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1.
José Juan Barrera-Alba Sônia Maria Flores Gianesella Gleyci Aparecida Oliveira Moser Flávia Marisa Prado Saldanha-Corrêa 《Hydrobiologia》2008,598(1):229-246
Heterotrophic bacterial and phytoplankton biomass, production, specific growth rates and growth efficiencies were studied
in July 2001 and January 2002 during both spring and neap tides, along a tidal cycle, at three sites in a subtropical estuary.
Major freshwater inputs located in the Northern region led to differences in both phytoplankton and bacterioplankton biomass
and activity along the estuary. While in the Northern region phytoplankton is light-limited, with mean phytoplankton production
(PP) between 1.1 and 1.9 μg C l−1 h−1 and mean specific growth rates (PSG) between 0.14 and 0.16 d−1, the Southern region registered values as high as 24.7 μg C l−1 h−1 for PP and 2.45 d−1 (mean PP between 3.4 and 7.3 μg C l−1 h−1; mean PSG between 0.28 and 0.57 d−1). On the other hand, maximum bacterial production (BP: 63.8 μg C l−1 h−1) and specific growth rate (BSG: 32.26 d−1) were observed in the Northern region (mean BP between 3.4 and 12.8 μg C l−1 h−1; mean BSG between 1.98 and 6.67 day−1). These bacterial activity rates are among the highest recorded rates in estuarine and coastal waters, indicating that this
system can be highly heterotrophic, due to high loads of allochthonous carbon (mainly derived from mangrove forest). Our results
also showed that, despite that BP rates usually exceeded PP, in the Southern region BP may be partially supported (∼45%) by
PP, since a significant regression was observed between BP and PP (r = 0.455, P < 0.001).
Handling editor: P. Viaroli 相似文献
2.
Tissue culture and plant regeneration of blue grama grass, Bouteloua gracilis (H.B.K.) Lag. Ex Steud
Gerardo Armando Aguado-Santacruz José Luis Cabrera-Ponce Víctor Olalde-Portugal M. A. Rosario Sánchez-González Judith Márouez-Guzmán Luis Herrera-Estrella 《In vitro cellular & developmental biology. Plant》2001,37(2):182-189
Summary As a first step towards applying biotechnology to blue grama, Bouteloua gracilis (H. B. K.) Lag. ex Steud., we have developed a regenerable tissue culture system for this grass. Shoot apices were isolated
from 3-d-old seedlings and cultured in 15 different growth regulator formulations combining 2,4-dichlorophenoxyacetic acid
(2,4-D), Picloram (4-amino-3, 5,6-trichloropicolinic acid), N6-benzyladenine (BA) or adenine (6-aminopurine). The highest induction of organogenic callus was obtained with formulations
containing 1 mg l−1 (4.52 μM) 2,4-D plus 0.5 mg l−1 (2.22 μM) BA. and 2 mg l−1 (8.88 μM) BA plus 1 mg l−1 (4.14 μM) Picloram with or without 40 mg l−1 (296.08 μM) adenine. Lower frequencies of induction were obtained for embryogenic as compared to organogenic callus. The most efficient
treatments for induction of embryogenic callus contained 2 mg l−1 (9.05 μM) 2,4-D combined with 0.25 (1.11 μM) or 0.50 mg l−1 (2.22 μM) BA, or 1 mg l−1 (4.52 μM) 2,4-D with 0.50 mg l−1 (2.22 μM) BA. Regeneration was achieved in hormonefree Murashige anmd Skoog (MS) medium, half-strength MS medium or MS medium plus
1 mg l−1 (1.44 μM) gibberellic acid. The number of plantlets regenerated per 500 mg callus fresh weight on MS medium ranged from 9 for 2 mg
l−1 (9.05 μM) 2,4-D to 62.2 for induction medium containing 2 mg l−1 (8,28 μM) Picloram, 1 mg l−1 (4.44 μM) BA and 40 mg l−1 (296.08 μM) adenine. Regnerated plants grown in soil under greenhouse conditions reached maturity and produced seeds. 相似文献
3.
Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 NAA, 0.2 mg l−1 kinetin and casein hydrolysate 250 mg l−1. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of 500 μM salicylic acid,
100 μM methyl jasmonate, 500 μM ethrel and 500 mg l−1 yeast extract, added on the 7th day, were enhanced by 3- to 6-fold (5–11 mg l−1) by the 15th day. 相似文献
4.
