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1.
Citrus is an important fruit crop as regards accumulation of carotenoids. In plant carotenoid biosynthesis, phytoene synthase gene
(Psy) plays a key role in catalyzing the head-to-head condensation of geranylgeranyl diphosphate molecules to produce colorless
phytoene. In the present paper, we reported the phytoene contents determination and characterization of Psy during fruit ripening of “Washington” navel orange and its red-fleshed mutant “Cara Cara”. Results showed that phytoene was
exclusively accumulated in peel and pulp of “Cara Cara”. Although phytoene was observed accumulating with fruit ripening of
“Cara Cara”, the contents in pulp were 10 times higher than those in peel. The isolated two Psy cDNAs were both 1520 bp in full length, containing 436 deduced amino acid residues, with a different amino acid at 412th.
Genomic hybridization results showed that one or two copies might be present in “Cara Cara” and “Washington” genomes. During
“Cara Cara” and “Washington” fruit coloration, expression of Psy was observed to be up-regulated, as revealed by tissue specific profiles in the flavedo, albedo, segment membrane and juice
sacs. However, Psy expression in albedo of “Cara Cara” was higher than that in “Washington”, as evidenced by phytoene accumulation in the peel. 相似文献
2.
The Macrotermitinae are a large and successful subfamily of fungus-growing termites, characterised by their symbiotic association
with white-rot fungi of the genus Termitomyces. The taxonomy of the subfamily, and in particular of the largest genus Odontotermes, is problematic. We used sequences of the mitochondrial 16S gene from termites occurring in East Africa and Malawi to explore
the phyletic relationships within the genus Odontotermes and to place the genus in the broader context of other fungus-growing termites. We also interpret this phylogeny in relation
to classical morphological taxonomy in the form of absolute and relative dry weights of the sterile castes, and in relation
to innate behaviour as shown by nest architecture and fungus comb structure. This work lays the foundations of a complete
taxonomic revision of the Macrotermitinae.
The phylogeny supports one clear subdivision, here called the “tanganicus” group, within the genus Odontotermes. It also supports the significance of field observations on the structure of fungus combs, as the whole “tanganicus” group
builds fungus combs of the sponge type (or modified forms thereof) which are hardly known elsewhere. Other phyletic relationships
are less clear, the residual sequences being referred to as the “latericius” group. We recognise three probable miniature
species within the “tanganicus” group and another possible one in the residual “latericius group”.
Received 16 January 2007; revised 30 October 2007 and 11 March 2008; accepted 4 April 2008. 相似文献
3.
New species of Pogonophryne (Pisces, Artedidraconidae) from the Bellingshausen Sea, Antarctica 总被引:1,自引:1,他引:0
A new species of notothenioid fish, Pogonophryne bellingshausenensis n. sp., is described from the Bellingshausen Sea, Antarctica. The new species belongs to the dorsally-spotted “mentella”
group of the genus and is characterized by having a short (about 13% SL) mental barbel with a short (about 16% of barbel length),
narrow (barely wider than the stalk), and relatively inconspicuous terminal expansion composed of short, irregular, fingerlike
processes. Compared to most other dorsally-spotted species of Pogonophryne (“barsukovi”, “marmorata”, and “mentella” groups), P. bellingshausenensis has a relatively wide (about 7% SL) interorbital region. An unspotted patch on the median dorsal surface of the head, posterior
to the posttemporal ridges and anterior to the first dorsal fin, has not been observed previously in any dorsally-spotted
species. The holotype was collected at 1,947 m, one of the deepest records for any species of Pogonophryne. A revised key to the ten species of the “mentella” group of Pogonophryne is also provided. 相似文献
4.
Chiara Angelone 《Pal?ontologische Zeitschrift》2009,83(1):67-75
Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern
Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different
species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental
Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude
any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of
European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.
相似文献
5.
