Pachytene Chromosome Morphology in<i>Coffea</i>L. I. Nucleolar Chromosomes

Pinto-Maglio, Cecília Alzira Ferreira; Cruz, Neusa Diniz da

doi:10.1080/00087114.1987.10797806

Cited by 17 publications

(6 citation statements)

References 27 publications

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“…dewevrei exhibited a higher level of differentiation than that commonly observed among botanical varieties. The same is true for flower and fruit morphology and structure of chromosomes attached to the nucleolus investigated by Carvalho (1991) and Pinto-Maglio and Cruz (1987), respectively.…”

Section: Genetic Relationshipsmentioning

confidence: 55%

Genetic diversity of a Coffea Germplasm Collection assessed by RAPD markers

Silvestrini

Maluf

Silvarolla

et al. 2007

Genet Resour Crop Evol

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Genetic diversity and relationships within and among nine species of Coffea, one species of Psilanthus and the Piatã hybrid from the Coffee Germplasm Collection of Instituto Agronô-mico de Campinas (IAC), Brazil were assessed using RAPD markers. Genetic diversity and relationships were evaluated by proportion of polymorphic loci (P), Shannon's genetic index (H 0 and G 0 ST ) and clustering analysis. The overall RAPD variation among all accessions was mostly partitioned between rather than within species. However, C. canephora and C. liberica showed a high genetic diversity within the species (H 0 sp = 0.414 and H 0 sp = 0.380, respectively) and this was highly structured (high G 0 ST ). Genetic diversity from C. congensis and C. arabica was also structured, but with lower levels of genetic diversity (H 0 sp = 0.218 and H 0 sp = 0.126, respectively). The results were consistent with agronomic and molecular studies and demonstrated that the IAC Coffea Collection is representative of the phylogenetic structure observed in the genera. This study devises sampling strategies for coffee germplasm collections and provides genetic diversity parameters for future comparisons among them.

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Section: Genetic Relationshipsmentioning

confidence: 55%

Genetic diversity of a Coffea Germplasm Collection assessed by RAPD markers

Silvestrini

Maluf

Silvarolla

et al. 2007

Genet Resour Crop Evol

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“…The CcEIN4 region is located in the euchromatic part of the C. canephora . Although the organization of gene-rich regions along C. canephora chromosomes remains unknown, previous cytological observations in C. canephora and C. arabica chromosomes have clearly shown a pattern of deeply and lightly staining regions indicating an overall chromosome organization in respectively condensed heterochromatin and decondensed euchromatin regions [ 39 , 40 ]. Similarly to Medicago and tomato chromosome architecture, C. canephora heterochromatin regions are mainly located around centromeric regions while euchromatin constitutes the distal parts of chromosomes [ 13 , 32 ].…”

Section: Discussionmentioning

confidence: 99%

Microcollinearity in an ethylene receptor coding gene region of the Coffea canephora genome is extensively conserved with Vitis vinifera and other distant dicotyledonous sequenced genomes

et al. 2009

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Background Coffea canephora , also called Robusta, belongs to the Rubiaceae, the fourth largest angiosperm family. This diploid species (2x = 2n = 22) has a fairly small genome size of ≈ 690 Mb and despite its extreme economic importance, particularly for developing countries, knowledge on the genome composition, structure and evolution remain very limited. Here, we report the 160 kb of the first C. canephora Bacterial Artificial Chromosome (BAC) clone ever sequenced and its fine analysis. Results This clone contains the CcEIN4 gene, encoding an ethylene receptor, and twenty other predicted genes showing a high gene density of one gene per 7.8 kb. Most of them display perfect matches with C. canephora expressed sequence tags or show transcriptional activities through PCR amplifications on cDNA libraries. Twenty-three transposable elements, mainly Class II transposon derivatives, were identified at this locus. Most of these Class II elements are Miniature Inverted-repeat Transposable Elements (MITE) known to be closely associated with plant genes. This BAC composition gives a pattern similar to those found in gene rich regions of Solanum lycopersicum and Medicago truncatula genomes indicating that the CcEIN4 regions may belong to a gene rich region in the C. canephora genome. Comparative sequence analysis indicated an extensive conservation between C. canephora and most of the reference dicotyledonous genomes studied in this work, such as tomato ( S. lycopersicum ), grapevine ( V. vinifera ), barrel medic M. truncatula , black cottonwood ( Populus trichocarpa ) and Arabidopsis thaliana . The higher degree of microcollinearity was found between C. canephora and V. vinifera , which belong respectively to the Asterids and Rosids, two clades that diverged more than 114 million years ago. Conclusion This study provides a first glimpse of C. canephora genome composition and evolution. Our data revealed a remarkable conservation of the microcollinearity between C. canephora and V. vinifera and a high conservation with other distant dicotyledonous reference genomes. Altogether, these results provide valuable information to identify candidate genes in C. canephora genome and serve as a foundation to establish strategies for whole genome sequencing. Future large-scale sequence comparison between C. canephora and reference sequenced genomes will help in understanding the evolutionary history of dicotyledo...

