共查询到20条相似文献,搜索用时 15 毫秒
1.
R. Danti G. Della Rocca B. Mori G. Torraca R. Calamassi M. Mariotti Lippi 《Plant Systematics and Evolution》2010,287(3-4):167-177
The aim of this work was to collect new information about pollen morphology and pollen wall structure comparing Cupressus species from the Old World and New World. Cupressus is a nonmonophyletic genus that includes species that appear to be divided into Old World and New World clades. Observations in this study on cypress pollen indicate that grain size and composition of intine β-glucans are different between the considered Old World and New World species. Different from all the other American cypress species, pollen of C. macrocarpa reacted to dying in a similar manner to Old World species. Rehydrated pollen grains collected from 20 Asian, Afro-Mediterranean and American cypress species were measured under a light microscope. The size of the pollen grains and the percentage of intine in relation to the pollen grain diameter were significantly different between Old World and New World species. Pollen wall composition was tested after addition of different dyes to the hydration solution, and subsequent observations were carried out by light and fluorescence microscopy. Lugol and calcofluor staining showed differences in composition of the middle and inner intine layers between New World and Old World species. 相似文献
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The nucellar beak is a proboscis-like outgrowth of the nucellus at the micropylar end, being the obligatory path for the pollen tube entering the ovule. Among the few angiosperm families with nucellar beak, Cucurbitaceae is remarkable because the pollen tube may develop at least two types of growth within the nucellar beak: tubular and ampulliform. Wondering about the possibility that Cucurbitaceae ovules may express some histological variation that could be related to pollen tube growth within the nucellar beak, we performed a compared anatomical and histochemical study of the nucellar beak and the pollen tube growth of ten species of Cucurbitaceae. Results show that Cucurbitaceae ovules are diverse in size and proportions (of integuments, nucellar body, and nucellar beak), and they have at least four types of nucellar beak histology: pectic-tracked, secretory-like, amylaceous, and mixed. Amylaceous and mixed nucellar beaks are related to the ampulliform growth of the pollen tube, which could have appeared independently in most derived tribes of Cucurbitaceae, although information about nucellar beak structure in the basal tribes is still needed. In addition, the understanding of the relation between amylaceous nucellar beaks and the ampulliform growth of the pollen tube, whose function is still to be discovered, might open the possibility of a unique model of pollen tube-ovule co-evolution in angiosperms. 相似文献
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The development of plastids in the pollen of Cucurbita pepo was followed from meiosis to pollen maturation by quantitative light and electron microscopy. Plastids are initially undifferentiated, then divide, and at late microspore stage differentiate into amyloplasts containing starch. Later the amyloplasts form lobes and divide. Amyloplasts containing a single starch grain are present from the early bicellular stage. Plastid development is considered in relation to such cytoembryological features as the pollen does not dehydrate at anthesis and germination begins 3 min after pollination. 相似文献
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Mats Thulin 《Nordic Journal of Botany》1996,16(3):297-300
The new species Zehneria somalensis , from shady limestone rocks in north-eastem Somalia, is described and illustrated. 相似文献
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Z V Shevtsova B A Lapin N V Doroshenko R I Krilova L I Korzaja I B Lomovskaya Z N Dzhelieva G K Zairov V M Stakhanova E G Belova 《Journal of medical primatology》1988,17(4):177-194
Virologic, serologic, biochemical, and morphological data characterizing spontaneous hepatitis A (HA) in cynomolgus macaques (Macaca fascicularis) and green monkeys (Cercopithecus aethiops) are reported. Experimental HA was induced in macaques as a result of infection with human hepatitis A virus (HAV-h). Disease similar to human HA was induced in cynomolgus macaques by HAV isolates from spontaneously sick rhesus (M. mulatta) and green monkeys. This experimental model of HA in macaques can be used for vaccine and anti-viral preparation testing. 相似文献
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Jennie V. A. Dieterle 《Brittonia》1974,26(2):129-132
Apatzingania, described here as new, is represented by one species:A. arachoidea Dieterle. The position of the genus in the family is discussed, particularly its relationship toBrandegea, Vaseyanthus, andEchinopepon. 相似文献
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Mats Thulin 《Nordic Journal of Botany》1991,11(4):425-427
Momordica littorea , sp. nov., a dioecious climber with succulent 3-foliolate leaves and conspicuously bracteate flowers from coastal regions of southern Somalia and Kenya, is described and illustrated. 相似文献
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Richard P. Wunderlin 《Brittonia》1976,28(2):239-244
The monotypic genusPolakowskia is reduced to a section ofFrantzia. Two new species from Costa Rica,F. villosa andF. talamancensis, are described. The new nomenclatural combination,F. tacaco (Pittier) Wunderlin, is proposed. 相似文献
12.
