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91.
Lisa Gould 《International journal of primatology》1996,17(3):331-347
I examined the vigilance behavior of adult males and females in two groups of ring-tailed lemurs(Lemur catta)during the birth and lactation season at the Beza-Mahafaly Reserve, southwestern Madagascar. I found no sex difference with
respect to the rates of overall vigilance, rates of vigilance toward a potential predator or unfamiliar sound, or rates of
vigilance toward conspecifics from other social groups, nor were there sex differences in the percentage of time spent vigilant
in any of the above categories. Higher-ranking females were vigilant significantly more often toward predators or potential
predators than lower-ranking females were. I detected no relationship between vigilance behavior and dominance rank among
adult males. The alpha female in each group exhibited significantly more vigilance behavior than all other members of her
group. It was predicted that males should exhibit more vigilance behavior than females do, particularly during the birth and
lactation season, when predator pressure is high, if they are benefiting females in this respect. I discuss the results in
the context of this prediction and in terms of how ring-tailed lemur males benefit females, and why they may be tolerated
in social groups. 相似文献
92.
Cloning and characterization of the rice CatA catalase gene, a homologue of the maize Cat3 gene 总被引:3,自引:0,他引:3
We isolated and sequenced a genomic clone (CatA) encoding CAT-A catalase, a homologue of the maize catalase isozyme 3 (CAT-3) from rice (Oryza sativa L.). The 5-upstream non-coding region had very low similarity with the maize Cat3 gene and possible cis elements and sequence motifs in the maize Cat3 gene were not evident, except for TATA and CAAT motifs. Several sequence motifs found in the promoters of plant seed-specific genes were identified in the 5-upstream non-coding region of the CatA gene. Northern blotting showed that the CatA gene is expressed at high levels in seeds during early development and also in young seedlings. Methyl viologen (paraquat) resulted in the 3-fold induction of the CatA gene in the leaves of young seedlings, whereas abscisic acid, wounding, salicylic acid, and hydrogen peroxide had no or only slight effects.The 1.9 kb 5-upstream fragment (–1559 to +342) of the CatA gene was fused with the Escherichia coli -glucuronidase (GUS) gene and introduced by electroporation into protoplasts prepared from rice suspension-cultured cells, then the transient expression of the GUS gene was examined. Deletion analysis of this chimeric gene suggested that a weak silencer is located in the region between –1564 to –699. Abscisic acid (ABA) at a final concentration of 10–6 M doubled GUS activity in protoplasts electroporated with the chimeric DNAs having 1.9 to 1.2 kb 5-upstream regions. A sequence highly similar to the Sph box, a motif found in genes modulated by ABA, was found at –266 to –254. Deletion of this region however, did not eliminate the responsiveness to ABA. Expression of the chimeric gene in the protoplasts was not enhanced by stress such as low and high temperature, hydrogen peroxide, methyl viologen, salicylic acid, elicitor, and UV light.The chimeric CatA-GUS plasmid DNAs amplified in the methylation-positive strain, E. coli DH5, showed GUS gene activities, whereas all the chimeric DNAs amplified in the methylation-deficient E. coli JM 110 were completely inactive in the presence or absence of ABA in the culture medium. DNA methylation, especially of either one or both of the deoxyadenosines at the two GATC motifs (one in the first exon and the other in the first intron of the rice CatA gene), appeared to be responsible for the CatA promoter activity identified in the transient assay.author for corresondenceThe nucleotide sequence data reported will appear in the DDBJ EMBL and GenBank Nucleotide Sequence Databases under the accession number D29966. 相似文献
93.
Dr. sc. Heinz W. Kozur Univ.-Doz. Dr. Karl Krainer Univ.-Prof. Dr. Helfried Mostler 《Facies》1996,34(1):123-150
Summary Diverse and abundant trace fossils of the deep-waterNereites ichnofacies have been found in well-dated Early Permian deep-water turbidites (Lercara Formation) of western Sicily (Italy).
Conodonts indicate a latest Artinskian to Cathedralian (late Early Permian) age. Microfossils (pelagic conodonts, albaillellid
Radiolaria, paleopsychrospheric ostracods, foraminiferal associations dominated byBathysiphon), trace fossils (deep-bathyal to abyssalNereites ichnofacies) and sedimentologic data collectively indicate a deep-water environment for the Early Permian turbidites of the
Lercara Formation. The dominance ofAgrichnium and of thePaleodictyon subichnogeneraSquamodictyon andMegadictyon suggests that this icnofauna is closely related in ichnotaxonomic composition to other late Paleozoic deep-water ichnofaunas.
The occurrence ofAcanthorhaphe. Dendrotichnium andHelicoraphe, to date only reported from Cretaceous or Tertiary flysch deposits, suggests that the entire ichnofauna corresponds well
to previously documented Silurian-Tertiary flysch ichnofaunas. Eight new ichnospecies and a new ichnosubgenus,Megadictyon, are described. 相似文献
94.
Prof. Dr. Vitaly G. Kuznetsov 《Facies》1996,34(1):151-157
Summary During the Early Permian deep-water basins existed in the southeastern part of the Russian craton. North and west of the Cis-Ural
foredeep and the Precaspian depression (micro-ocean) carbonate platforms were formed on a shallow-marine shelf during the
Asselian, Sakmarian and Early Artinskian. Reefs developed on the margin of these platforms along the slopes of the Cis-Ural
foredeep and the Precaspian depression. The reefs shifted platform ward in the eastern areas, due to the tectonic subsidence
of the platform margin and at the same time, prograded basinward in the south. Movements of continental blocks from the south
during the Late Artinskian and Kungurian caused the separation of the Early Permian basin of the Russian craton from the Palaeo-Tethys,
followed by evaporite sedimentation in the restricted basins.