In January 2004 the microplankton community from the coastal waters of Terre Adélie and Georges V Land (139°E–145°E) was studied.
Results showed a diatom-dominated bloom with chlorophyll a levels averaging 0.64 μg l−1 at 5 m depth (range 0.21–1.57 μg l−1). Three geographic assemblages of diatoms were identified, based on principal diatom taxa abundances. The stratified waters
near the Mertz Glacier presented highest phytoplankton biomasses (0.28–1.57 μg Chl a l−1 at 5 m) and diatom abundances (6,507–70,274 cells l−1 at 5 m), but low diversity, dominated by Fragilariopsis spp. Lower biomasses (0.38–0.94 μg Chl a l−1 at 5 m) and abundances (394–9,058 cells l−1 at 5 m) were observed in the mixed waters around the Astrolabe Glacier with a diverse diatom community characterised by larger
species Corethron pennatum and Rhizosolenia spp. Finally an intermediate zone between them over the shallower shelf waters of the Adélie Bank represented by Chaetoceros criophilus, where biomasses (0.21–0.35 μg Chl a l−1 at 5 m) and abundances (1,190–5,431 cells l−1 at 5 m) were lowest, coinciding with the presence of abundant herbivorous zooplankton. 相似文献
5.
Toshiya Katano Shin-ichi Nakano Hiroyuki Ueno Osamu Mitamura Kaori Anbutsu Masayuki Kihira Yasuhiro Satoh Takeshi Satoh Valentin V. Drucker Yuji Tanaka Yuki Akagashi Masahito Sugiyama 《Limnology》2008,9(3):243-250
The abundance and composition of phytoplankton were investigated at six stations along a transect from the Barguzin River
inflow to the central basin of Lake Baikal in August 2002 to clarify the effect of the river inflow on the phytoplankton community
in the lake. The water temperature in the epilimnion was high near the shore at Station 1 (17.3°C), probably due to the higher
temperature of the river water, and gradually decreased offshore at Station 6 (14.5°C). Thermal stratification developed at
Stations 2–6, and a thermocline was observed at a 17–22-m depth at Stations 2–4 and an 8–12-m depth at Stations 5 and 6. The
concentrations of nitrogen and phosphorus nutrients in the epilimnion at all stations were <1.0 μmol N l−1 and <0.16 μmol P l−1, respectively. Relatively high concentrations of nutrients (0.56–7.38 μmol N l−1 and 0.03–0.28 μmol P l−1) were detected in the deeper parts of the euphotic zone. Silicate was not exhausted at all stations (>20 μmol Si l−1). The chlorophyll a (chl. a) concentration was high (>10 μg l−1) near the shore at Station 1 and low (<3 μg l−1) at five other stations. The <2 μm fraction of chl. a in Stations 2–6 ranged between 0.80 and 1.85 μg l−1, and its contribution to total chl. a was high (>60%). In this fraction, picocyanobacteria were abundant at all stations and ranged between 5 × 104 and 5 × 105 cells ml−1. In contrast, chl. a in the >2 μm fraction varied significantly (0.14–11.17 μg l−1), and the highest value was observed at Station 1. In this fraction, the dominant phytoplankton was Aulacoseira and centric diatoms at Station 1 and Cryptomonas, Ankistrodesmus, Asterionella, and Nitzschia at Stations 2–6. The present study demonstrated the dominance of picophytoplankton in the pelagic zone, while higher abundance
of phytoplankton dominated by diatoms was observed in the shallower littoral zone. These larger phytoplankters in the littoral
zone probably depend on nutrients from the Barguzin River. 相似文献
6.