Showe-Mei Lin 《Journal of applied phycology》2006,18(3-5):671-678
Four flattened Gracilaria species have been reported from Taiwan: G. spinulosa, G. vieillardii, G. textorii and G. punctata, identified based on branching pattern, the presence or absence of spines, and characters that often vary seasonally. Gracilaria spinulosa was originally described from the type locality, Tainan. Species with toothed margins are usually referred to G. “vieillardii”; those with smooth margins to G. “textorii”, and those with smooth margins and dark spots scattered over the blade to G. “punctata”. Molecular analyses show that specimens with marginal teeth cluster in three different groups: a G. “vieillardii” clade, a G. spinulosa clade, and a clade sister to G. spinulosa. An undescribed species comprises the third clade, which is distinguished by its relatively large gonimoblast cells and weakly developed tubular nutritive cells. The three clades can be separated by the character of the tubular nutritive cells, the size of gonimoblast cells and certain vegetative features. Plants with entire margins form a single clade characterized by cystocarps with basal tubular nutritive cells and their absence in the cystocarp cavity. They are nested in the Hydropuntia complex and are referred to as Gracilaria “punctata” here. The records of G. textorii and G. punctata from Taiwan require reinvestigation in comparison with the Japanese species. 相似文献
6.
George D. Koufos Louis de Bonis Dimitris S. Kostopoulos Laurent Viriot Theodora D. Vlachou 《Pal?ontologische Zeitschrift》2004,78(1):213-228
Two skulls, two mandibles and some postcranials ofMesopithecus from the locality “Vathylakkos 2” of Axios Valley (Macedonia, Greece) enlarge our knowledge about the genus and its differentiation.
The new material together with an old skull from the same locality is compared with the Pikermi, “Ravin des Zouaves 5” (Axios
Valley), and Maramena (Serres basin) samples. It is concluded that the VathylakkosMesopithecus resemblesM. pentelicus from Pikermi, as wellM. delsoni from “Ravin des Zouaves 5” and it is referred asMesopithecus sp. aff.M. pentelicus. The biochronological age of “Vathylakkos 2” has been considered as MN 12, while recent magnetostratigraphic data indicate
an age of about 7.5 Ma. This age confirms the position of the VathylakkosMesopithecus between Pikermi and “Ravin des Zouaves 5”. Some dental indices compared with those of the RecentCercopithecus suggest that the Vathylakkos sample is monospecific.
相似文献
7.
Hanna Ciecierska 《Hydrobiologia》2006,570(1):141-146
Urban lakes belong to various groups, for example from “young” to “old” with regard to development, and from “natural” to
“anthropogenic” with respect to transformations due to human activity. The majority of these lakes are eutrophic and polytrophic,
but special attention should be paid to mesotrophic ones, with relatively unchanged vegetation, with species of the class
Charetea, e.g. Lake Redykajny (43.3% of the phytolittoral) or Lake Tyrsko (44.0% of the phytolittoral). 相似文献
8.
A reevaluation of floral and vegetative morphology together with data from analysis of floral fragrance and flavonoid co-pigment
chemistry suggest that specific status is warranted for the two kinds ofPhalaenopsis violacea Witte known informally as the “Bornean type” and the “Malayan type.”Phalaenopsis violacea var.bellina Rchb.f. is elevated to specific rank, providing a name for the “Bornean type” plants. 相似文献
9.
Hiromitsu Endo Naohide Nakayama Kishiko Suetsugu Hiroshi Miyake 《Ichthyological Research》2010,57(3):272-277
A late-stage larva of Coryphaenoides pectoralis was first observed in situ and subsequently collected by the deep-sea submersible “Shinkai 2000” from mesopelagic waters at a depth of 530 m off Hokkaido, Japan. The larva (14.5 mm in head length, 149+ mm in total length)
has fan-like pectoral fins, elongate first dorsal fin, pelvic fin and tail, 10 first dorsal rays (including 2 pseudospines),
and 7 pelvic fin rays, 6 branchiostegal rays, no light organ, anus just anterior to anal fin origin, 2 retia and gas glands,
14 abdominal vertebrae, and previously reported larval pigmentation. Counts of second dorsal and anal fin rays, and caudal
vertebrae, are reported for the first time. 相似文献
10.
Anna-Mária Cserg? Szilárd Nemes Dan Gafta László Demeter Sámuel Jakab 《Plant Ecology》2009,203(2):229-242
We modelled the effect of habitat heterogeneity on the abundance of the submediterranean Saponaria bellidifolia, a red list species in Romania. The study was designed at two scales: 100 and 0.5 m2. At larger scale, generalized additive models and canonical correspondence analysis were used to model the density of ramets,
whereas at microscale, binomial logistic regression was employed to model the species’ occurrence. S. bellidifolia abundance responded sensitively to habitat type (classified as “grassy”, “rocky” and “scree”), rather than to microclimatic
variables. At both scales, habitat type was the best predictor of ramet abundance, followed by slope and vegetation cover.
