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1.
Alien plant species, such as Caulerpa racemosa var. cylindracea, that invade Mediterranean marine vegetated habitats can affect habitat structure. In turn, changes in habitat structure
may affect the associated invertebrate assemblages, either through changes in habitat selection or as a result of altered
predation efficiency. In order to test for effects of changes in habitat structure resulting from colonization by C. racemosa on prey availability for predators, the importance of amphipods as a trophic resource in natural vegetated habitat was first
assessed, and later experiments were undertaken to assess the effects of the alien alga on predation by Thalassoma pavo of two dominant amphipods: Elasmopus brasiliensis (Gammaridea) and Caprella dilatata (Caprellidea). Laboratory experiments were conducted in separate aquaria with five vegetation habitat types: Halopteris scoparia, Jania rubens, C. racemosa without detritus, C. racemosa with detritus, Cymodocea nodosa, together with controls. The vegetation was first defaunated, and then 30 amphipods were introduced to each aquarium and
exposed to a single Thalassoma pavo individual for 1 h, after which the fish’s gut contents were examined. Consumption (per fish per hour) of caprellids (11.7 ± 1.4)
was higher overall than that of gammarids (8.7 ± 1.5) and likely reflects different microhabitat use by amphipods, which affects
susceptibility to predators. Consumption of amphipods also varied by habitat type. The highest predation rate was found in
the C. nodosa habitat (12.7 ± 2.19) and the lowest in the C. racemosa habitats with detritus (4.1 ± 1.78) and without detritus (5.2 ± 0.55), which did not differ. The pattern of predation across
habitats, however, was similar for both caprellid and gammarid amphipods, indicating a more general effect of habitat on amphipod
predation. Our findings showed that invasive species such as C. racemosa can decrease feeding by predators such as T. pavo. Changes in predator–prey interactions could have consequences for food web support in the Mediterranean. 相似文献
2.
Agbeko Kodjo Tounou Christiann Kooyman Ouro Kobi Douro-Kpindou Hans Michael Poehling 《BioControl》2008,53(5):813-828
Field trials were conducted to evaluate the efficacy of wheat bran bait formulations of Paranosema locustae and Metarhizium anisopliae for controlling grasshoppers in southeast Niger. Treatments consisted of wheat bran baits mixed with M. anisopliae, P. locustae + M. anisopliae or with P. locustae spores and P. locustae + sugar. Oedaleus senegalensis, Pyrgomorpha cognata and Acrotylus blondeli were the predominant species at the time of application representing ca. 94% of the total population. Bran application was
done when O. senegalensis (ca. 75% of the population) was at its early developmental stages, with first, second and third instars accounting for 64–85%.
Grasshopper population reduction, P. locustae prevalence and level of infections in the predominant species were monitored. Manual application of P. locustae and M. anisopliae formulated in wheat bran has proven to induce consistent pathogen infection in grasshopper populations. Population density
over the three weeks monitoring, typically decreased by 44.7 ± 6.9%, 52.8 ± 8.4%, 73.7 ± 5.5% and 89.1 ± 1.8% in P. locustae, P. locustae + sugar, M. anisopliae and P. locustae + M. anisopliae treated plots respectively. Paranosema locustae prevalence in surviving adult grasshoppers at 28 after application was 48.1 ± 2.3%, 28.9 ± 4.8% and 27.4 ± 3.7%, with infection
level of 6.2 ± 0.8 × 106, 2.3 ± 0.3 × 104 and 2.1 ± 0.3 × 103 spores mg−1 host weight in O. senegalensis, A blondeli and P. cognate respectively. Other species that each accounted for <2% of the community, namely Aiolopus thalassinus, A. simulatrix, Acorypha glaucopsis, Acrotylus patruelis, Anacridium melanorhodon, Diabolocatantops axillaris, Kraussaria angulifera and Schistocerca gregaria were found to show sign of infection. The results from this study suggest that wheat bran application of M. anisopliae and P. locustae alone or in combination, targeting early instars grasshopper could be a valuable option in grasshopper control programs. 相似文献
3.
