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31.
Amplified Fragment Length Polymorphism (AFLP) Provides Molecular Markers for the Identification of Caladium bicolor Cultivars 总被引:4,自引:0,他引:4
LOH JIN PHANG; KIEW RUTH; KEE ANDREA; GAN LEONG HUAT; GAN YIK-YUEN 《Annals of botany》1999,84(2):155-161
Caladiums are popular ornamental plants that have not been wellstudied at the molecular level. Identification of species withinthe genus Caladium (Araceae) has been based primarily on morphology.However, the lack of comprehensive references makes identificationof Caladium cultivars extremely difficult. Amplified fragmentlength polymorphism (AFLP) analysis using 17 primer combinationswas carried out on two species of Caladium (C. bicolor and C.schomburgkii), including six cultivars of C. bicolor. Resultsshowed that AFLP can be used to distinguish these two speciesby their unique and different banding patterns. Unweighted PairGroup Method using Arithmetic Averages (UPGMA) permitted clusteranalysis of data from 17 selected primer combinations on sixcultivars of C. bicolor and one cultivar ofC. schomburgkii .It showed that closely related species can clearly be differentiatedand that genetic difference between cultivars can also be established.Unique AFLP molecular markers were detected for all the C. bicolorcultivars used. The use of AFLP has potential for preciselycharacterizing and identifying particular caladium cultivarsas well as for the registration of new cultivars. It will alsobe useful in future breeding programmes and systematics studies.Copyright 1999 Annals of Botany Company Araceae, Caladium species and cultivars, AFLP DNA fingerprinting, diversity, AFLP markers. 相似文献
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ARTURO ARGÜELLO RUTH DEL PRADO PALOMA CUBAS ANA CRESPO 《Biological journal of the Linnean Society. Linnean Society of London》2007,91(3):455-467
Morphological and phylogenetic relationships of the worldwide Mediterranean lichen forming fungus, Parmelina quercina , have been studied. Specimens from western Europe, western North America and southern Australia were analysed using molecular data (nuITS rDNA, nuLSU rDNA and mtSSU rDNA) and selected morphological features (upper cortex maculae, scanning electron microscopy examination of the epicortex, ascospores and conidia shape and size, and amphithecial retrorse rhizines). The results conclusively reveal that: (1) there is not one single species but four separate species in the Mediterranean or sub Mediterranean areas of the world. Parmelina quercina and Parmelina carporrhizans (Euroasiatic species), Parmelina coleae sp. nov. (North America) and Parmelina elixia sp. nov. (Australia); (2) largely debated P. carporrhizans is not a synonym of P. quercina but supported as a valid species circumscribed to Macaronesic relict sites; (3) the geographical isolation of the Australian population is correlated with a large genetic distance; (4) morphological characters (ascospores and conidial variability and thallus epicortex) correlate with the phylogenetic hypothesis; (5) the new or revalidated species within Parmelina quercina are not cryptic species but morphologically recognizable taxa. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 455–467. 相似文献
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Mitochondria isolated from lettuce seeds and seedlings are capableof hydrolyzing ATP. On basis of pH optima, there are at leasttwo and probably three enzymes possessing ATPase activity. Oneof them is inhibited by EDTA and all of them are inhibited byNaF. The ATP ase activity of the mitochondria is very slight in imbibedseeds but increases considerably with seedling growth. Othercomponents of the cell also contain ATP hydrolyzing enzymes;however, most of these phosphatases in the seedling seem tobe soluble enzymes. (Received December 12, 1961; ) 相似文献
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RUTH HALABAN 《Pigment cell & melanoma research》1988,1(Z1):18-26
To proliferate in vitro, normal melanocytes, unlike normal fibroblasts, require specific growth factors in addition to those supplied in serum. The substances that promote melanocyte proliferation, such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and stimulators of cyclic adenosine monophosphate (cAMP), also promote pigmentation. Consequently, cell division and expression of at least some differentiated functions are not mutually exclusive for melanocytes. At present, the only known natural growth factor that can replace TPA in normal human melanocyte cultures is basic fibroblast growth factor (bFGF). Like TPA, bFGF is effective, most of the time, only in the presence of added cAMP. Some preparations of bFGF, however, may have a highly labile, intrinsinc cAMP stimulatory activity. It is thus possible that bFGF can assume two forms, dependent on and independent of cAMP stimulatory activity. Alternatively, a second factor may exist in pituitary glands that co-purifies with bFGF but deteriorates with storage. Abnormal melanocytes in culture, such as those derived from dysplastic nevi and primary melanomas, depend on the specific factors (bFGF and cAMP), whereas melanocytes from metastatic melanomas do not 相似文献
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A protein, which consists of a defined sequence of amino-acids, can be converted into another protein of equal length by changes in the sequence of nucleotides in the segment of DNA by which it is coded. It is convenient to term this segment a gene. Most proteins are 200–400 amino-acids long, so that most genes, if defined in this way, are represented by 600–1,200, or about 103, nucleotides. The evolution of protein molecules may appear to be limited by the need for each step in the sequence to be at a selective advantage. Maynard Smith1 has compared this with a word game in which, using exclusively meaningful words, one word has to be changed to another by altering one letter at a time. 相似文献
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ANTONIANA KRETTLI DAVID H. CHEN RUTH S. NUSSENZWEIG 《The Journal of eukaryotic microbiology》1973,20(5):662-665
Sporozoites of rodent and simian malaria (Plasmodium berghei and P. cynomolgi) were purified by centrifugation on a linear Renografin/BSA gradient. This procedure made it possible to process rapidly a large number of infected mosquitoes leading to the recovery of a considerable proportion of sporozoites. Gradient-recovered sporozoites (GRS) freed of most bacteria and mosquito tissue contaminants, retained their infectivity and immunogenicity. Mice repeatedly injected i.v. with irradiated GRS of P. berghei acquired total protection against an otherwise lethal sporozoite challenge. GRS of P. berghei and P. cynomolgi induced antisporozoite (CSP) antibody production in rats. 相似文献
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SUMMARY: Ignoring wasted material at the surface and sides, the variation in pH in six months old pit silage was smaller from side to side than from top to bottom. At the 2-foot level, where the best quality silage was found, variation was very slight. A correlation was found between pH and the logarithm of the microscopical count of bacteria, the total number of bacteria falling with decreasing pH. 相似文献
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Comparison by soil-block tests on several timbers of the wood-destroyingabilities of dicaryotic cultures of both Poria vaillantii andLenzites trabea with those of monocaryotic cultures either derivedfrom, or contributing to, the formation of the dicaryon, indicatedthat monocaryotic cultures of P. vaillantii were generally moredestructive than related dicaryotic cultures, whereas dicaryonsof L. trabea tended to be slightly more destructive than relatedmonocaryons. The tolerance of L. trabea monocaryons to coppersulphate and to sodium arsenate in nutrient agar showed someindication of being higher than that of related dicaryons, whilstthe tolerance of P. vaillantii monocaryons to a copperchrome-arsenatepreservative in soil-block tests also appeared to be higherthan that of related dicaryons. It is concluded that, althoughneither wood-destroying ability nor preservative tolerance wasgreatly affected by nuclear condition, the differences shownmay be of importance in conjunction with the monocaryotizationof dicaryons by toxic agents during laboratory decay tests. 相似文献