Variation in Ploidy Levels and Reproductive Pathways Among Flowering Crabapples

Information on ploidy levels is extremely valuable for use in plant breeding programs. Fertility, crossability, and heritability of traits are all influenced by ploidy levels. Knowledge of reproductive pathways, including occurrence of apomixes, pseudogamy, and formation of unreduced gametes can also be important information for developing breeding strategies. Although ploidy level can be determined by counting chromosomes, flow cytometry provides a reliable and much faster means for determination of nuclear DNA content and associated ploidy level. Measurement of ploidy levels of seeds (embryo and endosperm) can also provide useful insights into reproductive pathways. The objective of this study was to determine the approximate genome size, estimated ploidy level, and range of reproductive pathways of a diverse collection of flowering crapbapples (Malus spp.). Genome sizes were calculated as nuclear DNA content for unreduced tissue (2C). Results from the taxa included in our survey showed DNA contents ranging from 1.52 to 1.82 for diploids, 2.40 to 2.62 for triploids, and 3.36 to 3.74 pg/2C for tetraploids. Based on these ranges, we identified 43 diploid, 10 triploid, and 4 tetraploid crabapple taxa in this collection. Results from open pollinated seeds and seedlings demonstrated a variety of reproductive pathways including apomixes and unreduced gametes. This research provides information on ploidy levels and reproductive pathways of flowering crabapples and will allow for more systematic and efficient progress in the development of improved cultivars.

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Nuclear DNA amount in pure species and hybrid willows (Salix): a flow cytometric investigation

Canadian Journal of Botany ◽

10.1139/b97-153 ◽

1998 ◽

Vol 76 (1) ◽

pp. 157-165 ◽

Cited By ~ 6

Author(s):

Jérôme Thibault

Keyword(s):

Flow Cytometry ◽

Ploidy Level ◽

Dna Content ◽

Nuclear Dna ◽

Nuclear Dna Content ◽

Natural Hybridization ◽

Ploidy Levels ◽

Key Words Flow Cytometry ◽

Dna Values ◽

Dna Amounts

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.

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Chromosome Number, Ploidy Level, and Nuclear DNA Content in 23 Species of Echeveria (Crassulaceae)

Genes ◽

10.3390/genes12121950 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1950

Author(s):

Guadalupe Palomino ◽

Javier Martínez-Ramón ◽

Verónica Cepeda-Cornejo ◽

Miriam Ladd-Otero ◽

Patricia Romero ◽

...

Keyword(s):

Flow Cytometry ◽

Chromosome Number ◽

Ploidy Level ◽

Dna Content ◽

Chromosome Numbers ◽

Nuclear Dna ◽

Nuclear Dna Content ◽

Root Tips ◽

Ploidy Levels ◽

Dna Amounts

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.

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Determining Ploidy Level and Nuclear DNA Content in Rubus by Flow Cytometry

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.127.5.767 ◽

2002 ◽

Vol 127 (5) ◽

pp. 767-775 ◽

Cited By ~ 37

Author(s):

Rengong Meng ◽

Chad Finn

Keyword(s):

Flow Cytometry ◽

Pacific Northwest ◽

Ploidy Level ◽

Dna Content ◽

Chromosome Numbers ◽

Nuclear Dna ◽

Diploid Species ◽

Nuclear Dna Content ◽

Dna Flow Cytometry ◽

Ploidy Levels

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).

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Determination of Ploidy Level and Nuclear DNA Content in Tunisian Populations of Atriplex halimus L.

Genetic Resources and Crop Evolution ◽

10.1007/s10722-005-5806-4 ◽

2005 ◽

Vol 53 (1) ◽

pp. 1-5 ◽

Cited By ~ 7

Author(s):

Kheiria Hcini ◽

David J. Walker ◽

Sadok Bouzid ◽

Elena González ◽

Nora Frayssinet ◽

...

Keyword(s):

Ploidy Level ◽

Dna Content ◽

Nuclear Dna ◽

Nuclear Dna Content ◽

Atriplex Halimus

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Determination of Ploidy Level and Nuclear DNA Content in the Droseraceae by Flow Cytometry

CYTOLOGIA ◽

10.1508/cytologia.82.321 ◽

2017 ◽

Vol 82 (3) ◽

pp. 321-327 ◽

Cited By ~ 3

Author(s):

Yoshikazu Hoshi ◽

Masako Azumatani ◽

Chika Suyama ◽

Lubomίr Adamec

Keyword(s):

Flow Cytometry ◽

Ploidy Level ◽

Dna Content ◽

Nuclear Dna ◽

Nuclear Dna Content

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NUCLEAR DNA CONTENT AND PLOIDY LEVEL IN APOMICTIC BUFFELGRASS GENOTYPES

Revista Fitotecnia Mexicana ◽

10.35196/rfm.2018.1.23-29 ◽

2018 ◽

Vol 41 (1) ◽

pp. 23-29

Author(s):

Edgardo J. Carloni-Jarrys ◽

Ma. Cristina Acosta-Bragato ◽

Karina Grunberg-Fraga

Keyword(s):

Ploidy Level ◽

Dna Content ◽

Nuclear Dna ◽

Dna Ploidy ◽

Nuclear Dna Content ◽

Agricultural Technology ◽

Ploidy Levels ◽

Field Collection ◽

Fodder Grass ◽

Tetraploid Cytotypes

Buffelgrass [Pennisetum ciliare (L.) Link syn. Cenchrus ciliaris L.] is a polyploid fodder grass that reproduces mostly via apomixis. The wide genomic and cytological diversity present in the species indicates that the active field collection at Instituto de Fisiología y Recursos Genéticos Vegetales (IFRGV) of the National Institute of Agricultural Technology (INTA) might contain individuals with different ploidy levels. This researche aimed to determine nuclear DNA content and ploidy level of introduced apomictic germplasm of buffelgrass. Cytological studies showed different ploidy levels in the germplasm. Genetic resources include tetraploid (2n = 4x = 36) and aneuploid (2n = 43 and 44) individuals. The 10 materials that exhibited 2C values ranging between 3.04 and 3.17 pg were tetraploid cytotypes. The values of the four aneuploid individuals with 43 chromosomes ranged between 3.83 and 3.86 pg, whereas aneuploid individual with 44 chromosomes had a 2C value of 3.94 pg. Number of chromosomes and nuclear DNA content were correlated. In addition, a model equation was obtained to estimate DNA ploidy value in buffelgrass genotypes.

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