In this study, the effects of carbon sources, abscisic acid (ABA) either alone or in combination with polyethylene glycol
(PEG) were evaluated on secondary embryo (SE) induction and maturation in rapeseed microspore-derived embryos (MDE) of cultivars
Global, PF704 and Option. Among various carbon sources tested (sucrose, glucose, fructose and sorbitol), the use of 0.3 M (300 mOsml−1) glucose and 0.2 M (200 mOsml−1) sorbitol in SE induction medium (for cultivars Global and PF704) and sorbitol at 0.2 and 0.3 M (200 and 300 mOsml−1, for cultivar Option), induced the highest secondary embryogenesis percentage (%SE). The highest number of SEs per each MDE
(SE/MDE) was observed with 0.2 M (200 mOsml−1) sorbitol in cultivar Global and with 0.3 M (300 mOsml−1) glucose in cultivars PF704 and Option. In another part of this study, the effect of different concentrations of ABA (0, 20, 40, 60, 80 and 100 μM) and
of a combined use of ABA (0 and 40 μM) and PEG 4000 or PEG 6000 at 15 g l−1 (3.75 and 2.5 mOsml−1, respectively) was examined on induction and maturation of SEs. In the first experiment, the use of ABA in SE induction medium
reduced the mean number of SE/MDE in the three studied cultivars, whereas use of 40–80 μM ABA in SE induction medium increased
the percentage of mature SEs in each cultivar. The combined use of PEG with or without ABA also reduced the mean number of
SE/MDE compared with control, but resulted in significant enhancement of the percentages of mature SEs for the three cultivars. 相似文献
7.
Guggulsterone, a hypolipidemic natural agent, is produced in resin canals of the plant Commiphora wightii. In this study, the stimulatory effects of growth retardants [ALAR (N,N-dimethylaminosuccinamic acid) and CCC (chlormequat chloride)] and fungal elicitor on guggulsterone accumulation in cell cultures
of C. wightii are reported. CCC at 1 mg l−1 enhanced guggulsterone content (~123 μg l−1) when added on the fifth day after inoculation, while ALAR at 2.5 mg l−1 increased guggulsterone content (~116 μg l−1) when added on the tenth day. In a two-stage fed-batch process, combined treatment with fungal elicitor and growth retardant
caused a significant increase (~353 μg l−1) in guggulsterone content in cell cultures after 17 days of growth. This represents an approximately fivefold increase over
the guggulsterone contents in initial cultures of this plant. 相似文献
8.
Bo Long Alex X. Niemiera Zhi-ying Cheng Chun-lin Long 《Plant Cell, Tissue and Organ Culture》2010,101(2):151-162
The effects of seed maturity, media type, carbon source, and organic nutrient additives on seed germination, protocorm development,
and plant growth of Paphiopedilum villosum var. densissimum Z. J. Liu et S. C. Chen were investigated. Micropropagation frequency was enhanced through the use of 200-day-old seed, Knudson
C (KC) medium, and the presence of both glucose and coconut milk in the medium. The effects of various plant growth regulators
on the frequency of shoot organogenesis in four Paphiopedilum species were also investigated. Explants of P. villosum var. densissimum and P. insigne (Lindl.) Stein incubated in the presence of 5 mg l−1 6-benzyladenine (BA) with 0.5 mg l−1 α-naphthalene acetic acid (NAA) and 0.2 mg l−1 BA with 0.1 mg l−1 NAA, respectively, showed a twofold increase in the frequency of shoot organogenesis. For explants of P. bellatulum (Rchb. f.) Stein and P. armeniacum S. C. Chen et F. Y. Liu, the combination of 5.5 mg l−1 BA with 0.5 mg l−1 NAA and 4 mg l−1 BA with 0.1 mg l−1 NAA, respectively, resulted in the highest frequencies of shoot organogenesis. 相似文献
9.
The algal, protozoan and metazoan communities within different drift-ice types (newly formed, pancake and rafted ice) and
in under-ice water were studied in the Gulf of Bothnia in March 2006. In ice, diatoms together with unidentified flagellates
dominated the algal biomass (226 ± 154 μg ww l−1) and rotifers the metazoan and protozoan biomass (32 ± 25 μg ww l−1). The under-ice water communities were dominated by flagellates and ciliates, which resulted in lower biomasses (97 ± 25
and 21 ± 14 μg ww l−1, respectively). The under-ice water and newly formed ice separated from all other samples to their own cluster in hierarchical
cluster analysis. The most important discriminating factors, according to discriminant analysis, were chlorophyll-a, phosphate and silicate. The under-ice water/newly formed ice cluster was characterized by high nutrient and low chlorophyll-a values, while the opposite held true for the ice cluster. Increasing trends in chlorophyll-a concentration and biomass were observed with increasing ice thickness. Within the thick ice columns (>40 cm), the highest
chlorophyll-a concentrations (6.6–22.2 μg l−1) were in the bottom layers indicating photoacclimation of the sympagic community. The ice algal biomass showed additional
peaks in the centric diatom-dominated surface layers coinciding with the highest photosynthetic efficiencies [0.019–0.032 μg C (μg Chl-a
−1 h−1) (μE m−2 s−1)−1] and maximum photosynthetic capacities [0.43-1.29 μg C (μg Chl-a
−1 h−1)]. Rafting and snow-ice formation, determined from thin sections and stable oxygen isotopic composition, strongly influenced
the physical, chemical and biological properties of the ice. Snow-ice formation provided the surface layers with nutrients
and possibly habitable space, which seemed to have favored centric diatoms in our study. 相似文献
10.
