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1.
V. A. Kulikova V. A. Omel'yanenko N. A. Aizdaicher 《Russian Journal of Marine Biology》2000,26(5):367-369
The reproduction and development of the prosobranch gastropodAlaba vladivostokensis Bartsch were studied. In Vostok Bay,A. vladivostokensis reproduces in the warmest season at water temperatures of 19–23°C. The females lay egg masses in the shape of flat, coiled
bands on eelgrass leaves and on sargosso thalluses. The total period of development from egg laying to larval settling takes
25–27 days. The reproduction and development patterns and larval morphology ofA. vladivostokensis are similar to that ofAustralaba picta (A. Adams), which inhabits the coast of Japan. It is suggested that the population ofA. vladivostokensis in Peter the Great Bay should considered as part of the wide geographical range ofA. picta. 相似文献
2.
Abundance of picophytoplankton in the halocline of a meromictic lake, Lake Suigetsu, Japan 总被引:1,自引:0,他引:1
Mari Okada Yukiko Taniuchi Akio Murakami Shinichi Takaichi Shinya Ohtake Kaori Ohki 《Limnology》2007,8(3):271-280
Numerous (0.5 to 4.8 × 105 cells/ml), small phytoplankton (smaller than 0.5–1 × 1–2 μm in cell size, picophytoplankton) were distributed in the halocline
(depth 2–12 m, 4–14 practical salinity units) of the saline meromictic lake, Lake Suigetsu (35°35′ N, 135°52′ E), located
in the central part of the coast of Wakasa Bay along the Japan Sea in Fukui Prefecture, Japan. Vertical distribution of phytoplankton
revealed that the maximum number of picophytoplankton was always observed near or a little deeper than the oxic-anoxic boundary
layer (depth 5–6 m); they were dominant phytoplankton in the water layer deeper than the oxic-anoxic boundary from July to
late September 2005. Spectral analysis of autofluorescence emitted from the particle fractions smaller than 5 μm measured
with a spectrofluorometer and from individual cells measured with a microscope photodiode array detector revealed that the
major component of picophytoplankton was phycoerythrin-rich, unicellular cyanobacteria (picocyanobacteria). Eukaryotic phytoplankton
about 2.5 μm in diameter were also found, but the numbers were low. Fluorescence intensity of chlorophyll a at 685 nm (room temperature) emitted from the particle fractions smaller than 5 μm was increased by the addition of 3-(3,4-dichlorophenyl)-1,1-dimethylurea.
These observations indicated that at least some picophytoplankton had a functional photosystem II in the halocline where sulfide,
the potential inhibitor of oxygenic photosynthesis, was always present. The large abundance together with their physiological
potency suggest that picophytoplankton are one of the important primary producers in the halocline of Lake Suigetsu.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users. 相似文献
3.
Bruce Vondracek Wayne A. Wurtsbaugh Joseph J. Cech 《Environmental Biology of Fishes》1988,21(1):45-57
The allocation of energy to growth and reproduction, in relation to temperature and food availability, was investigated in
laboratory experiments with the mosquitofish,Gambusia affinis. At constant temperature of 20, 25 and 30°C and ad libitum feeding, specific growth rates increased with increasing temperature
at 1.7, 3.1 and 3.4% dry mass day−1, respectively. Growth rates in a cycling temperature regime (20–30°C,
) were faster than in a 25°C constant temperature. As temperature increased from 20 to 30°C, mean age at first reproduction
decreased from 191 to 56 days and brood size and mass of offspring increased significantly. Interbrood interval was also temperature
dependent; estimates at 25 and 30°C for females >1000 mg were 22.6 and 18.6 days, respectively. Interbrood interval could
not be calculated at 20°C. Although fitness was highest at 30°C, females at 25°C invested a greater proportion of surplus
energy (growth and reproduction) to reproduction (38%) than at 20 (17%) or 30°C (36%) during the 32-week study. Fish at cooler
temperatures began reproduction at a smaller size.