At 0.5 m2, soil depth was also a good predictor of species occurrence. The data revealed that screes are the most suitable habitats
for hosting relatively large populations of this rare species, because of occasional natural disturbances and presumably lower
interspecific competition. 相似文献
11.
Liparidae from stomachs of Antarctic toothfish Dissostichus mawsoni Norman, 1937 (Nototheniidae) caught in the Ross Sea (Pacific sector of Antarctica) have been identified. Two new species
of deep-water liparids of the genus Paraliparis Collett, 1879—P. caninus sp. nov. (at a depth of 1182–1651 m) and P. vipera sp. nov. (1700 m)—were described. Both species that turned out to be most similar to P. neelovi Andriashev, 1982, from the Kerguelen area (the Indo-Oceanic sector of the South Ocean) are combined with it into a species
group “P. neelovi.” According to meristic characters, pattern of dentition, and the size of gill opening, species of “P. neelovi” are close to the species group “P. copei.” In collections from a depth of 1700 m, also two individuals of P. andriashevi Stein et Tompkins, 1989, known previously from only two types from the northern boundary of the Ross Sea were found. The
new finding supports species validity and extends the known limits of its range. The wide distribution of bathybenthal Paraliparis having low fecundity and leading a near-bottom mode of life can be explained by the presence of mesopelagic juveniles and
their dispersal via currents. 相似文献
12.
Summary The shallow marine subtropical Northern Bay of Safaga is composed of a complex pattern of sedimentary facies that are generally
rich in molluscs. Thirteen divertaken bulk-samples from various sites (reef slopes, sand between coral patches, muddy sand,
mud, sandy seagrass, muddy seagrass, mangrove channel) at water depths ranging from shallow subtidal to 40m were investigated
with regard to their mollusc fauna >1mm, which was separated into fragments and whole individuals.
Fragments make up more than 88% of the total mollusc remains of the samples, and their proportions correspond to characteristics
of the sedimentary facies. The whole individuals were differentiated into 622 taxa. The most common taxon,Rissoina cerithiiformis, represented more than 5% of the total mollusc content in the samples. The main part of the fauna consists of micromolluscs,
including both small adults and juveniles. Based on the results of cluster-, correspondence-, and factor analyses the fauna
was grouped into several associations, each characterizing a sedimentary facies: (1) “Rhinoclavis sordidula—Corbula erythraeensis-Pseudominolia nedyma association” characterizes mud. (2) “Microcirce sp.—Leptomyaria sp. association” characterizes muddy sand. (3)”Smaragdia spp.-Perrinia stellata—Anachis exilis—assemblage” characterizes sandy seagrass. (4) “Crenella striatissima—Rastafaria calypso—Cardiates-assemblage” characterizes muddy seagrass. (5) “Glycymeris spp.-Parvicardium sueziensis-Diala spp.-assemblage” characterizes sand between coral patches. (6) “Rissoina spp.-Triphoridae —Ostreoidea-assemblage” characterizes reef slopes. (7) “Potamides conicus—Siphonaria sp. 2—assemblage” characterizes the mangrove.
The seagrass fauna is related to those of sand between coral patches and reef slopes with respect to gastropod assemblages,
numbers of taxa and diversity indices, and to the muddy sand fauna on the basis of bivalve assemblages and feeding strategies
of bivalves. The mangrove assemblage is related to those of sand between coral patches and the reef slope with respect to
taxonomic composition and feeding strategies of bivalves, but has a strong relationship to those of the fine-grained sediments
when considering diversity indices. Reef slope assemblages are closely related to that of sand between coral patches in all
respects, except life habits of bivalves, which distincly separates the reef slope facies from all others. 相似文献
13.
