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1.
P. J. Nico de Bruyn Pierre A. Pistorius Cheryl A. Tosh Marthán N. Bester 《Polar Biology》2007,30(10):1355-1358
A leucistic immature male Antarctic fur seal, Arctocephalus gazella, was sighted at Marion Island in April 2006; the first such sighting in three decades of extensive field presence of biologists
at this locality. The same animal returned to the island in July/August 2006, when it was moulting, and was marked with unique
flipper tags, after which it was sighted in early October 2006 again. Considering that individuals of this species are capable
of moving far from their natal population, we suggest that the animal could likely have come from South Georgia, where this
colour morph is relatively common. 相似文献
2.
We document five cases of unusual colouration in Antarctic fur seals, Arctocephalus gazella, at Cape Shirreff, Livingston Island, from 1991–1992 to 2005–2006 austral summer seasons. This is the first time that these
colour patterns have been reported for this species. These included four rare light coloured animals and one piebald individual.
The incidence of this atypical colouring was low and the lack of resightings in previous and subsequent seasons suggests that
these morphs are not common in Antarctic fur seals. Although the causes of these atypical light colour patterns are uncertain
the subject is interesting for study and more observations on these atypical colourations are required for a proper assessment
of the ecological and physiological implications of this condition in otariids can be conducted in the future. 相似文献
3.
A. B. Makhado M. N. Bester S. P. Kirkman P. A. Pistorius J. W. H. Ferguson N. T. W. Klages 《Polar Biology》2008,31(5):575-581
The prey of Antarctic fur seals, Arctocephalus gazella, was investigated through scat analysis at Marion Island from 1996 until 2000. A total of 25 different prey species were
identified from scats, of which 21 were fish, 1 crustacean and 3 cephalopods. Fish were by far the main prey item, occurring
in 96.1% of samples, followed by crustaceans (2.7%) and cephalopods (1.2%). Fishes from the family Myctophidae (Gymnoscopelus piabilis, Electrona carlsbergi, G. fraseri and E. subaspera) were the most abundant prey (97.2%) every year, while those from the families Notothenididae, Paralepididae, Notosudidae,
Microstomatidae and Gempylidae were present in small numbers. G. piabilis, E. carlsbergi, E. subaspera and G. nicholsi contributed the most in terms of biomass to the diet. Significant seasonal differences existed in the diet when comparing
summer and winter. G. piabilis, K. anderssoni, P. bolini and P. choriodon dominated in summer as opposed to E. carlsbergi, E. subaspera, G. fraseri and G. nicholsi that dominated in winter. The fish varied in size and mass, from the small K. anderssoni to the large Paranotothenia magellanica. Cephalopods and the crustacean Nauticaris marionis, in very low numbers and in winter, appeared in the scats, but not in all years of study. Unidentified penguin remains rarely
turned up in scats. 相似文献
4.
G. A. Daneri A. R. Carlini A. Harrington L. Balboni C. M. Hernandez 《Polar Biology》2008,31(11):1365-1372
The diet of non-breeding male Antarctic fur seals, Arctocephalus gazella, was investigated at Stranger Point, King George Island, through the analysis of scats during three consecutive summer seasons
(1996, 1997, 1998). Overall, fish and krill were the most frequent prey occurring, respectively, in an average of 82.9% and
78.8% of samples (n = 131), followed by penguins (22.8%) and cephalopods (17.8%). Myctophids constituted almost 90% of the fish predated, with
Electrona antarctica and Gymnoscopelus nicholsi being the most abundant and frequent species consumed. All fish taxa identified were krill feeding species suggesting that
seals foraged mainly on a krill and a fish community associated with krill aggregations. However, a seasonal change was observed
in the relative proportions of the different prey taxa, with a progressive decrease with time in the occurrence of krill and
a concomitant increase of fish, penguins and squid. Possible influence of the strong 1997/98 ENSO event is discussed. 相似文献
5.
Jorge Hernandez Valeria Prado Daniel Torres Jonas Waldenström Paul D. Haemig Björn Olsen 《Polar Biology》2007,30(10):1227-1229
Rectal swabs were collected from Antarctic fur seal pups Arctocephalus gazella at Cape Shirreff, South Shetland Islands, and analyzed for the presence of anthropogenic pathogens. Two of the 33 pups tested
positive for enteropathogenic Escherichia coli (EPEC). These samples are the first records of EPEC in Antarctic wildlife and suggest that more needs to be done to protect
the Antarctic fauna from exotic anthropogenic pathogens. 相似文献
6.
