg g^–1 dry wt, 9 mg g^–1 dry wt and 57 mg g^–1 dry wt, respectively. The final biomass (1.3 mg dry wt ml^–1) was not affected.     

Flux of lead in submerged plants and its relevance to a freshwater system

The fluxes of lead in submerged freshwater angiosperms, mosses and benthic algae were investigated by laboratory and field observations. Laboratory experiments showed that the initial uptake of lead by angiosperm shoots and Navicula sp. was rapid (up to 0.07 mg Pb g^?1 dry weight min ^?1 from a solution containing 1.0 mg Pb l^?1), and over-whelmingly passive. Mosses were especially efficient at sorbing lead from solutions containing less than 1.0 mg Pb l^?1 . Rates of uptake increased with rising external concentrations, but decreased with time. Anatomical and morphological characteristics of plant tissues affected metal flux and an epiphytic covering of Navicula (i.e., an Aufwuchs community) sorbed metal and reduced uptake into tissues by a third. Up to 90% of the lead sorbed in the first hour by shoots of Elodea canadensis Michx from a solution containing 1.0 mg Pb l^?1 was released within 14 days of transfer into a lead-free medium; 10% was irreversibly bound.Moss monitors placed in Ullswater, a lake with sediments containing up to 26 mg Pb g^?1 dry weight, confirmed that the metal is brought into circulation during turbulence, but not in periods of calm. Shoots of Elodea collected from the lake contained up to 0.3 mg g^?1 dry weight non-exchangeable lead. Young shoots tended to contain less than older shoots (0.12 compared with 0.3 mg Pb g^?1), and leaf more than stem tissues. The fluxes of lead from the environment through Aufwuchs and submerged plants are discussed.     

Effect of salinity on phosphate accumulation and injury in soybean

Certain soybean [Glycine max (L.) Merr.] cultivars that are grown in saline nutrient cultures are killed when the inorganic phosphate (Pi) concentration in the substrate exceeds 0.10 mM. To determine the role of Na and Cl on this adverse salinity×Pi interaction, four cultivars, Clark, Clark 63, Lee, and Lee 74 were grown in the greenhouse in nutrient solutions salinized with 1) Cl and NO₃ salts to produce treatments with variable amounts of Cl or 2) with NaCl or KCl and CaCl₂ to obtain treatments with and without Na. At an osmotic potential of ?0.34 MPa, all salts enhanced Pi uptake and accumulation in the tissue of plants grown in ≧0.12 mM substrate Pi. Leaf Cl concentration was linearly related (r²≥0.9) to the mole fraction (mf) of Cl in the substrate, therefore excess substrate NO₃ did not greatly influence leaf Cl accumulation. Foliar injury was only observed on plants grown in saline solutions at high Pi (≥0.12 mM) and was not alleviated when KCl replaced NaCl in the substrate. This indicates that Na did not play a direct role in the salinity×Pi interaction. However, as the mf of Cl increased, severity of injury increased. The severity of injury, and its symptoms, were dependent upon leaf P and Cl concentration. Plants died when Cl and P in their leaves exceeded 800 and 600 mmol kg^?1 dry wt, respectively (e.g., Clark 63 grown at mf of Cl=1). The necrotic leaves were beige in color. Leaves that contained P in excess of 600 mmol kg^?1 dry wt and Cl between 150–200 mmol kg^?1 dry wt, were severely injured and reddish-brown in color (e.g., Clark 63 at mf of Cl=1/4 and Lee 74 Pi grown at mf of Cl=1). When leaf Cl was below 150 mmol kg^?1 dry wt, development of reddish-brown coloration in the leaves was sporadic. The adverse salinity×Pi interaction observed on these soybean variaties, therefore, was caused by a synergistic interaction between P and Cl in the leaves.     

In vitro production of sedative galphimine B by cell suspension cultures of Galphimia glauca

The sedative triterpene, galphimine B (1), was detected in cell suspension-batch cultures of Galphimia glauca. The effect of inoculum size, growth regulators and different concentrations of sucrose, nitrates and phosphates was evaluated. A two-stage batch process for biomass production and accumulation of compound 1 was established. Major cellular growth (15 g l^–1 dry wt) was obtained in the first stage with naphthaleneacetic acid (2 mg l^–1) + kinetin (2 mg l^–1). Adding 4 mg 2,4-dichlorophenoxyacetic l^–1 acid in the second stage resulted in the highest accumulation of 1 (0.21 mg g^–1 dry wt) which was 36% higher with respect to calluses and comparable to that obtained from wild plants.     

Vitamin analysis of five planktonic microalgae and one macroalga

Vitamin analysis was carried out on five microalgae used in aquaculture:Tetraselmis suecica, Isochrysis galbana, Pavlova lutheri, Skeletonema costatum andChaetoceros calcitrans and one macroalga,Sargassum muticum, which is invasive on the Atlantic shores of France. Both liposoluble (provitamin A, E, K) and hydrosoluble (B₁, B₂, B₆, B₁₂, C, PP) vitamins were quantified. For most of them, greater amounts were obtained in the algal products than in the usual sources. On a dry weight basis,Tetraselmis suecica contained 4280 μg g^?1 provitamin A and 6323 μg g^?1 vitamin E,Pavlova lutheri 1162 μg g^?1 vitamin B₁₂ and 837 μg g^?1 vitamin C,Isochrysis galbana 2690 μg g^?1 vitamin PP and 183 μg g^?1 vitamin B₆, andSkeletonema costatum 710 μg g^?1 vitamin B₁.