This is the first report documenting the responses of wild chimpanzees (Pan troglodytes schweinfurthii) to seismic activities. During our long-term fieldwork in Mahale Mountains National Park, Tanzania, a high-intensity earthquake
with a Richter magnitude of 6.8 occurred at 15:19 hours local time on 5 December 2005. During the main tremor, the chimpanzees
displayed the “wraa” call, “scream,” and “pant bark” or “bark” vocalizations. Many mild aftershocks followed the main tremor,
and the wild chimpanzees displayed a variety of responses to these. In several cases, they climbed trees or stopped activities
such as grooming, moving, and feeding. These responses are similar to those previously reported in nonhuman primates. During
the observations, a unique behavior, one never reported before was exhibited by a female chimpanzee. She placed her right
palm on the ground giving the impression she was inspecting the trembling of the ground. 相似文献
14.
Masayoshi Maehata 《Ichthyological Research》2002,49(2):202-205
Mating behavior of the Far Eastern catfish, Silurus
asotus (Siluriformes: Siluridae), was observed in a ricefield system facing the shore of Lake Biwa in mid-May to early June in 1990–1997.
A set behavioral sequence similar to those of two other silurid fishes, S. biwaensis and S. lithophilus, both endemic to the Lake Biwa system, was observed: “chasing,”“clinging,”“enfolding” while “squeezing” by the male, and
“circling” by the spawning pair. This form of mating behavior is quite different from that of S. asotus reported from the Ooi River system in Kyoto Prefecture, which mainly spawns in running water in ditches.
Received: April 10, 2001 / Revised: November 5, 2001 / Accetped: November 20, 2001 相似文献
15.
The composition of the coastal fish fauna around Elephant Island (South Shetland Islands, Antarctica) 总被引:8,自引:8,他引:0
The composition of the coastal fish fauna around Elephant Island (northern South Shetland Islands) was investigated during
seven bottom trawl surveys of FRV “Walther Herwig”, FV “Polarstern” and FRV “Yuzhmorgeologiya” from 1981 to 1998. Low-Antarctic
(or lesser or peri-Antarctic) fish species were the predominant element of the coastal fish fauna. Large-scale fishing from
1978 to 1981 reduced stock sizes of the most abundant species Champsocephalus gunnari and Notothenia rossii to the extent that only a small fraction of the initial stock remained. After the period of intensive fishing, Gobionotothen gibberifrons became the most abundant species around the island. The by-catch species, which had probably been less affected by harvesting,
recovered by the end of the 1980s/beginning of the 1990s. Fish biomass was highest in the 100- to 400-m depth range. An MDS
plot revealed the existence of five groups of species that overlapped in their distribution to some extent. One important
factor that separated the five groups was depth. Other factors that might have been important in structuring the vertical
distribution of the fish fauna, such as bottom topography and sediment type, could not be investigated. Species composition
was dominated by a few abundant low-Antarctic species. In four of the five groups, G. gibberifrons was by far the most abundant species, after C. gunnari and N. rossii had been largely eliminated due to fishing. Only in the 100- to 200-m depth range was C. gunnari more abundant than G. gibberifrons. In the 400- to 500-m depth stratum, a high-Antarctic species, Chionodraco rastrospinosus, and Lepidonotothen squamifrons, a species of Patagonian origin which lacks antifreeze glycopeptides, gained some importance. Species richness showed a positive
trend with increasing depth. Evenness and Hill's N1 index were highest in the shallowest and deepest depth strata. Hill's
N2 index was lowest in depth strata 3 and 4, which had the most even distribution of the abundant fish species.
Accepted: 21 May 2000 相似文献
16.
New taxa of Achilini (Achilidae) are described from Baltic amber: Paratesum rasnitsyni gen. et sp. nov., Protomenocria notata gen. et sp. nov., Psycheona variegata gen. et sp. nov., P. striata sp. nov. Protepiptera kaweckii Usinger, 1939 (= Cixidia christinae Lefebvre, Bourgoin et Nel, 2007, syn. nov.) is redescribed with designation of a neotype. “Cixius” testudinarius Germar et Berendt, 1856, “C.” longirostris Germar et Berendt, 1856 and “Oliarus” oligocenus Cockerell, 1910 are transferred to Achilini. A key to the genera of Achilidae known from Baltic amber is provided. 相似文献
17.