The predatory copepod Acanthocyclops americanus is commonly found in shallow ponds and lakes in Mexico. We tested the survivorship and reproduction-related variables of
this copepod, isolated from Lake Huetzalin (Xochimilco, Mexico City), on four mixed diets comprising two algal concentrations
(0.8 × 106 and 1.6 × 106 cells ml−1 of Scenedesmus acutus) and two rotifer densities (1 and 8 ind. ml−1 of Brachionus havanaensis). Survivorship patterns of naupliar and adult stages of A. americanus were evaluated at 24 ± 1°C. The demography experiments were initiated with five females and five males (1:1 ratio, 5th copepodites)
into each of the 16 test [= 4 diet combinations × 4 replicates (cohorts)] jars containing 50 ml medium and with one of the
chosen algal-rotifer diets. Data on the survival of naupliar and copepodites (up to V) showed a high death rate (80%) in A. americanus by the time nauplii reached the adult stage. The duration of developmental time for nauplii and the copepodite V (C-V) was
about 28 days by which time A. americanus became adults. Food combination had a significant effect on both survival and duration of the naupliar and C-V but not on
the development time in C-I, C-II, C-III, and C-IV. Naupliar stages showed highest life expectancy at low food levels (rotifers
or alga). Adult male and female copepods showed better survival under higher availability of rotifers in the medium, while
higher algal density resulted in steep mortality during the first days. Average adult lifespan and life expectancy of A. americanus varied from 19 to 23 days, depending on the diet combination. Age-specific reproductive output (m
x
) of female A. americanus showed low reproduction (<10 offspring per female on any given day) when raised on low rotifer density, regardless of the
algal concentration. On the other hand, enhanced offspring production (average of about 50 nauplii per female) was recorded
when the rotifer density was higher (i.e., 8 ind. ml−1). Gross and net reproductive rates varied from 48 to 438 and 27 to 318 offspring per female, respectively. In general, higher
availability of rotifers in the medium resulted in higher (8–10 times as compared to those in low rotifer density) gross and
net reproductive rates. There was no significant difference in the generation time (13–14 days) in relation to the diet combination.
The rate of population increase (r) (range: 0.29–0.69 per day) increased with greater abundance of B. havanaensis in the medium. Thus, our study showed that inclusion of animal protein in the diet is necessary for high population growth
rates of A. americanus. 相似文献
4.
We have investigated the antioxidant activity of protein hydrolysates prepared from backbones of two commercially important
fishes; seela (Sphyraena barracuda) and ribbon fish (Lepturacanthus savala). Pepsin and trypsin hydrolysates were found more potent to inhibit lipid peroxidation in case of ribbon and seela fish respectively
and were further purified by using fast protein liquid chromatography on anion exchange and gel filtration chromatography.
The active peaks after gel filtration chromatography of seela fish was able to scavenge 2,2-diphenyl-1-picryhydrazyl and hydroxyl
radicals by 61 ± 2.3 and 58.7 ± 2.3% and ribbon fish hydrolysate by 60.0 ± 2.6 and 55.6 ± 1.8% as measured by ESR spectroscopy.
And the active fractions showed presence of both essential and non-essential amino acids with high percentages of arginine
(11.95 and 12.76%) and lysine (13.49 and 13.89%). 相似文献
5.
Shail Singh B. B. Singh R. Chandra D. K. Patel V. Rai 《World journal of microbiology & biotechnology》2009,25(10):1821-1828
The consortium of Bacillus cereus (DQ002384), Serratia marcescens (AY927692) and Serratia marcescens (DQ002385) were used for pentachlorophenol (PCP) degradation. The consortia showed better overall removal efficiencies than
single strains by utilization of PCP as a carbon and energy source confirmed by pH dependent dye indicator bromocresol purple
(BCP) in mineral salt media (MSM). Mixed culture was found to degrade up to 93% of PCP (300 mg/l) as compared to single strains
(62.75–90.33%), at optimized conditions (30 ± 1°C, pH 7 ± 0.2, 120 rpm) at 168 h incubation. PCP degradation was also recorded
at 20°C (62.75%) and 37°C (83.33%); pH 6 (70%) and pH 9 (75.16%); 50 rpm (73.33%) and 200 rpm (91.63%). The simultaneous release
of chloride ion up to 90.8 mg/l emphasized the bacterial dechlorination in the medium. GC–MS analysis revealed the formation
of low molecular weight compound, i.e., 6-chlorohydroxyquinol, 2,3,4,6-tetrachlorophenol and tetrachlorohydroquinone, from
degraded sample as compared to control. 相似文献
6.
