scholarly journals Nuclear DNA Contents of Phalaenopsis sp. and Doritis pulcherrima

2001 ◽  
Vol 126 (2) ◽  
pp. 195-199 ◽  
Author(s):  
Sandy Lin ◽  
Hsiao-Ching Lee ◽  
Wen-Huei Chen ◽  
Chi-Chang Chen ◽  
Yen-Yu Kao ◽  
...  

Nuclear DNA contents were estimated by flow cytometry in 18 Phalaenopsis Blume species and Doritis pulcherrima Lindl. DNA amounts differed 6.07-fold, from 2.74 pg/diploid nuclear DNA content (2C) in P. sanderiana Rchb.f. to 16.61 pg/2C in P. parishii Rchb.f. Nuclear DNA contents of P. aphrodite Rchb.f. clones, W01-38 (2n = 2x = 38), W01-41 (2n = 3x = 57), and W01-22 (2n = 4x = 76), displayed a linear relationship with their chromosome numbers, indicating the accuracy of flow cytometry. Our results also suggest that the 2C-values of the Phalaenopsis sp. correlate with their chromosome sizes. The comparative analyses of DNA contents may provide information to molecular geneticists and systematists for genome analysis in Phalaenopsis. Endoreduplication was found in various tissues of P. equestris at different levels. The highest degree of endoreduplication in P. equestris was detected in leaves.

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
B. J. M. Zonneveld

Genome size (C-value) was applied anew to investigate the relationships within the genus Hepatica (Ranunculaceae). More than 50 samples representing all species (except H. falconeri), from wild and cultivated material, were investigated. Species of Hepatica turn out to be diploid (), tetraploid ( ), and a possible pentaploid. The somatic nuclear DNA contents (2C-value), as measured by flow cytometry with propidium iodide, were shown to range from 33 to 80 pg. The Asiatic and American species, often considered subspecies of H. nobilis, could be clearly distinguished from European H. nobilis. DNA content confirmed the close relationships in the Asiatic species, and these are here considered as subspecies of H. asiatica. Parents for the allotetraploid species could be suggested based on their nuclear DNA content. Contrary to the increase in genome size suggested earlier for Hepatica, a significant (6%–14%) loss of nuclear DNA in the natural allopolyploids was found.


Genes ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1950
Author(s):  
Guadalupe Palomino ◽  
Javier Martínez-Ramón ◽  
Verónica Cepeda-Cornejo ◽  
Miriam Ladd-Otero ◽  
Patricia Romero ◽  
...  

Echeveria is a polyploid genus with a wide diversity of species and morphologies. The number of species registered for Echeveria is approximately 170; many of them are native to Mexico. This genus is of special interest in cytogenetic research because it has a variety of chromosome numbers and ploidy levels. Additionally, there are no studies concerning nuclear DNA content and the extent of endopolyploidy. This work aims to investigate the cytogenetic characteristics of 23 species of Echeveria collected in 9 states of Mexico, analyzing 2n chromosome numbers, ploidy level, nuclear DNA content, and endopolyploidy levels. Chromosome numbers were obtained from root tips. DNA content was obtained from the leaf parenchyma, which was processed according to the two-step protocol with Otto solutions and propidium iodide as fluorochrome, and then analyzed by flow cytometry. From the 23 species of Echeveria analyzed, 16 species lacked previous reports of 2n chromosome numbers. The 2n chromosome numbers found and analyzed in this research for Echeveria species ranged from 24 to 270. The range of 2C nuclear DNA amounts ranged from 1.26 pg in E. catorce to 7.70 pg in E. roseiflora, while the 1C values were 616 Mbp and 753 Mbp, respectively, for the same species. However, differences in the level of endopolyploidy nuclei were found, corresponding to 4 endocycles (8C, 16C, 32C and 64C) in E. olivacea, E. catorce, E. juarezensis and E. perezcalixii. In contrast, E. longiflora presented 3 endocycles (8C, 16C and 32C) and E. roseiflora presented 2 endocycles (8C and 16C). It has been suggested that polyploidization and diploidization processes, together with the presence of endopolyploidy, allowed Echeveria species to adapt and colonize new adverse environments.