Sicyos motozintlensis is described from the vicinity of Motozintla de Mendoza, Chiapas. It shows a strong similarity toS. chiriquensis Hammel & D’Arcy from Panama. 相似文献
13.
Wayne L Gray 《Comparative medicine》2008,58(1):22-30
Simian varicella virus (SVV) causes a natural erythematous disease in Old World monkeys and is responsible for simian varicella epizootics that occur sporadically in facilities housing nonhuman primates. This review summarizes the biology of SVV and simian varicella as a veterinary disease of nonhuman primates. SVV is closely related to varicella–zoster virus, the causative agent of human varicella and herpes zoster. Clinical signs of simian varicella include fever, vesicular skin rash, and hepatitis. Simian varicella may range from a mild infection to a severe and life-threatening disease, and epizootics may have high morbidity and mortality rates. SVV establishes a lifelong latent infection in neural ganglia of animals in which the primary disease resolves, and the virus may reactivate later in life to cause a secondary disease corresponding to herpes zoster. Prompt diagnosis is important for control and prevention of epizootics. Antiviral treatment for simian varicella may be effective if administered early in the course of infection.Abbreviations: FEAU, 1-(2′-deoxy-2′-flouro-β-D-arabinofuranosyl)-5-iodouracil, IE, immediate early, ORF, open reading frame, PBL, peripheral blood lymphocyte, SVV, simian varicella virus, VZV, varicella–zoster virusSimian varicella is a natural erythematous disease of Old World primates (Superfamily Cercopithecoidea, Subfamily Cercopithecinae), involving particularly patas (Erythrocebus patas), African green or vervet (Chlorocebus aethiops), and various species of macaque (Macaca spp.) monkeys. Epizootics of simian varicella occur sporadically in facilities housing nonhuman primates. These outbreaks are sometimes associated with high morbidity and mortality and the loss of valuable research animals. Simian varicella virus (SVV; Cercopithecine herpesvirus 9), a primate herpesvirus, is the etiologic agent of the disease. SVV is antigenically and genetically related to varicella–zoster virus (VZV; Human herpesvirus 3), the cause of human varicella (chickenpox) and herpes zoster (shingles). The clinical similarities between simian and human varicella and the relatedness of SVV and VZV, indicate that SVV infection of nonhuman primates is a useful model for study of varicella pathogenesis and development of antiviral therapies. A previous comprehensive review emphasized simian varicella as an experimental model for VZV infections.22 This review focuses on simian varicella as a veterinary disease of nonhuman primates. Simian varicella outbreaks and their epidemiology are considered, and the etiologic agent, clinical manifestations, pathogenesis, diagnosis, treatment, and control of the disease are discussed. 相似文献
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There is a spreading interest to establish networks of information exchange on aerobiological data in order to carry out comparative studies of the biological air content of different regions. For this kind of study, it is of primary importance that the methods used are being standardized. Since most national networks are now made of comparable Hirst-type samplers, the second most important factor to consider will be the efficiency of the adhesive used on the Melinex tape. In this study, we report conclusive results using a double-side self adhesive acrylic tape (Scotch 3M 9425). Our results show higher capture efficiency (+20%) for the 3M tape as compared to the glycerine/gelatine coating traditionally used in Montréal for the capture of airborne pollen on the Melinex tape of Hirst samplers. 相似文献
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A new procedure to asses pollen viability 总被引:4,自引:0,他引:4
We tested pollen viability of eight species using four vital dyes, a new peroxidase test together with three other established
methods (MTT, Baker’s and X-Gal), to determine their potential to differentiate fresh pollen from pollen heated for 2 h and
24 h at 80°C (killed pollen) and compared the results with in vitro germination. We found that two of three dyes previously
employed to determine viability also stained killed pollen, while the new peroxidase test and MTT did not. We suggest that
the latter two are the best methods to test pollen viability, since they do not normally stain either killed or aborted pollen.