7.
Pteromalus cerealellae (Ashmead) (Hymenoptera: Pteromalidae) is an ectoparasitoid of several stored-product insect pests. Very little information
has been published on its biology and development in host larvae, which typically are concealed within seeds. We documented
the development of P. cerealellae within fourth instar larvae of its concealed host, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) infesting cowpea seeds. The preimaginal life stages of the parasitoid were characterized
for the first time using morphological structures revealed by microscopic techniques including scanning electron microscopy. Pteromalus cerealellae produces hymenopteriform eggs and larvae. Eggs hatch into 13-segmented first instar larvae with peripneustic condition of
spiracles. The larvae have simple, tusk-like mandibles, whereas the mandibles of the pupae and the adults are of the conventional
toothed types. Using statistical analyses of the sizes of the larval mandibles and head capsules in conjunction with reliable
characters such as the number of exuviae on the body of parasitoid larvae, cuticular folding, and excretion of the meconium,
we recorded four larval instars for P. cerealellae. The data showed significant positive correlations between larval mandible lengths and widths of larval head capsules, as
well as between mandible lengths and larval instars, suggesting that mandible length is a good predictor of the number of
instars in P. cerealellae. Developmental time from egg to adult emergence was ∼12 d for females and ∼11 days for males at 30 ± 1°C, 70 ± 5% r.h. and
12L:12D photoperiod. 相似文献
8.
Unfed adult Amblyomma americanum were exposed to the entomopathogenic fungus Beauveria bassiana. Ticks exposed to the fungus exhibited reduced survival and increased water loss as indicated by change in weight. Treated
ticks survived 7.2 ± 0.22 days (mean ± SE) and controls survived 17.9 ± 0.73 days (P = 0.01; df = 57). At death, ticks exposed to the fungus had lost 25.2 ± 0.84% of their starting weight; control ticks had lost 14.1 ± 0.85%
of their starting weight (P = 0.01; df = 96). Water loss was highest immediately following inoculation, although losses continued to be higher than in uninoculated
ticks. This suggests that fungal penetration causes sufficient cuticle damage to cause desiccation, although other water-loss
avenues exist, including increased time of spiracular opening. Additionally this study did not eliminate the possibility of
a negative impact on water vapor uptake. This is the first study to investigate the effect of an entomopathogenic fungus on
the water balance of a tick. 相似文献
9.
The host-specificity and biological traits of Gonatocerus deleoni Triapitsyn, Logarzo & Virla (Hymenoptera: Mymaridae), a potential candidate for biological control of the glassy-winged sharpshooter
(GWSS), Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae), were determined under laboratory conditions. G. deleoni is a solitary egg parasitoid native to Argentina, originally reared from sentinel eggs of Tapajosa rubromarginata (Signoret) (Cicadellidae). With GWSS as a fictitious host, G. deleoni’s average development time from oviposition to adult emergence was 18.8 ± 1.4 days, with males developing faster than females
(18.0 ± 1.3 days, males; 19.0 ± 1.3 days, females). The average parasitism rate on 1–8-day-old eggs was 45.7% but this was
significantly affected by the age of the egg, ranging from 1.4% to 69.9% (egg ages 8 and 3, respectively). The average sex
ratio was 0.34 (percent males) and sex ratio was not significantly affected by egg age. G. deleoni was able to develop in eggs of GWSS and Homalodisca liturata Ball (both in the tribe Proconiini), but was unable to develop on eggs of Graphocephala atropunctata (Signoret) (different tribe, same subfamily) or Erythroneura elegantula Osborn (different subfamily). 相似文献
10.
This paper presents the results of a demographic analysis of 22 years of data recorded on a colony of tufted capuchin monkeys
(Cebus apella) in captivity at the CNR Primate Centre (Rome, Italy). Information is provided on reproduction, sex ratio, inter-birth interval
(IBI), seasonality, and body weight. From 1984 to 2006, 46 live births were recorded. There were births in almost all months
of the year, but a higher frequency was observed during spring and summer (71.1%). The sex ratio was 1:1 M:F for newborns
and 1:1.06 M:F for surviving offspring. At birth, infants’ average weight was 238.13 ± 37.51 g, i.e. 250 ± 56.79 g for males
and 231 ± 26.08 g for females. Age at first birth for females ranged from 4.9 to 7 years (n = 9), while males achieved first paternity between the ages of 5 and 9.2 years (n = 6). Only one pair of twins was recorded during this period. For females, the mean IBI was 17.88 ± 1.84 months, when they
reared infants, and 12.70 ± 1.73 months, when they did not rear offspring. Infant mortality within the first 2 months was
28.3%. 相似文献
11.