7.
L. Y. Solís-Ramos T. González-Estrada S. Nahuath-Dzib L. C. Zapata-Rodriguez E. Castaño 《Plant Cell, Tissue and Organ Culture》2009,96(3):279-287
Capsicum chinense is a recalcitrant species for in vitro morphogenesis, and up to date there is no efficient system for genetic transformation
and regeneration of this species via somatic embryogenesis. Here, we carried out an in vitro transformation of C. chinense via Agrobacterium tumefaciens co-cultivation with a system that expresses the heterologous gene WUSCHEL from Arabidopsis thaliana. WUSCHEL has been shown to promote the transition from vegetative to embryogenic state when overexpressed. We tested if the expression
of WUSCHEL in C. chinense would promote an embryogenic response in this species. After 15 days of induction, the segments of transformed stems begun
to form globular structures, suggesting that heterologus WUSCHEL was active and involved in the process of morphogenesis. 相似文献
8.
Gaye Öngen Gaye Güngör Bahar Kanberoglu 《World journal of microbiology & biotechnology》2007,23(4):519-524
Aspergillus section Nigri strains Aspergillus aculeatus Ege-K 258, A.
foeditus var. pallidus Ege-K156, A. niger Ege-K 4 and A. tubingensis Ege-K 265 were used to treat olive mill wastewater (OMW) in an investigation aimed at exploring their dephenolisation and
decolourisation ability and, consequently, the economic feasibility of using any or all of these strains in a pre-treatment
step in the processing of OMW. Of these strains A. tubingensis Ege-K 265 resulted in an 80% decolourisation of twofold-diluted OMW and a 30% decolourisation of undiluted OMW; in addition,
it was able to remove approximately 30% of all phenolic compounds in both twofold-diluted and undiluted OMW. We conclude that
A. tubingensis Ege-K 265 could be effectively used in the pre-treatment step of a combined aerobic-anaerobic process to solve the environmental
problems caused by OMW in Mediterranean countries. 相似文献
9.
10.
S. E. Dawson 《Kew Bulletin》2008,63(3):517-517
Summary The name Pavetta modesta (Hiern) S. E. Dawson is a later homonym of P. modesta Bremek. Pavetta crystalensis is proposed as a new name. 相似文献
11.
12.
Dmitar Lakušić 《Biologia》2008,63(5):631-636
The south-European Cardamine plumieri Vill. (sect. Pteroneurum subsect. Cryptopterum) is confirmed for the Flora of Serbia. Several populations were discovered in the central and western part of country, exclusively
on the serpentine bedrocks. Morphological, chorological and ecological characteristics of C. plumieri was studied. 相似文献
13.
A. Q. Hurtado A. T. Critchley A. Trespoey G. Bleicher-Lhonneur 《Journal of applied phycology》2008,20(5):551-555
Kappaphycus striatum var. sacol was grown in two separate studies: (1) at two stocking densities, and (2) at four different depths, each for three different
durations of culture (30, 45 and 60 days) in order to determine the growth rate of the seaweed and evaluate the carrageenan
content and its molecular weight. The results demonstrated that stocking density, duration of culture and depth significantly
(P < 0.01) affected the growth rate, carrageenan content and molecular weight of K. striatum var. sacol. Decreasing growth rate was observed at both stocking densities and at four depths as duration of culture increased. A lower
stocking density (500 g m−1line−1) showed a higher growth rate for the shortest durations, i.e. 30 days, as compared to those grown at a higher density. Likewise,
decreasing growth rate was observed as depth increased, except at 50 cm after 60 days of culture. A 45-day culture period
produced the highest molecular weight at both stocking densities (500 g m−1line−1 = 1,079.5 ± 31.8 kDa, 1,000 g m−1line−1 = 1,167 ± 270.6 kDa). ‘Sacol’ grown for 30 days at 50 cm (1,178 kDa) to 100 cm (1,200 kDa) depth showed the highest values
of molecular weight of carrageenan extracted. The results suggested that K. striatum var. sacol is best grown at a stocking density of 500 g m−1line−1, at a depth of 50–100 cm, and for a duration of 30 days in order to provide the highest growth rate, carrageenan content
and molecular weight. 相似文献
14.