The existence of source rocks (bituminous deep-water sediments), thick reservoir rocks (limestones and dolostones), evaporitic
seals and structural as well as stratigraphic traps are responsible for large productive gas and oil fields (e.g., Orenburg
field), some of which are distinctly associated with reef carbonates. 相似文献
95.
Summary Late Arenigian biohermal reef mounds and biostromes within the shallow-marine platform facies of the upper San Juan Formation
of the Precordillera (Western Argentina) represent a new Early Ordovician reef type. The meter-sized reefs are dominated byZondarella communis n.g. n. sp. The new taxon is characterized by domical, bulbous and laminar morphotypes exhibiting growth layers and thin
horizontal and vertical as well as intermingled skeletal elements included within different sets. The fossil maybe compared
with stromatolites and stromatoporoids but an interpretation as primitive stromatoporoids is favoured. 相似文献
96.
Enhanced production and accumulation of free and conjugated polyamines as well as increased activities of their biosynthetic enzymes in plants have been associated with heat stress. Perchloric acid-soluble free, as well as conjugated polyamines, and their metabolic enzymes were studied under 45°C heat stress in callus raised from heat-tolerant and -sensitive rice cultivars. The levels of free and conjugated polyamines, as well as arginine decarboxylase (EC 4.1.1.19) and polyamine oxidase (EC 1.4.34) activities were higher in tolerant than in sensitive callus under non-stressed conditions. Heat stress caused greater accumulation of free and conjugated polyamines in callus of the heat-tolerant cultivar N22 than in that of the heat-sensitive cultivar IR8. In particular, the uncommon polyamines norspermidine and norspermine were detected in cv. N22, which increased appreciably during stress, but they were not detected in callus of cv. IR8. Arginine decarboxylase and polyamine oxidase activities increased to a larger extent in N22 than in IR8 callus during stress, activities that were well correlated with the increased levels of common and uncommon polyamines. Increased levels of transglutaminase activity indicated the high titre of conjugated polyamines. 相似文献
97.
Hiroshi Hasegawa 《Physiologia plantarum》1996,96(2):199-204
Screening for mutants deficient in the high affinity system of nitrate uptake was performed using mutagenized M2 population of rice ( Oryza sativa , cv. Nipponbare or Kinmaze). For selecting mutants, M2 seedlings were transferred individually to 10 ml solution containing 250 μ M potassium nitrate and 500 μ M calcium sulphate at 20 or 28°C. After 6 or 24 h, nitrate concentration of the solution was determined with a nitrate selective electrode and the seedlings showing impaired nitrate uptake were selected as nitrate uptake deficient variants. Of 74 variants, three were confirmed to be mutants with low nitrate uptake ability in the M3 generation. Potassium uptake ability also decreased in the mutants. Three mutants were divided into two groups based on the analysis of nitrate reductase (NR, EC 1.6.6.1) activity and chlorate resistance. Two, NUE13 and NUE36 , had a lower level of NR activity than the original cultivar and were not resistant to chlorate, while the seedlings of NUE50 had the same level of NR activity as the original cultivar and were more resistant to chlorate than the original cultivar. All mutants were resistant to cesium, a toxic ion analogue for potassium, suggesting that the decreased levels of both nitrate and potassium uptake were coupled to the change of plasma membrane H+ -ATPase activity. 相似文献
98.
In short-season soybean production areas, low soil temperature is the major factor limiting plant growth and yield. The decreases in soybean yield at low temperatures are mainly due to nitrogen limitation. Genistein, the most effective plant-to-bacterium signal in the soybean (Glycine max (L.) Merr.) nitrogen fixation symbiosis, was used to pretreat Bradyrhizobium japonicum. We have previously reported that this increased soybean nodulation and nitrogen fixation in growth chamber studies. Two field experiments were conducted on two adjacent sites in 1994 to determine whether the incubation of B. japonicum with genistein, prior to application as an inoculant, or genistein, without B. japonicum, applied onto seeds in the furrow at the time of planting, increased soybean grain yield and protein yield in short season areas. The results of these experiments indicated that genistein-preincubated bradyrhizobia increased the grain yield and protein yield of AC Bravor, the later maturing of the two cultivars tested. Genistein without B. japonicum, applied onto seeds in the furrow at the time of planting also increased both grain and protein yield by stimulation of native soil B. japonicum. Interactions existed between genistein application and soybean cultivars, and indicated that the cultivar with the greatest yield potential responded more to genistein addition. 相似文献
99.
S. G. Nugroho J. Lumbanraja H. Suprapto Sunyoto H. Haraguchi M. Kimura 《Plant and Soil》1996,181(2):287-293
Yearly and seasonal (rainy and dry seasons) variations of CH4 emission from a Sumatra paddy field were measured for 3 years. The mean CH4 emission rates during the growth period were in the range of 16.0–26.1 mg CH4 m-2 h-1 for the chemical fertilizer plots and 23.3–34.9 mg CH4 m-2 h-1 for the plots with rice straw application, respectively. The increase in the amounts of CH4 emission by rice straw application were from 1.3 to 1.6 times. There was no significant difference in the mean CH4 emission rates between rainy and dry seasons.Total amounts of CH4 emitted during the period of rice growth were in the ranges of 29.5–48.2 and 43.0–64.6 g CH4 m-2 for the plots applied with chemical fertilizer and those with rice straw application, respectively. Nearly the same amounts of CH4 were emitted in the first and second half of the growth period, irrespective of rice straw application. 相似文献
100.