Masazumi Mitani 《Primates; journal of primatology》1986,27(4):397-412
Japanese monkeys often exchange the particular vocal sound, “coo,” especially when they feed or move as a group. It was considered
that the “coo” sound had no positive social meaning, perhaps because the “coo” sound network and its function were hidden
behind other behavioral observations. For identification of the vocalizer only from hearing the “coo” sound, three phonetic
values, i.e., the “fundamental,” “duration,” and “formants,” plus other characteristics were used as indices of voiceprints. The results indicated that these were effective for identifying
the vocalizer in two-thirds of the adults in the study troop which was composed of 12 adults and 16 immature members. The
“coo” sound exchange network among the troop members (adults) was drawn on the basis of the voiceprint identification. The
network showed three characteristics as follows: (1) matriarchs of the kin-groups frequently exchanged “coo” sounds with each
other; (2) the other females exchanged “coo” sounds mostly within their own kin-groups; and (3) males seldom participated
in the “coo” sound exchange. This suggests that “coo” sound exchange plays a central role for the matriarch of kin-groups
in binding each kin-group and, ultimately, in binding all members together into an organized troop. 相似文献
18.
Parasites often confront conflicting demands when evaluating and distributing themselves among host individuals, in order to attain maximum reproductive success. We tested two alternative hypotheses about host preference by fleas in relation to the age of their rodent host. The first hypothesis suggests that fleas select adult over juvenile rodents because the latter represent a better nutritional resource (the “well-fed host” hypothesis), whereas the second hypothesis suggests that fleas prefer the weaker and less resistant juveniles because they are easier to colonise and exploit (“poorly fed host” hypothesis). We sampled fleas (Synosternus cleopatrae) on the gerbil (Gerbillus andersoni) in 23 different plots in the Negev desert and found an unequal distribution of fleas between adult and juvenile hosts. Furthermore, flea distribution changed as a function of flea density—from juvenile-biased flea parasitism (the “poorly fed host” hypothesis) at low densities to adult-biased flea parasitism (the “well-fed host” hypothesis) at high densities. Other factors that influenced flea preference were soil temperature and the presence of ticks. These results suggest that host selection is not an explicit alternative choice between adults and juveniles (“well-fed host” versus “poorly fed host” hypotheses), but rather a continuum where the distribution between adults and juveniles depends on host, parasite, and environmentally related factors. 相似文献
19.
Giuseppe C. Zuccarello Alan T. Critchley Jennifer Smith Volker Sieber Genevieve Bleicher Lhonneur John A. West 《Journal of applied phycology》2006,18(3-5):643-651
The systematics and taxonomy of Kappaphycus and Eucheuma (Solieriaceae) is confused and difficult due to morphological plasticity, lack of adequate characters to identify species and commercial names of convenience. These taxa are geographically widely dispersed through cultivation. Commercial, wild and herbarium sources were analysed; molecular markers provided insights into taxonomy and genetic variation, and where sources of genetic variation may be located. The mitochondrial cox2-3 and plastidal RuBisCo spacers were sequenced. There is a clear genetic distinction between K. alvarezii (“cottonii”) and K. striatum (“sacol”) samples. Kappaphycus alvarezii from Hawaii and some samples from Africa are also genetically distinct. Our data also show that all currently cultivated K. alvarezii from all over the world have a similar mitochondrial haplotype. Within Eucheuma denticulatum (“spinosum”) most African samples are again genetically distinct. Our data also suggest that currently cultivated E. denticulatum may have been “domesticated” several times, whereas this is not evident for the cultivated K. alvarezii. The present markers used do not distinguish all the morpho-types known in cultivation (e.g. var. tambalang, “giant” type) but do suggest that these markers may be useful to assess introductions and species identification in samples. 相似文献
20.
Eiko Kan 《Journal of Ethology》1989,7(1):1-6
The syrphid flyEpisyrphus balteatus (de Geer) migrating from maple trees to leguminous plants in mid-April, assesses the qualitative and quantitative value of
pea aphid colonies for securing successful development of her offspring. She selects young and “promising” pea aphid colonies
of small size. This generally agrees with the “buy-futures” ovipositional tactic the syrphid fly adopts when it utilizes the
maple aphids. The advantage of a “buy-futures” ovipositional tactic found in many syrphid species is discussed in comparison
with other aphidophagous insects. 相似文献