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“…salvatrix displayed the highest mean values for THCL, χchrom, S (µm) and S%, however, the lowest valtempt to visualize and count the mitotic chromosomes of the ovules. Thenceforth, the studies developed in the genus of species ranged from the identification of the most probable genomes involved in the Arabica origin (Pinto-Maglio and Cruz, 1987), the establishment of the first karyogram and ideogram for C. arabica based on pachytene chromosomes (Pinto-Maglio and Cruz, 1998), following studies in several diploid species to determine the nuclear content (Cros et al, 1998), the heterochromatin localization and quantification in mitotic chromosomes (Pierozzi et al, 1999) and subsequently the heterochromatin molecular composition, as reviewed by Pinto-Maglio (2006) and Hamon et al (2009). The first approaches in coffee chromosome studies however concerned the establishment of chromosome number which led to the finding that wild species are diploid (2n=22) while the Arabica varieties and cultivars are predominantly tetraploid (2n=44) with several hexaploid (2n=66) and octoploid (2n=88) exceptions (Krug, 1934(Krug, , 1945.…”

Section: Resultsmentioning

confidence: 99%

A Karyological Study in Some Species of Coffea L. and in the Closest Relative Psilanthus travancorensis (Wight & Arn.) J.-F. Leroy

Pierozzi

Borghi

Silvarolla

2012

Not Bot Hort Agrobot Cluj

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Chromosome characterization were carried out in Coffea kapakata A. Chev (Bridson), C. racemosa Lour., C. salvatrix Swynn. & Philipson and in Psilanthus travancorensis (Wight & Arn.) J.-F. Leroy (2n=22) by employing the conventional acetic orcein technique as well as by C-and NOR-banding aiming further comparative studies. Although C. canephora and C. dewevrei have already been studied and depict a C-band karyotype, they have also been included for further comparisons, since NOR-banding and some other morphometric data have not been obtained yet. However, there were observed some differences among the species regarding chromosomal morphometry. The karyotype formula obtained was 3m+6sm+2sm s for C. salvatrix and P. travancorensis, 1M +2m + 6sm + 2sm s for C. kapakata and 2M +1m + 6sm + 2sm s for C. racemosa. All species displayed a moderate karyotype asymmetry and according to Stebbins system, C. canephora, C. dewevrei, C. kapakata and C. racemosa were classified as 3B while C. salvatrix and P. travancorensis were classified as 2A. Among the four indices used to assess karyotype asymmetry, Paszko AI index along with Stebbins were best suited to individualize the species. C-bands were preferentially situated at a pericentromeric/centromeric position. Two pairs of chromosomes, with secondary constriction and satellite segments, were observed in all the species following acetic orcein staining. C. racemosa and C. salvatrix showed NOR-band in both pairs, while only one chromosome pair carrying NOR-band was seen in C. canephora, C. dewevrei, C. kapakata and P. travancorensis. Data on chromosome morphometry, asymmetry indices and NOR-banding were suitable for the characterization of the species.

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Pachytene Chromosome Morphology inCoffeaL. I. Nucleolar Chromosomes

Cited by 17 publications

References 27 publications

Genetic diversity of a Coffea Germplasm Collection assessed by RAPD markers

Genetic diversity of a Coffea Germplasm Collection assessed by RAPD markers

Microcollinearity in an ethylene receptor coding gene region of the Coffea canephora genome is extensively conserved with Vitis vinifera and other distant dicotyledonous sequenced genomes

A Karyological Study in Some Species of Coffea L. and in the Closest Relative Psilanthus travancorensis (Wight & Arn.) J.-F. Leroy

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