Where rations were controlled at low, medium, and ad libitum levels, somatic and gonadal growth increased with increasing
temperatures and food availability. The proportion of energy invested in reproduction was highest at 25°C for each comparable
ration level. Calculated energy budgets indicated that over the 10-week study, 17–22% of the food energy was invested in growth,
0–7% in reproduction, and 75–83% in respiration and excretory losses, depending on feeding and temperature conditions. 相似文献
4.
Isolation and Characterization of Acetate-Utilizing Anaerobes from a Freshwater Sediment 总被引:1,自引:0,他引:1
Acetate-degrading anaerobic microorganisms in freshwater sediment were quantified by the most probable number technique. From
the highest dilutions a methanogenic, a sulfate-reducing, and a nitrate-reducing microorganism were isolated with acetate
as substrate. The methanogen (culture AMPB-Zg) was non-motile and rod-shaped with blunted ends (0.5–1 μm × 3–4 μm long). Doubling
times with acetate at 30–35°C were 5.6–8.1 days. The methanogen grew only on acetate. Analysis of the 16S rRNA sequence showed
that AMPB-Zg is closely related toMethanosaeta concilii. The isolated sulfate-reducing bacterium (strain ASRB-Zg) was rod-shaped with pointed ends (0.5–0.7 μm × 1.5–3.5 μm long),
weakly motile, spore forming, and gram positive. At the optimum growth temperature of 30°C the doubling times with acetate
were 3.9–5.3 days. The bacterium grew on a range of organic acids, such as acetate, butyrate, fumarate, and benzoate, but
did not grow autotrophically with H2, CO2, and sulfate. The closest relative of strain ASRB-Zg isDesulfotomaculum acetoxidans. The nitrate-reducing bacterium (strain ANRB-Zg) was rod-shaped (0.5–0.7 μm × 0.7–1 μm long), weakly motile, and gram negative.
Optimum growth with acetate occurred at 20–25°C. The bacterium grew on a range of organic substrates, such as acetate, butyrate,
lactate, and glucose, and did grow autotrophically with H2, CO2, and oxygen but not with nitrate. In the presence of acetate and nitrate, thiosulfate was oxidized to sulfate. Phylogenetically,
the closest relative of strain ANRB-Zg isVariovorax paradoxus. 相似文献
5.
The effects of temperature on photosynthesis of a rosette plant growing at ground level, Acaena cylindrostachya R. et P., and an herb that grows 20–50 cm above ground level, Senecio formosus H.B.K., were studied along an altitudinal gradient in the Venezuelan Andes. These species were chosen in order to determine
– in the field and in the laboratory – how differences in leaf temperature, determined by plant form and microenvironmental
conditions, affect their photosynthetic capacity. CO2 assimilation rates (A) for both species decreased with increasing altitude. For Acaena leaves at 2900 m, A reached maximum values above 9 μmol m−2 s−1, nearly twice as high as maximum A found at 3550 m (5.2) or at 4200 m (3.9). For Senecio leaves, maximum rates of CO2 uptake were 7.5, 5.8 and 3.6 μmol m−2 s−1 for plants at 2900, 3550 and 4200 m, respectively. Net photosynthesis-leaf temperature relations showed differences in optimum
temperature for photosynthesis (A
o.t.) for both species along the altitudinal gradient. Acaena showed similar A
o.t. for the two lower altitudes, with 19.1°C at 2900 m and 19.6°C at 3550 m, while it increased to 21.7°C at 4200 m. Maximum
A for this species at each altitude was similar, between 5.5 and 6.0 μmol m−2 s−1. For the taller Senecio, A
o.t. was more closely related to air temperatures and decreased from 21.7°C at 2900 m, to 19.7°C at 3550 m and 15.5°C at 4200 m.
In this species, maximum A was lower with increasing altitude (from 6.0 at 2900 m to 3.5 μmol m−2 s−1 at 4200 m). High temperature compensation points for Acaena were similar at the three altitudes, c. 35°C, but varied in Senecio from 37°C at 2900 m, to 39°C at 3550 m and 28°C at 4200 m. Our results show how photosynthetic characteristics change along
the altitudinal gradient for two morphologically contrasting species influenced by soil or air temperatures.
Received: 5 July 1997 / Accepted: 25 October 1997 相似文献
6.