2009 ◽  
Vol 57 (6) ◽  
pp. 524 ◽  
Author(s):  
Milene Miranda Praça ◽  
Carlos Roberto Carvalho ◽  
Carolina Ribeiro Diniz Boaventura Novaes

Previous flow cytometry (FCM) analyses delivered nearly equal mean values of nuclear 2C DNA content for Eucalyptus grandis Hill ex Maiden and E. urophylla S. T. Blake (1.33 pg and 1.34 pg, respectively), whereas E. globulus Labill. presented distinct mean values (1.09, 1.13 and 1.40). These differences have been attributed to the different methodological approach, utilised plant cultivar and presence of intrinsic metabolic compounds that affect fluorochrome fluorescence. In the present study, a FCM and image cytometry (ICM) design, following international consensus criteria, were adopted to reassess the nuclear DNA contents of the above-mentioned Eucalyptus species. Statistical analyses revealed either similar or discrepant nuclear DNA contents, depending on the standard species used and whether FCM or ICM was employed. Our results demonstrated that 2C DNA values obtained by FCM and ICM were most uniform when Solanum lycopersicum was used as a standard. Moreover, the values obtained for E. grandis and E. urophylla were close, but differed as much as 24.63% in relation to previous data, and E. globulus proportionally varied up to 25%. New DNA content values are suggested for these eucalypt species.


1998 ◽  
Vol 76 (1) ◽  
pp. 157-165 ◽  
Author(s):  
Jérôme Thibault

Flow cytometry (FCM) has been used to estimate the nuclear DNA content of 11 Salix species and 5 hybrids. One hundred and sixty nine individuals were studied including 159 individuals from a sequence of 32 communities along a stretch of river in France and 10 individuals from French and English collections for comparison. Isolated nuclei were stained with propidium iodide. FCM was a significantly more practical and rapid technique than that of establishing the karyotype to survey many samples of Salix for variation in ploidy. The 2C DNA amounts for diploid species ranged from 0.76 to 0.98 pg, and tetraploid values ranged from 1.62 to 1.80 pg. The DNA values were consistent with the known ploidy levels. With the exception of a doubtful Salix xquercifolia, ploidy levels and DNA amounts of hybrids were intermediate compared with those of their parents. Intraspecific variation of nuclear DNA values including instrumental variation was low (i.e., 6-11% at the same ploidy level). FCM appeared to be an accurate tool for determination of Salix triploid hybrids. However, it remains limited concerning hybrids from crosses between species of the same ploidy level. Results suggest that natural hybridization might not be frequent in the communities studied, although they have been subject to disturbance. Previous overestimates of hybridization frequency in willows were probably due to misinterpretation of the effects of the environment on Salix spp. morphology; however, the extent and mechanisms of introgression in the genus remain to be further investigated. Key words: flow cytometry, Salix, hybridization, nuclear DNA content, riparian vegetation, disturbance.


2002 ◽  
Vol 127 (5) ◽  
pp. 767-775 ◽  
Author(s):  
Rengong Meng ◽  
Chad Finn

Nuclear DNA flow cytometry was used to differentiate ploidy level and determine nuclear DNA content in Rubus. Nuclei suspensions were prepared from leaf discs of young leaves following published protocols with modifications. DNA was stained with propidium iodide. Measurement of fluorescence of 40 genotypes, whose published ploidy ranged from diploid to dodecaploid, indicated that fluorescence increased with an increase in chromosome number. Ploidy level accounted for 99% of the variation in fluorescence intensity (r2 = 0.99) and variation among ploidy levels was much higher than within ploidy levels. This protocol was used successfully for genotypes representing eight different Rubus subgenera. Rubus ursinus Cham. and Schldl., a native blackberry species in the Pacific Northwest, which has been reported to have 6x, 8x, 9x, 10x, 11x, and 12x forms, was extensively tested. Genotypes of R. ursinus were predominantly 12x, but 6x, 7x, 8x, 9x, 11x, and 13x forms were found as well. Attempts to confirm the 13x estimates with manual counts were unsuccessful. Ploidy level of 103 genotypes in the USDA-ARS breeding program was determined by flow cytometry. Flow cytometry confirmed that genotypes from crosses among 7x and 4x parents had chromosome numbers that must be the result of nonreduced gametes. This technique was effective in differentiating chromosome numbers differing by 1x, but was not able to differentiate aneuploids. Nuclear DNA contents of 21 diploid Rubus species from five subgenera were determined by flow cytometry. Idaeobatus, Chamaebatus, and Anaplobatus were significantly lower in DNA content than those of Rubus and Cylactis. In the Rubus subgenus, R. hispidus and R. canadensis had the lowest DNA content and R. sanctus had the highest DNA content, 0.59 and 0.75 pg, respectively. Idaeobatus had greater variation in DNA content among diploid species than the Rubus subgenus, with the highest being from R. ellipticus (0.69 pg) and lowest from R. illecebrosus (0.47 pg).