Luis Arigita Ma Jesús Cañal Ricardo Sánchez Tamés Aida González 《In vitro cellular & developmental biology. Plant》2010,46(3):312-322
In traditional in vitro culture, the low CO2 concentration inside the vessels restricts photosynthesis and necessitates the addition of sucrose to the culture medium
as the main energy source, thus bringing about changes in the absorption of mineral elements from the culture medium. In this
study, we investigated macronutrient absorption and sugar consumption in Actinidia deliciosa Chevalier Liang and Ferguson cv. Hayward (kiwi), cultured on medium supplemented with varying amounts of sucrose (0, 10,
and 20 g l−1) under both heterotrophy and autotrophy, flushed with different concentrations of CO2 (non-ventilation, 300, 600, and 2,000 μl l−1). In ventilated systems with 20 g l−1 of sucrose, sucrose absorption was less than under non-ventilation. The lowest rate of sucrose absorption was recorded when
the explants were cultured on medium supplemented with 20 g l−1 of sucrose and flushed with 600 μl l−1 CO2. Absorption of NO3
−, PO4
3−, and Mg2+ were high (maximum) at the end of the culture period (40 d) in explants flushed with 600 μl l−1 CO2 that have been cultured 20 d in the presence of sucrose and then transferred to a sucrose-free medium. These autotrophic
conditions promoted maximum plant growth in terms of both fresh and dry mass as well as the length and number of shoots and
leaves. The study shows that to maintain an optimum regime of mineral nutrition for prolonged culture of kiwi in vitro, an increased amount of these three ions should be supplemented in Murashige and Skoog’s medium. 相似文献
11.
Two heterotrophic As(III)-oxidizing bacteria, SPB-24 and SPB-31 were isolated from garden soil. Based on 16S rRNA gene sequence
analysis, strain SPB-24 was closely related to genus Bordetella, and strain SPB-31 was most closely related to genus Achromobacter. Both strains exhibited high As(III) (15 mM for SPB-24 and 40 mM for SPB-31) and As(V) (>300 mM for both strains) resistance.
Both strains oxidized 5 mM As(III) in minimal medium with oxidation rate of 554 and 558 μM h−1 for SPB-24 and SPB-31, respectively. Washed cells of both strains oxidized As(III) over broad pH and temperature range with
optimum pH 6 and temperature 42°C for both strains. The As(III) oxidation kinetic by washed cells showed K
m and V
max values of 41.7 μM and 1,166 μM h−1 for SPB-24, 52 μM and 1,186 μM h−1 for SPB-31. In the presence of minimal amount of carbon source, the strains showed high As(III) oxidation rate and high specific
arsenite oxidase activity. The ability of strains to resist high concentration of arsenic and oxidize As(III) with highest
rates reported so far makes them potential candidates for bioremediation of arsenic-contaminated environment. 相似文献
12.