Echinorhynchus hexagrammi Baeva, 1965 is redescribed on the basis of specimens collected from the saffron cod Eleginus gracilis (Tilesius) in Akkeshi Bay (western North Pacific) off Hokkaido, Japan. Eighteen museum specimens deposited as E. salmonis Müller, 1784 from Japanese coastal waters were also re-examined and re-identified as E. hexagrammi. Hexagrammos stelleri Tilesius, Hemitripterus villosus (Pallas), Podothecus sachi (Jordan & Snyder), Sebastes oblongus Günther and Verasper moseri Jordan & Gilbert are recognised as new hosts for E. hexagrammi. This acanthocephalan can be distinguished from three morphologically similar species, E. gadi Zoega in Müller, 1776, E. laurentianus Ronald, 1957 and E. salmonis, by the possession of the following characters: 12–16 (usually 14) rows of hook on the proboscis, a proboscis width of 170–240 μm
in males and 195–270 μm in females, a hook root length of 35–45 μm in males and 40–50 μm in females, and linearly or almost
linearly arranged cement glands in males. 相似文献
7.
E. E. Ezhova 《Russian Journal of Developmental Biology》2011,42(3):160-167
For the first time, under laboratory conditions, development of the polychaete Namanereis littoralis (Grube, 1876) is investigated. Under conditions of the Sea of Japan, its reproduction occurs in July and is confined to the
season of monsoon rains. Fertilization is external. Spawning manifests no epitocous transformations. Fecundity is low, ovicells
are rich in yolk, and development is nonpelagic, lecithotrophic, embryonized, characterized by a high rate—5–8 days—and occurs
in mucous clutches up to hatching of benthic juveniles. Temperature and salinity optima of development are 22–27°C and 16–21‰,
respectively, characterizing the species as subtropical brackish-water by its origin. Archaic and specialized traits are noted
in the early ontogenesis of N. littoralis. 相似文献
8.
Two proteolytic thermophilic aerobic bacterial strains, PA-9 and PA-5, were isolated from Buranga hot springs in western Uganda.
The cells were rods, approximately 10–12 μm in length and 3 μm in width. Isolate PA-9 grew at between 38°C and 68°C (optimum,
62°C), and PA-5 grew at between 37°C and 72°C (optimum, 60°C). Both isolates grew optimally at pH 7.5–8.5. Their 16S rRNA
gene sequences indicated that they belong to the newly described genus Geobacillus. Zymogram analysis of the crude enzyme extracts revealed the presence of two extracellular proteases for isolate PA-5, and
at least eight for isolate PA-9. The optimum temperature and pH for casein-degrading activity were 70°C, pH 6.5 for isolate
PA-9, but caseinolytic activity could also be observed at 2°C. In the case of isolate PA-5, optimal activity was observed
over a temperature and pH range of 50–70°C and pH 5–10, respectively.
Received: 26 November 2001 / Accepted: 12 December 2001 相似文献
9.
Background
Intercostal muscles are richly innervated by mechanoreceptors. In vivo studies of cat intercostal muscle have shown that there are 3 populations of intercostal muscle mechanoreceptors: primary muscle spindles (1°), secondary muscle spindles (2°) and Golgi tendon organs (GTO). The purpose of this study was to determine the mechanical transduction properties of intercostal muscle mechanoreceptors in response to controlled length and velocity displacements of the intercostal space. Mechanoreceptors, recorded from dorsal root fibers, were localized within an isolated intercostal muscle space (ICS). Changes in ICS displacement and the velocity of ICS displacement were independently controlled with an electromagnetic motor. ICS velocity (0.5 – 100 μm/msec to a displacement of 2,000 μm) and displacement (50–2,000 μm at a constant velocity of 10 μm/msec) parameters encompassed the full range of rib motion. 相似文献10.
Crowding effect in natural populations of three species ofSargassum, subtidal marine macrophytic algae, was investigated by harvesting all plants within a 1×1 m or 0.5×0.5m quadrat located
at depths of 3–5m in Tanabe Bay (33°41′N and 135°20′E).Sargassum populations conformed to the same 3/2 power law that holds in many terrestrial plant populations. 相似文献
11.