Received: 7 May 1999 / Revision accepted: 25 October 1999 相似文献
17.
To determine the effects of soil phosphorus on pollen production, pollen grain size, phosphate concentration per pollen grain, and the siring ability of pollen, two cultivars of the common zucchini (Cucurbita pepo) were grown under two soil phosphorus conditions in an experimental garden. Overall, soil phosphorus availability had a significant effect on reproductive output through the female function and on traits affecting the male function of plants (staminate flower production, pollen production per flower, and pollen grain size). In addition, pollen produced by plants in the high phosphorus soils had a higher phosphate concentration than pollen produced by plants in the low phosphorus soils. A pollen mixture experiment revealed that pollen produced by plants in the high phosphorus treatment sired significantly more seeds than pollen produced by plants in the low phosphorus treatment. This study showed that growing conditions such as soil phosphorus can influence the size of a pollen grain and its chemical composition, which, in turn, can affect its ability to sire mature seeds. 相似文献
18.
A mobile element based phylogeny of Old World monkeys 总被引:6,自引:0,他引:6
Xing J Wang H Han K Ray DA Huang CH Chemnick LG Stewart CB Disotell TR Ryder OA Batzer MA 《Molecular phylogenetics and evolution》2005,37(3):388-880
SINEs (Short INterspersed Elements) are a class of non-autonomous mobile elements that are <500 bp in length and have no open reading frames. Individual SINE elements are essentially homoplasy free with known ancestral states, making them useful genetic systems for phylogenetic studies. Alu elements are the most successful SINE in primate genomes and have been utilized for resolving primate phylogenetic relationships and human population genetics. However, no Alu based phylogenetic analysis has yet been performed to resolve relationships among Old World monkeys. Using both a computational approach and polymerase chain reaction display methodology, we identified 285 new Alu insertions from sixteen Old World monkey taxa that were informative at various levels of catarrhine phylogeny. We have utilized these elements along with 12 previously reported loci to construct a phylogenetic tree of the selected taxa. Relationships among all major clades are in general agreement with other molecular and morphological data sets but have stronger statistical support. 相似文献
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The effects of soil fertility (two levels of soil nitrogen and two levels of soil phosphorus) and mycorrhizal infection on pollen production and pollen grain size were studied in two cultivars of the common zucchini (Cucurbita pepo). Overall, soil fertility and mycorrhizal infection had significant effects on traits affecting the male function of plants (staminate flower production, pollen production per flower and pollen grain size). There were also differences between the cultivars for these male traits in all three experiments. In addition, pollen grain size decreased toward the end of the growing season. In the mycorrhiza experiment, both phosphate concentration per pollen grain and total phosphate content per anther were greater but not significantly greater in the mycorrhizal plants than in the non-mycorrhizal plants. A significant negative relationship between pollen production and pollen grain size was found in the mycorrhiza and soil phosphorus experiments, indicating that there was a trade-off between pollen production and pollen size. This study is the first to show that mycorrhizal infection has an effect on male function (pollen production and size) in addition to the well-documented effects on female function (fruit/seed production and size). 相似文献
20.
The use of a double-sided self-adhesive tapefor pollen trapping could offer some advantagesover traditional adhesives, manually applied tothe Melinex tape of a Hirst-type spore trap,since variation in terms of adhesiveapplication is nil and additional effort inapplying the adhesive is avoided. Nevertheless,its efficiency with respect to the standardadhesives must be tested. In Cordoba (southwestSpain), the Spanish Aerobiology Network Centreperformed a series of comparative studies andrecommended the use of a silicone fluid as anadhesive. This paper compares the efficiency ofa double-sided self-adhesive tape (3M) withsilicone fluid as adhesive. Sampling wascarried out using a Hirst type 7-day spore traplocated 15 m above ground level. A Melinex tapecoated with silicone fluid covered one half ofthe weekly drum; the other half was coveredwith 3M tape that included the adhesive. It iswidely reported that the physicalcharacteristics of silicone fluid do not varywith temperature (Galán andDomínguez-Vilches, 1997), but this studyshowed that 3M efficiency did vary withtemperature. The results revealed that 3M tapewas less efficacious at low temperatures, whileat high temperatures it becomes stickier. Incontrast, silicone fluid does not vary withtemperature. The efficiency of 3M tape alsoseems to be negatively influenced by rain. 相似文献