Eutrophication of moderately deep Dutch lakes during the past century: flaws in the expectations of water management? 总被引:1,自引:0,他引:1
We studied the trophic development of the past 30–100 years in eight moderately deep Dutch lakes based on their sedimentary
fossil diatom assemblages. The dominant diatoms indicating meso- to eutrophic conditions were Aulacoseira subarctica, Cyclotella ocellata, C. cyclopuncta, C. meneghiniana, Puncticulata bodanica, Aulacoseira granulata, Cyclostephanos dubius, C. invisitatus, Stephanodiscus hantzschii, S. medius, and S. parvus. Ordination of diatom data separated the lakes into four groups according to their total phosphorus concentrations (TP),
water supply, water management, and origin. The first group consists of dike-breach lakes, which were in stable eutrophic
to hypertrophic conditions throughout the past century with diatom-inferred TP (DI-TP) concentrations of between 70 and 300 μg l−1. The main factors influencing these dike-breach lakes are river management, ground water supply of riverine origin, and local
land use. The second group are artificial lakes of fluctuating oligo- to mesotrophic conditions and DI-TP concentrations of
10–30 μg l−1. Only one of the artificial lakes showed a DI-TP increase due to changes in catchment agricultural practice. A third group
includes an artificial moat and an inland dike-breach lake with DI-TP concentrations of 50–100 μg l−1. The fourth group contains an individual dike-breach lake with stable mesotrophic conditions of 50 μg l−1 throughout the past century. Rather than showing a regional pattern, the studied lakes behave very individualistically with
regard to their trophic history, reflecting changes in the local hydrology and in their nutrient sources. 相似文献
13.
Neslihan Balkis 《Aquatic Ecology》2009,43(2):249-270
Seasonal changes in the microphytoplankton assemblages were examined in the coastal zone of Bozcaada Island with regard to
some major physical and chemical variables. Samples were collected from May 2000 to December 2001 at four stations. A total
of 108 dinoflagellates, 102 diatoms, 1 chrysophycean, 3 dictyochophycean, and 1 prasinophycean species were identified and
quantified during the study period. Diatoms and dinoflagellates were the most important in terms of species number and abundance.
The maximum values of total microphytoplankton were observed at 0.5 m depth (46.2 × 103 cells l−1 at st. 3) in May as this was the month when the diatom Pseudo-nitzschia pungens bloomed. Chlorophyll (chl) a concentration ranged between 0.08 (August) and 0.78 μg l−1 (February). May was another important month in which chlorophyll a increased (0.41–0.47 μg l−1). Species diversity values (H′log2) ranged from 1.66 bits (June, 20 m) to 4.11 bits (November, 0.5 m). The increase was attributed to a more balanced distribution
of abundance among species. The amounts of nitrate + nitrite (0.6−3.7 μg-at N l−1), phosphate (0.2−0.6 μg-at P l−1) and silicate (0.7−2.5 μg-at Si l−1) were recorded on each sampling occasion. Nutrient concentrations and chl a values of the research area were found to be poorer than those of the many other coastal areas in the northeastern Mediterranean.
The mean atomic ratio of nitrogen to phosphorus varied from 1.3 (June) to 12.9 (February). This ratio was lower than the Redfield
ratio of 16 for ocean phytoplankton, and phytoplankton was potentially limited by nitrogen for most of the months. The result
of this study confirms and emphasizes the oligotrophic nature of the eastern Mediterranean. 相似文献
14.
Summary The present study aimed to evaluate the response to salinity of Populus euphratica, which is more salt-resistant than other poplar cultivars, at the cellular level. To this purpose, callus was induced from
shoot segments of P. euphratica on Murashige and Skoog (MS) medium supplemented with 0.5 mg l−1 (2.2 μM) 6-benzyladenine (BA) and 0.5 mg l−1 (2.7 μM 1-naphthaleneacetic acid (NAA). Callus was transferred to MS medium supplemented with 0.25 mg l−1 (1.1 μM) BA and 0.5 mg l−1 NAA. The relative growth rate of callus reached a maximum in the presence of 50 mmol l−1 NaCl and growth was inhibited with increasing NaCl concentrations. Examination of the changes of osmotic substances under
salt stress showed that accumulation of proline, glycine betaine, and total soluble sugars increased with increasing salt
concentrations. The results indicate that the response of the callus of P. euphratica to salt stress is similar to that of the whole plant. 相似文献
15.
16.
Cell cultures of Commiphora wightii (Arnott.) Bhandari were grown in shake flasks and a bioreactor and an increase in guggulsterone accumulation up to 18 μg
l−1 was recorded in cells grown in the production medium containing a combination of sucrose:glucose (4% total), precursors (phenylalanine,
pyruvic acid, xylose, and sodium acetate), morphactin, and 2iP. A yield of 10 g l−1 biomass and ∼200 μg l−1 guggulsterone was recorded in a 3-l flask and in a 2-l stirred tank bioreactor compared with 6.6 g biomass and 67 μg l−1 guggulsterone in 250-ml flasks. Increased vessel size was correlated with increased biomass and guggulsterone accumulation.