1971 ◽  
Vol 13 (3) ◽  
pp. 607-611 ◽  
Author(s):  
Michael D. Bennett ◽  
J. B. Smith

The 4C nuclear DNA content was estimated for 17 wild Hordeum species and five cultivated Hordeum vulgare varieties which were chosen to include examples varying greatly in geographical origin and in morphological and physiological characters. Nuclear DNA was measured on an integrating microdensitometer using prophase nuclei in Feulgen stained root-tip squashes. There were no significant differences in DNA content between any or the 15 diploid genotypes measured, and the seven polyploid genotypes all had nuclear DNA contents which were simple multiples of the diploid genotypes. This result, namely that the DNA content of diploid Hordeum species is invariable, differs from results obtained from diploid species in several other plant genera which differed greatly in nuclear DNA content.


Genome ◽  
1987 ◽  
Vol 29 (2) ◽  
pp. 374-379 ◽  
Author(s):  
K. H. Keeler ◽  
B. Kwankin ◽  
P. W. Barnes ◽  
D. W. Galbraith

The relationship between nuclear DNA content and chromosome number was investigated in Andropogon gerardii. The distribution of cytotypes in a natural population of this grass was also examined. Nuclear DNA content was determined using flow cytometry rather than the traditional method of Feulgen microphotometry. Our results demonstrate the increased accuracy and speed of this new method in the detection and study of polyploidy. Nuclear DNA content is strongly correlated to chromosome number in Andropogon gerardii (r = 0.971, P <0.01). The natural population of this grass was found to consist of plants with 2N = 60 chromosomes (hexaploid cytotype) and 2N = 80 chromosomes (octoploid cytotype), in equal proportions. Intermediate cytotypes were lacking in the natural population, although three progeny plants grown in the greenhouse from wild-collected seed show intermediate values of nuclear DNA content and have 2N = 70 chromosomes. The two coexisting cytotypes are intermingled and show no difference in microhabitats. The absence of septaploids in the natural population suggests that the two cytotypes are probably reproductively isolated. Key words: polyploidy, DNA contents, flow cytometry, polymorphism.


2014 ◽  
Vol 57 (3) ◽  
pp. 303-316 ◽  
Author(s):  
Barbara Damsz ◽  
Piotr Łuchniak

Cytophotometric studies of nuclear DNA content after Feulgen procedure indicate that in mesophyll of all the seven studied species the highest nuclear DNA endoreplication level occurs in II or III leaf and it varies for particular species. No differences were found in nuclear DNA endoreplication dynamics between the basal and apical parts of the leaf blade. Chloroplast number per cell generally decreases in the successive leaves, and the plastid index is the smallest in the first (oldest) leaves, being similar in both zones. In four species chloroplast number and plastid index show relatively low negative correlation with nuclear DNA contents (expressed as endoreplication index), in two species this correlation is positive, and one species displays very low r value.


1985 ◽  
Vol 27 (1) ◽  
pp. 47-50 ◽  
Author(s):  
J. B. Anderson ◽  
D. M. Petsche ◽  
A. L. Franklin

The relative nuclear DNA contents of haploid, diploid, and benomyl-induced segregants of diploid strains of the phytopathogenic fungus Armillaria mellea were measured by mithramycin staining and fluorescence photometry. The diploid strains, originally recovered from sexually compatible matings of haploid strains, were heterozygous at mating-type and auxotrophic marker loci. The somatic segregants examined here were derived by treatment of the diploid strains with the fungicide benomyl in previous studies. As expected, the diploid strains had approximately twice as much nuclear DNA as the haploid strains. Most segregants had near-haploid DNA contents and no detectable heterozygosity at the marker loci; these strains were most likely true haploids. Other segregants with near-haploid DNA contents were heterozygous at a marker locus indicating that they were aneuploid. A minority of segregants had near-diploid DNA contents and may have been either aneuploid or diploid.Key words: basidiomycetes, mithramycin, parasexuality.


Sign in / Sign up

Export Citation Format

Share Document