Fernando G. Brun Elleke van Zetten Eva Cacabelos Tjeerd J. Bouma 《Helgoland Marine Research》2009,63(1):19-25
Seagrasses are well known ecosystem engineers that can significantly influence local hydrodynamics and the abundance and biodiversity
of macrobenthic organisms. This study focuses on the potential role of the seagrass canopy structure in altering the abundance
of filter-feeding organisms by modifying the hydrodynamic driven food supply. We quantified the effect of two ecosystem engineers
with contrasting canopy properties (i.e. Zostera noltii and Cymodocea nodosa) on the food intake rate of a suspension-feeding bivalve Cerastoderma edule living in these seagrass meadows. Field experiments were carried out in two seagrass beds (Z. noltii and C. nodosa) and bare sediment, located on sandflat characterised by a relatively high hydrodynamic energy from waves and currents. Results
demonstrated that the filter-feeding rate was almost twofold increased when C. edule was inhabiting Z. noltii meadows (1.10 ± 0.24 μg Chl g Fresh Weight−1) when compared to cockles living on the bare sediment (0.65 ± 0.14 μg Chl g FW−1). Intermediate values were found within C. nodosa canopy (0.97 ± 0.24 μg Chl g FW−1), but filter feeding rate showed no significant differences with values for Z. noltii meadows. There were no apparent correlations between canopy properties and filter-feeding rates. Our results imply that food
refreshment within the seagrass canopies was enough to avoid food depletion. We therefore expect that the ameliorated environmental
conditions within vegetated areas (i.e. lower hydrodynamic conditions, higher sediment stability, lower predation pressure…)
in combination with sufficient food supply to prevent depletion within both canopies are the main factors underlying our observations. 相似文献
12.
Daisuke Sugimori 《Applied microbiology and biotechnology》2009,82(2):351-357
To develop a microbial treatment of edible oil-contaminated wastewater, microorganisms capable of rapidly degrading edible
oil were screened. The screening study yielded a yeast coculture comprising Rhodotorula pacifica strain ST3411 and Cryptococcus laurentii strain ST3412. The coculture was able to degrade efficiently even at low contents of nitrogen ([NH4–N] = 240 mg/L) and phosphorus sources ([PO4–P] = 90 mg/L). The 24-h degradation rate of 3,000 ppm mixed oils (salad oil/lard/beef tallow, 1:1 w/w) at 20°C was 39.8% ± 9.9% (means ± standard deviations of eight replicates). The highest degradation rate was observed at
20°C and pH 8. In a scaled-up experiment, the salad oil was rapidly degraded by the coculture from 671 ± 52.0 to 143 ± 96.7 ppm
in 24 h, and the degradation rate was 79.4% ± 13.8% (means ± standard deviations of three replicates). In addition, a repetitive
degradation was observed with the cell growth by only pH adjustment without addition of the cells. 相似文献
13.
González-Gómez R Otero-Colina G Villanueva-Jiménez JA Peña-Valdivia CB Santizo-Rincón JA 《Experimental & applied acarology》2012,56(3):261-270
A crude oil extract of neem seed (Azadirachta indica, Sapindales: Meliaceae) was evaluated for repellency on Varroa destructor Anderson and Trueman. Burgerjon’s tower was used to spray worker bee pupae with 0.0, 0.3, 0.7, 1.3, 2.6, 5.3, 10.6 and 21.1%
neem extract concentrations. Sprayed pupae were attached to observation arenas and incubated at 32 ± 2°C and 70 ± 10% RH.
The ability of V. destructor to locate and feed on treated and untreated pupae was monitored from 30 min to 72 h after spray. Higher and more stable repellency
was achieved with 2.6, 5.3, 10.6 and 21.1% neem extract. At the highest concentration, 98% of V. destructor were prevented to settle on bee pupae, resulting in 100% V. destructor mortality at 72 h. 相似文献
14.