The predatory mite Typhlodromus bagdasarjani Wainstein and Arutunjan (Acari: Phytoseiidae) is an indigenous and widespread species of the Middle East fauna. In this paper
we assess the effect of temperature on developmental rate and reproduction potential of T. bagdasarjani under laboratory conditions. The development of this species was determined at 15, 20, 25, 30, 35 and 37.5 ± 1°C, 60 ± 10%
RH and L16:D8 h photoperiod. The total developmental time averaged 28.2, 15.0, 8.9, 7.6, 7.2 and 7.4 days at 15–37.5°C, respectively,
when feeding on immature stages of two-spotted spider mite, Tetranychus urticae Koch. The lower developmental threshold (T
0
) and thermal constant (K) for the development of this predator were estimated 9.2°C and 162 degree-days by the Ikemoto linear model. The life table
parameters were estimated at 15–35°C. The shortest life span of females at 35°C was 45.0 days, followed by 50.7, 50.9, 103.3
and 136.8 days at 30, 25, 20 and 15°C, respectively. Mated females laid on average 19.9, 26.3, 41.1, 39.6 and 31.3 eggs per
female at 15–35°C, respectively. The intrinsic rate of increase (r
m
) and finite rate of increase (λ) increased significantly with increasing temperature. The r
m
values ranged from 0.021 (15°C) to 0.186 (35°C) days−1. The highest value of net reproductive rate (R
0) was 13.6 females progeny/female/generation at 25°C. The results demonstrated that T. bagdasarjani is well adapted to high temperatures. However, the efficiency to control spider mites may be affected by behavioral characteristics
of the predator and its prey under real conditions. 相似文献
12.
Elżbieta E. Kopczyńska Nicolas Savoye Frank Dehairs Damien Cardinal Marc Elskens 《Polar Biology》2007,31(1):77-88
Variations of phytoplankton assemblages were studied in November–December 2001, in surface waters of the Southern Ocean along
a transect between the Sub-Antarctic Zone (SAZ) and the Seasonal Ice Zone (SIZ; 46.9°–64.9°S; 142°–143°E; CLIVAR-SR3 cruise).
Two regions had characteristic but different phytoplankton assemblages. Nanoflagellates(<20 μm) and pico-plankton (∼2 μm)
occurred in similar concentrations along the transect, but were dominant in the SAZ, Sub-Antarctic Front (SAF), Polar Front
Zone (PFZ) and the Inter-Polar Front Zone (IPFZ), (46.9°–56.9°S). Along the entire transect their average cell numbers in
the upper 70 m of water column, varied from 3 × 105 to 1.1 × 106 cells l−1. Larger cells (>20 μm), diatoms and dinoflagellates, were more abundant in the Antarctic Zone-South (AZ-S) and the SIZ, (60.9°–64.9°S).
In AZ-S and SIZ diatoms ranged between 2.7 × 105 and 1.2 × 106 cells l−1, dinoflagellates from 3.1 × 104 to 1.02 × 105 cells l−1. A diatom bloom was in progress in the AZ-S showing a peak of 1.8 × 106 cells l−1. Diatoms were dominated by Pseudo-nitzschia spp., Fragilariopsis spp., and Chaetoceros spp. Pseudo-nitzschia spp. outnumbered other diatoms in the AZ-S. Fragilaropsis spp. were most numerous in the SIZ. Dinoflagellates contained autotrophs (e.g. Prorocentrum) and heterotrophs (Gyrodinium/Gymnodinium, Protoperidinium). Diatoms and dinoflagellates contributed most to the cellular carbon: 11–25 and 17–124 μg C l−1, respectively. Small cells dominated in the northern region characterized by the lowest N-uptake and new production of the
transect. Larger diatom cells were prevalent in the southern area with higher values of N-uptake and new production. Diatom
and nanoflagellate cellular carbon contents were highly correlated with one another, with primary production, and productivity
related parameters. They contributed up to 75% to the total autotrophic C biomass. Diatom carbon content was significantly
correlated to nitrate uptake and particle export, but not to ammonium uptake, while flagellate carbon was well correlated
to ammonium uptake, but not to export. Diatoms have contributed highly to particle export along the latitudinal transect,
while flagellates played a minor role in the export. 相似文献
13.