2iP alone was not effective for biomass and guggulsterone accumulation in cell cultures of C. wightii. 相似文献
17.
We investigated the effects of limiting (1.96 × 10−9 mol l−1 total Cu, corresponding to pCu 14.8; where pCu = −log [Cu2+]) and toxic Cu concentrations up to 8.0 × 10−5 mol l−1 total Cu (equivalent to pCu 9.5) on growth rates and photosynthetic activity of exponentially grown Phaeocystis cordata, using batch and semi-continuous cultures. With pulse amplitude modulated (PAM) fluorometry, we determined the photochemical
response of P. cordata to the various Cu levels, and showed contrasting results for the batch and semi-continuous cultures. Although maximum photosystem
II (PSII) quantum yield (ΦM) was optimal and constant in the semi-continuous P. cordata, the batch cultures showed a significant decrease in ΦM with culture age (0–72 h). The EC50 for the batch cultures was higher (2.0 × 10−10 mol l−1, pCu9.7), than that for the semi-continuous cultures (6.3 × 10−11 mol l−1, pCu10.2). The semi-continuous cultures exhibited a systematic and linear decrease in ΦM as Cu levels increased (for [Cu2+] < 1.0 × 10−12 mol l−1, pCu12.0), however, no effect of high Cu was observed on their operational PSII quantum yield (Φ′M). Similarly, semi-continuous cultures exhibited a significant decrease in ΦM, but not in Φ′M, because of low-Cu levels. Thus, Cu toxicity and Cu limitation damage the PSII reaction centers, but not the processes downstream
of PSII. Quenching mechanisms (NPQ and Q
n) were lower under high Cu relative to the controls, suggesting that toxic Cu impairs photo-protective mechanisms. PAM fluorometry
is a sensitive tool for detecting minor physiological variations. However, culturing techniques (batch vs. semi-continuous)
and sampling time might account for literature discrepancies on the effects of Cu on PSII. Semi-continuous culturing might
be the most adequate technique to investigate Cu effects on PSII photochemistry. 相似文献
18.
In vitro regeneration and morphogenesis studies in common bean 总被引:1,自引:0,他引:1
Kingdom Kwapata Robab Sabzikar Mariam B. Sticklen James D. Kelly 《Plant Cell, Tissue and Organ Culture》2010,100(1):97-105
An efficient protocol for high frequency in vitro regeneration of multiple shoots and somatic embryos from the embryonic axis
of common bean (Phaseolus vulgaris) was developed. Ten common bean cultivars representing a wide range of diversity among current commercial market classes
were used for in vitro regeneration evaluation in our study. These cultivars were tested on 63 different media formulations
consisting of combinations of cytokinins, namely benzyladenine (BA) and thidiazuron (TDZ) at concentration levels of 0.0,
1.0, 2.5, 5.0 and 10.0 mg l−1 and auxin, namely naphthalene acetic acid (NAA) and indole-3-acetic acid (IAA) at concentration levels of 0.0, 0.05, 0.1
and 1.0 mg l−1. P. vulgaris cv. Olathe pinto bean performed the best producing over 20 multiple shoots per explant while cv. Condor black bean was the
poorest with nine multiple shoots per explant. The optimum media for regeneration of multiple shoots was 4.4 mg l−1 Murashige and Skoog (MS) containing 2.5 mg l−1 BA and 0.1 mg l−1 IAA supplemented with 30 mg l−1 silver nitrate. Adventitious shoots and somatic embryos were regenerated on 4.4 mg l−1 MS medium containing 1 mg l−1 TDZ and 0.05 mg l−1 NAA supplemented with 30 mg l−1 silver nitrate or activated charcoal. Efficient and effective rooting of plantlets was achieved by dipping the cut end base
of in vitro regenerated shoots in 1.0 mg l−1 indole-3-butyric acid (IBA) solution and culturing on media containing 4.4 mg l−1 MS supplemented by 0.1 mg l−1 IAA, NAA or IBA. 相似文献
19.