Peter G. Wilson 《Kew Bulletin》2008,63(2):347-349
Summary The type specimen of Metrosideros regelii is discussed. It contains a mixture of two species, representing different genera, and a lectotype is chosen. The generic
position of the species is considered in the light of morphology and recent molecular evidence and the new combination, Mearnsia regelii, made. 相似文献
15.
The architecture of the musculature of the eutardigrade species Milnesium tardigradum Doyère, 1840, Hypsibius sp. and Ramazzottius oberhaeuseri (Doyère in Ann Sci Nat Zool Sér 2(14):269–369, 1840) is investigated by phalloidin staining and confocal laser scanning microscopy. There are methodological problems in staining
eutardigrades due to physiological alterations under stress (anhydrobiosis) and due to penetration problems of the cuticle.
It is helpful to fix specimens in the state of asphyxy, where animals are stretched following an oxygen shortage in their
environment. The musculatures of all three species correspond in their general architecture, but differ in detail, such as
in the number of muscles. All muscles are isolated muscle strands. There are on each body side two dorsal and one ventral
muscle strands, in addition to a system of dorsoventral, lateral and lateroventral muscles. Seven median ventral attachment
points give rise to dorsoventral, ventrolateral and appendage muscles. The appendages receive several muscles originating
dorsally and ventrally. The number of muscles and the arrangement differ in each appendage. The fourth appendage shows the
greatest differences with a far smaller number of muscles compared to other species. The musculature shows comparably few
strict segmental patterns, for example, the musculature of each appendage differs from the other ones. By comparison with
literature data on the same species and data of Macrobiotus hufelandi it can be shown that eutardigrades have a roughly comparable muscular architecture, but that there are several differences
in detail.
Dedicated to Professor Westheide on the occasion of his 70th birthday. 相似文献
16.
The seasonal occurrence of Mycosphaerella buna in leaves and contiguous organs of Fagus crenata was studied in a Japanese beech forest, Ibaraki, Japan, in 1998 and 1999. Mycosphaerella buna was not isolated from newly developed leaves in May, but it was isolated from asymptomatic leaves after June. The frequency of its occurrence gradually increased until leaffall. In contrast, M. buna was not isolated from overwintered buds, leaf petioles, or contiguous current-year twigs. The spermogonia and pseudothecia were observed in dead leaves after leaffall. The mature pseudothecia were found on dead leaves from May to July. The ascospores produced in the pseudothecia were suggested to infect newly developed leaves.Contribution no. 173, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba, Japan 相似文献
17.
Septobasidium parviflorae sp. nov. on Pinus parviflora is described and illustrated. This species is characterized by its whitish-gray, gray to dark gray-colored fungus body with
an indeterminate margin, hyphal strands, and cylindrical basidia with long sterigmata. This is the first report of Septobasidium occurring on a member of the genus Pinus in Japan. 相似文献
18.
S. Kumar Sunil Kumar S. P. Negi J. K. Kanwar 《In vitro cellular & developmental biology. Plant》2008,44(6):474-479
Callus cultures derived from leaf segments of chrysanthemum cultivar ‘Snow Ball’ which was susceptible to Septoria obesa were successfully used for in vitro selection for resistance to this pathogenic fungus. Resistant cell lines were selected by culturing callus on growth medium
containing various concentrations of S. obesa filtrate. Resistant calluses obtained after two cycles (30 d each cycle) of selection were used for plant regeneration. About
30% of the plants regenerated from the resistant calluses and 70–80% of the plants raised from cuttings had acquired considerable
resistance against the pathogen in the field. No phenotypic variation was observed in the selected regenerates. 相似文献
19.
A. L. Allcock J. M. Strugnell P. Prodöhl U. Piatkowski M. Vecchione 《Polar Biology》2007,30(7):883-893
During recent cruises aboard RV Polarstern in the Antarctic Peninsula region, a new species of benthic octopodid was discovered whose generic affinities based on morphological
characteristics were uncertain. Molecular sequence analysis of six mitochondrial and nuclear genes allows this species to
be placed with confidence within the genus Pareledone. The species is described herein and morphological diagnostic characters are provided for its identification. 相似文献