Solveig K. Petursdottir Jakob K. Kristjansson 《Extremophiles : life under extreme conditions》1997,1(2):94-99
Mesophilic, moderately halophilic bacteria were isolated from a silica-rich geothermal lake, the Blue Lagoon in Iceland.
The isolates are strictly aerobic, but reduce nitrate to nitrite, and are oxidase- and catalase-positive. The nonsporeforming
and nonmotile Gram negative rods are 0.6–0.8 μm in diameter and variable in length (9–18 μm), and contain gas vacuoles. The
GC content in their DNA is 66.15%. The minimum, optimum, and maximum temperatures for growth are 22°C, 45°:C, and 50°C, respectively.
The isolates do not grow without added salt in the medium and can grow at up to 7% NaCl (w/v). The optimal salinity for growth
is 3.5%–4% NaCl. The pH range for growth is 6.5–8.5, with the optimal pH at 7.0. At optimal conditions the bacterium has a
doubling time of 80 min. The main cytochrome is a membrane-bound cytochrome c with an α-peak at 549 nm. Sequencing of 16S rRNA from the type strain ITI-1157 revealed it to be a proteobacterium of the
α-subclass with the closest relatives being Roseobacter litoralis and Paracoccus kocurii. The new isolates do not contain bacteriochlorophyll a and are considered to represent a new genus and a new species, Silicibacter lacuscaerulensis.
Received: September 17, 1996 / Accepted: December 10, 1996 相似文献
14.
The composition of the phytoplanktonic communities in the surface waters of the La Reunion-Kerguelen transect (from 38°36S
to 46°33S) has been investigated under spring conditions (Antarès 3 cruise, France-JGOFS, 28 September–8 November, 1995).
The study, conducted at six stations in the subtropical frontal zone, involved size fractionations (threshold: 2 μm). The
large variations in the overall biomass and autotrophic carbon fixation, calculated via Rubisco activity measurements and
expressed respectively in terms of μg chlorophyll (a + b + c) per liter and nmol fixed carbon dioxide per liter and per hour, were attributable only to phytoplanktonic cells of >2 μm,
with a peak observed in the frontal zone. The picophytoplankton (<2 μm) biomass remained constant throughout the transect,
but the evolution of the species composition of the picophytoplanktonic population, as calculated from flow cytometry measurements
through this frontal zone, changed. This study provides evidence, for the first time in this area, of the disappearance of
prochlorophytes from the south of the frontal zone (42–47°S). Picoeukaryotes (<2 μm) and cyanobacteria populations, resolved
by flow cytometry, were present all along the transect. However, their abundance decreased southward up to the quasi-disappearance
of cyanobacteria at the southernmost station (52°S) that is characteristic of antarctic waters. The presence of prochlorophytes
that is exclusive to the subtropical surface waters, and the low carbon fixation activity associated with these waters, may
be linked to the specific hydrological features encountered. In contrast, the marked reduction in the cyanobacteria and the
abundance of picoeukaryotes along the north-south transect is more likely to be a result of the reduction in temperature through
the frontal zone.
Accepted: 17 July 1998 相似文献
15.
Dynamics of Mya arenaria beds in two bights of the Chupa Inlet (Kandalaksha Bay, White Sea) were studied on a long-term basis. Observations were carried
out at 1– to 3-year intervals from 1979 up to 1999. The studied soft-shell clam beds were characterised by a substantial instability
of age structure. Since 1988, only one year-class has dominated in the beds while other generations have been scarce and recruitment
was not observed. This pattern of Mya bed dynamics was related neither to interannual environmental changes nor to differential reproduction success or predation
effects in the benthic assemblages. Favourable conditions for spat formation in 1988 (low abundance of other M. arenaria generations), as well as for juvenile survival during the following winter, resulted in high abundance of juveniles in both
investigated locations in 1989. The mortality rate (μ) in this 1988 generation varied throughout the period of investigation and was related to age. The mortality level decreased
for the first 2–4 years of the life cycle, then stabilised for the next 3–4 years, and eventually increased in subsequent
years. Overall μ values ranged from 0 to 1.68 year–1. The oldest specimens observed were 17 years old and had a maximum shell length of 79 mm. Significant differences in average
growth rates were observed between molluscs of different locations.