The FPS1 gene coding for the Fps1p aquaglyceroporin protein of an industrial strain of Saccharomyces cerevisiae was disrupted by inserting CUP1 gene. Wild-type strain, CE25, could only grow on YPD medium containing less than 0.45% (v/v) acetic acid, while recombinant
strain T12 with FPS1 disruption could grow on YPD medium with 0.6% (v/v) acetic acid. Under 0.4% (v/v) acetic acid stress (pH 4.26), ethanol production
and cell growth rates of T12 were 1.7 ± 0.1 and 0.061 ± 0.003 g/l h, while those of CE25 were 1.2 ± 0.1 and 0.048 ± 0.003 g/l h,
respectively. FPS1 gene disruption in an industrial ethanologenic yeast thus increases cell growth and ethanol yield under acetic acid stress,
which suggests the potential utility of FPS1 gene disruption for bioethanol production from renewable resources such as lignocelluloses. 相似文献
15.
Syed G. Dastager C. K. Deepa Ashok Pandey 《World journal of microbiology & biotechnology》2011,27(2):259-265
A potential bacterial strain designated as NII-0928 isolated from Western ghat forest soil with multiple plant growth promoting attributes, and it has been identified and characterized. Plant growth promoting
traits were analyzed by determining the P-solubilization efficiency, Indole acetic acid production, HCN, siderophore production
and growth in nitrogen free medium. It was able to solubilize phosphate (76.6 μg ml−1), and produce indole acetic acid (58.9 μg ml−1) at 28 ± 2°C. Qualitative detection of siderophore production and HCN were also observed. At 5°C it was found to express
all the plant growth promotion attributes except HCN production. The ability to colonize roots is a sine qua non condition
for a rhizobacteria to be considered a true plant growth-promoting rhizobacteria (PGPR). 16S rRNA gene sequencing reveals
the identity of the isolate as Serratia nematodiphila with which it shares highest sequence similarity (99.4%). Seed bacterization with black pepper cuttings in greenhouse trials
using Sand: Soil: FYM with three individual experimental sets with their respective control showed clearly the growth promoting
activity. Hence, Serratia nematodiphila NII-0928 is a promising plant growth promoting isolate showing multiple PGPR attributes that can significantly influence
black pepper cuttings. The result of this study provides a strong basis for further development of this strain as a bioinoculants
to attain the desired plant growth promoting activity in black pepper growing fields. 相似文献
16.
A. Karthikeyan J. Shilpha S. Karutha Pandian M. Ramesh 《Plant Cell, Tissue and Organ Culture》2012,109(1):153-165
A reproducible and highly efficient protocol for Agrobacterium tumefaciens-mediated transformation of indica rice (Oryza sativa L. subsp. indica cv. ADT 43) was established. Prior to transformation, embryogenic callus were induced from mature seeds incubated on Linsmaier
and Skoog (LS) medium supplemented with 2.5 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.0 mg l−1 thiamine-HCl. Callus, intact mature seeds, and other in vitro derived explants (leaf bases, leaf blades, coleoptiles, and
root-tips) were immersed in a bacterial suspension culture of A. tumefaciens strain EHA 105, OD600 of 0.8, and co-cultivated on LS medium for 2 days in the dark at 25 ± 2°C. Based on GUS expression
analysis, 10 min incubation time of explants on a co-cultivation medium containing 100 μM acetosyringone was optimum. Following
β-glucuronidase (GUS) assay and polymerase chain reaction (PCR) analysis, transformants were identified. Stable integration
of the transgene was confirmed in four putatively transformed T0 plants by Southern blot analysis. The copy number of the transgene in these lines, one to two, was then determined. Among
the observations made, necrosis of co-cultivated explants was a problem, as well as sensitivity of callus to Agrobacterium infection. Levels of necrosis could be minimized following co-cultivation of explants in a medium consisting of 30% LS and
containing 10 g l−1 (14), polyvinyl pyrrolidone, 10% coconut water, and 250 mg l−1 timentin (15:1). This latter medium also increased the final transformation efficiency to 15.33%. 相似文献
17.