Stimulation of menthol production in <Emphasis Type="Italic">Mentha piperita</Emphasis> cell culture 总被引:1,自引:0,他引:1
Amrita Chakraborty Sharmila Chattopadhyay 《In vitro cellular & developmental biology. Plant》2008,44(6):518-524
Plant cell culture provides an alternative means for producing secondary metabolites. In this study, experiments were carried
out to study the impact of several parameters, independently and in combination, on the stimulation of menthol production
in the cell suspension culture of Mentha piperita. Callus was obtained from leaf segments of in vitro grown plantlets on Murashige and Skoog (MS) medium supplemented with 0.2 mg l−1of 2,4-dichlorophenoxy acetic acid to initiate cell suspension culture. This culture was maintained in half-strength MS medium
supplemented with 0.2 mg l−1of 2,4-dichlorophenoxy acetic acid at 15 d interval and used for further studies. Precursor feeding alone, i.e., menthone,
at 35 μM concentration showed slightly improved productivity. γ-Cyclodextrin alone at 60 μM concentration and in combination
with menthone feeding at 35 μM increased menthol yield up to 92 and 110 mg l−1 in comparison to 77 mg l−1 of control culture. Synergistic potentiation effect of menthone feeding at 35 μM and γ-cyclodextrin at 60 μM treatment followed
by in situ adsorption with RP-8 also showed potential stimulation of menthol production in M. piperita cell culture. Fungal elicitor treatment showed enhanced production level up to 140.8 mg l−1 in comparison to that of control. Further studies were carried out with the establishment of Agrobacterium tumefaciens (Ach5) gall-mediated calli, and consequently, cell suspension culture and results showed the significant enhancement of menthol
yield up to 278 mg l−1.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
20.
A. V. Loskutov G.-Q. Song K. C. Sink 《In vitro cellular & developmental biology. Plant》2008,44(4):239-245
Callus selection (CS) and the flamingo-bill explant (FB) methods were evaluated for efficacy in transformation for celery.
Agrobacterium tumefaciens strains EHA105 and GV3101, each with the bar gene under the promoters NOS (pGPTV-BAR) or 35S (pDHB321.1), were used. Leaf explants were inoculated and co-cultivated for
2 d in the dark. Calluses emerged on the explants on callus medium (C), Murashige and Skoog (MS) medium + 2,4-Dichlorophenoxyacetic
acid (2,4-D) (2.3 μM) + kinetin (2.8 μM) + timentin (300 mg·l−1). Calluses 4- to 6-wk-old were selected for glufosinate (GS) resistance by a two step method. First, calluses were transferred
to C medium + GS 0.35, 0.5, 1, 2, 5, or 10 mg·l−1; calluses formed only with 0, 0.35 and 0.5 mg·l−1 GS. All growing calluses from 0 and 0.35 mg·l−1 and a few from 0.5 mg·l−1, were divided and placed back on C + GS 0.35–0.5 mg·l−1 for another 5–6 wk. Second, tolerant clones were again divided and placed on C + GS 1–50 mg·l−1. When cultivar XP85 was inoculated with both strains, using pGPTVBAR, 19 glufosinate resistant (GR) callus clones were selected,
but shoots regenerated only for strain EHA105 inoculations. When both of the strains (each with pDHB321.1) were inoculated
on cv. XP166, 3 and 12 GR calluses occurred for EHA105 and GV3101, respectively. Using CS, a total of 34 GR callus clones
were selected, and shoots were regenerated from over 50% of them on Gamborg B5 medium + 6-(γ, γ-dimethylallylamino) purine
2ip (4.9 μM) + naphthaleneacetic acid (NAA; 1.6 μM) and rooted on MS in 5–6 mo total time. Conversely, using FB with inoculation
by GV3101/pDHB321.1 on cv. XP166 yielded putative transgenic celery plants confirmed by polymerase chain reaction (PCR) in
just 6 wk. Transformation of the bar gene into celery was confirmed by PCR for 5 and 6 CS and FB lines, respectively. Southern blot analyses indicated 1–2 copies
in CS lines and 1 copy in FB lines. Herbicide assays on whole plants with 100 and 300 mg·l−1 glufosinate indicated a range of low to high tolerance for lines derived by both methods. The bar gene was found to be Mendelian inherited in one self-fertile CS derived line. 相似文献