Communicated by H.-D. Franke 相似文献
16.
The relationship between the particle size of an inert silica dust, its up-take from different surfaces and the grooming behaviour
of males, gravid females, and fifth and sixth instar nymphs of the German cockroachBlattella germanica (Dictyoptera: Blattellidae) (L.) was investigated. The normal grooming behaviour of gravid females, nymphs and males differed
according to sex and age. The gravid females and nymphs exhibited greater grooming activity than the males, especially of
the antennae and the legs. Gravid females, nymphs, and adult males exhibited increased grooming activity after exposure to
dust in the size range 0.5–63 μm, but there was no significant difference in grooming behaviour from the control when cockroaches
were exposed to dust sizes greater than 70 μm. Antennal grooming by males was greater than leg grooming when exposed to all
dust sizes, except size particles ranging 4.5–7.5 μm. A dust pick-up experiment indicated that the average amount of dust
transferred toB. germanica is affected by particle size, the porosity of the treated surface, and the sex and age of the cockroaches. Gravid females
picked up greater amounts of dust than fifth and sixth instar nymphs, which in turn picked up more dust than males. Silica
dust particles (0.5–7.5 μm) were picked up more effectively than larger particle sizes, by all three categories, males, females
and fifth and sixth instar nymphs of cockroach on all three test surfaces plastic, ceramic and unpainted plywood. Plywood
was the least effective surface for transfer of dust, of all sizes, to males, females and nymphs. 相似文献
17.
P. Rodriguez J. Arrate M. Martinez-Madrid T. B. Reynoldson V. Schumacher J. Viguri 《Hydrobiologia》2006,564(1):157-169
The freshwater euryhaline oligochaete Limnodrilus hoffmeisteri was selected for use in bioassays with polluted sediment from Santander Bay. It is easy to culture; is tolerant of low to
moderate, up to 15‰, salinity; and is common in oligohaline conditions in European and North American estuaries. Worms were
collected from an estuarine population and kept in unpolluted sediment for between 2 and 4 weeks, under laboratory conditions,
at 7–8.5‰ salinity and 22.5 °C. Sediment from different sites in Santander Bay were sieved through 250 μm mesh and adjusted
to a salinity of approx. 7‰ prior to the bioassays, either by adding sea water or dechlorinated tap water to the overlying
water. High levels of ammonia in some sediment, which may confound results in ecotoxicity bioassays, were reduced by oxidation
of the sediments in shallow trays. Sediment bioassays were performed with sexually mature Limnodrilus hoffmeisteri worms in 250-ml beakers, with a 1:3 ratio of sediment:water and 4 worms per baker. Endpoints in the 14-day bioassay were
% mortality, adult final biomass, % adults that have shown resorption of the clitellum, number of cocoons, and burrowing behaviour.
It was possible to rank the sites according to their toxicity using both mortality rates and sublethal effects. The control
site had the following values for the endpoints: 5% mortality, (
) 2.40 ± 1.52 cocoons per beaker and 1.271 ± 0.470 mg dw adult final biomass. The most toxic sediment resulted in 65% mortality,
resorption of the clitellum in 67% of the adults, no production of cocoons and a low final biomass (
=0.681 ± 0.489 mg dw per adult). A second site had high mortality (60%) and no reproduction, although resorption of the clitellum
did not occur in surviving animals. The remaining sites showed similar mortality (35–42%), and at only one of them was low
reproduction observed (0.8 ± 0.447 cocoons per beaker). Behavioural effects, measured as length of galleries in a fixed area
of the test-vessel at the end of the bioassay, were significant compared with control at only one site. Multivariate analysis
showed the mortality gradient to be the strongest, with a second unassociated gradient representing clitellum resorption.