Serena Santolamazza-Carbone Montserrat Pestaña Nieto Rosa Pérez Otero Pedro Mansilla Vázquez Adolfo Cordero Rivera 《BioControl》2009,54(2):195-209
We investigated the effects of temperature, photoperiod, food and host availability, and body size on the overwintering abilities
of the egg parasitoid Anaphes nitens Girault (Hymenoptera, Mymaridae) under natural conditions. Seven groups of eighty females received one of four treatments
(n = 20): (i) honey and hosts, (ii) water and hosts, (iii) honey, or (iv) water. Seven groups of forty males received only honey
or water (n = 20). To test if short day-length is the main cue for larval dormancy, the experiment was replicated inside a climate chamber
at 20°C and under a winter photoperiod. A. nitens overwinters because of quiescence or oligopause inside the hosts and increased adult longevity. Mean pre-emergence mortality
was up to 26% indoors and 15.2% outdoors, males being more affected. Development time had a significant and positive effect
on body size. Honey-fed females without hosts had the highest longevity (53 days). Mother’s diet and size affected development
time, body size, longevity, and fecundity of the progeny. The results confirm the good adaptation of the parasitoid to the
environmental conditions of NW Spain and its ability to synchronize its life cycle with the phenology of the host.
Handling editor: Drik Babendreier. 相似文献
18.
Hai-Nan Su Bin-Bin Xie Xiu-Lan Chen Jin-Xia Wang Xi-Ying Zhang Bai-Cheng Zhou Yu-Zhong Zhang 《Journal of applied phycology》2010,22(1):65-70
Allophycocyanin (APC) is a minor component of phycobiliproteins in cyanobacteria and red algae. This paper describes a simple
and inexpensive extracting method for isolating APC from Spirulina (Arthrospira) platensis with high efficiency. The crude phycobiliprotein extract was pretreated by ammonium sulfate fractionation. Then, by adding
hydroxylapatite into crude phycobiliprotein extract dissolved in 20 mM phosphate buffer (pH 7.0), APC was selectively adsorbed
by hydroxylapatite but C-phycocyanin (C-PC) was not. The hydroxylapatite was collected and APC was extracted from the crude
phycobiliprotein extract. Then, the enriched APC was washed off from the hydroxylapatite using 100 mM phosphate buffer (pH 7.0).
In this simple extracting method it was easy to remove C-PC and isolate APC in large amounts. The absorbance ratio A
650/A
280 of extracted APC reached 2.0. The recovery yield was 70%, representing 4.61 mg · g−1 wet weight. The extracted APC could be further purified by a simple anion-exchange chromatography with a pH gradient from
5.6 to 4.0. The absorbance ratio A
650/A
280 of the purified APC reached 5.0, and the overall recovery yield was 43%, representing 2.83 mg · g−1 wet weight. Its purity was confirmed by native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate-PAGE. 相似文献
19.
D. C. Peñalva-Arana Kenneth Forshay Pieter T. J. Johnson J. R. Strickler Stanley I. Dodson 《Hydrobiologia》2011,668(1):147-154
Zooplankters are hosts to numerous endo- and ectoparasites, some of which have dramatic impacts on their hosts. Epizootics
on zooplankton are probably more widespread in lake systems than it is currently known, and few studies have explored the
direct and indirect importance of parasitism in aquatic food webs. In addition, our understanding of the sublethal effects
of parasitic infections on host organisms and populations is limited. We used a novel electro-chemical based technique to
measure in the outflow of the feeding current changes in the beat rate of the thoracic appendages in female Daphnia pulicaria. We observed simultaneously the heart rates and compared chytrid infected animals with uninfected gravid and non-gravid ones.
We found in uninfected animals a thoracic beat rate of 3.81 ± 018 Hz and a heart rate of 4.67 ± 0.42 Hz. Gravid daphnids had
a 14% lower thoracic beat rate (3.27 ± 0.30 Hz) than non-gravid females while the heart rate did not significantly differ
(4.48 ± 0.28 Hz). In contrast, infected animals showed a 22% lower thoracic beat rate (2.96 ± 0.47 Hz) and a 36% lower heart
rate (2.98 ± 0.5 Hz) when compared with uninfected non-gravid females. We discuss the ways Daphnia are affected by Polycaryum leave infections on the individual and population level. 相似文献
20.
A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献