The mortality gradient was associated with Cu and Zn concentration, and PAH and Pb possibly with resorption. 相似文献
18.
Quadrastichus citrella Reina and La Salle (Hymenoptera: Eulophidae) is a parasitoid of Phyllocnistis citrella Stainton (Lepidoptera: Gracillariidae), indigenous to South Eastern Asia where it is considered a key natural enemy of this pest. It was introduced in Spain in a classical biological control program and became established, but was not as successful as forecast. To check whether its biology could explain this lack of control, development and reproduction at different temperatures were studied. Quadrastichus citrella can survive at temperatures between 15 and 35 °C. Lower development threshold was 12.3 °C, which resulted in a thermal constant of 138.06 DD. The combination of development and reproduction into demographic parameters resulted in highest net reproduction occurring in the range 20–25 °C (78.2 females per female), and highest intrinsic rate of increase at 30 °C (0.2571 females per female per day). These values make Q. citrella an intrinsically superior natural enemy compared to other leaf miner parasitoids. However, overwintering of Q. citrella in Spain may present a barrier, especially in areas like Valencia, where average winter temperatures are around 11 °C. This could account for the low recovery rates observed in Spain in spite of the key natural enemy status enjoyed by this species in its area of origin. 相似文献
19.
Two 60-day experiments were conducted to study the influence of photon flux density (PFD) and temperature on the attachment
and development of Gloiopeltis tenax and Gloiopeltis furcata tetraspores. In the first experiment, tetraspores of the two Gloiopeltis species were incubated at five temperature ranges (8°C, 12°C, 16°C, 20°C, 24°C) under a constant PFD of 80 μmol photons m−2 s−1 with a photoperiod of 12:12. In a second experiment, tetraspores were incubated under five PFD gradients (30, 55, 80, 105,
130 μmol photons m−2 s−1) at a constant temperature of 16°C with a photoperiod of 12:12. Maximum density of attached tetraspores was observed at 16°C
for both species. Maximum per cent of spore germinating into disc was recorded at 12–16°C for G. tenax and 8–12°C for G. furcata. Maximum per cent of discs producing erect axes for G. tenax and G. furcata were recorded at 24°C and 20°C, respectively. Light had no significant effect on tetraspore attachment and developing into
disc, but it affected the growth, sprouting and survival of its discs. Under 30–55 μmol photons m−2 s−1, the discs of the two species of Gloiopeltis did not form thallus until the end of the experiment. Optimum PFD range for G. tenax discs was 80–105 μmol photons m−2 s−1, whilst it was 80–130 μmol photons m−2 s−1 for G. furcata. Results presented in this study are expected to assist the progress of artificial seeding of Gloiopeltis. 相似文献
20.
G. Zimmermann 《BioControl》1978,23(2):181-187
Zusammenfassung Von pilzbefallenen Larven der KohlschabePlutella maculipennis
Curt. wurdeEntomophthora blunckii
Lakon exZimmermann isoliert. Die Art wird mit lateinischer Diagnose gültig beschrieben, die morphologischen Merkmale werden erg?nzend angegeben
und erstmals durch Fotos belegt.E. blunckii w?chst gut auf koaguliertem Eidotter, weniger gut auf Sabouraud-Glucose-Agar. Mycelwachstum wurde zwischen 8° und 28°C beobachtet,
dagegen nicht bei 32°C. Die Symptome infizierter Larven werden geschildert und der Pilz wird mit ?hnlichen Arten verglichen.
Summary Entomophthora blunckii Lakon exZimmermann was isolated from larvae of the diamondback-mothPlutella maculipennis Curt. and redescribed. The fungus is characterized by its elliptical to pear-shaped conidia (from infected larvae 13–20×7–11 μm, mostly 15–18×7–9 μm) with the outer membrane often inflated and its branched conidiophores forming a dense gray to faint greenish-yellowish covering over the body of the insect. The symptoms of larvae infected withE. blunckii are described. The species grows on coagulated egg yolk, less well on Sabouraud-Dextrose-Agar. Growth was observed between 8° and 28°C but not at 32°C. The fungus is compared with similar species.相似文献