Karyotype and NOR-banding of mitotic chromosomes of some Vitis L. species

Abstract

-Chromosome studies were performed in V. champinii, V. cinerea, V. girdiana, V. labrusca, V. rotundifolia, V. rupestris and V. vinifera with the purpose of species characterization using chromosome morphometric data and NOR banding. A median ideogram was obtained for each species. The karyotype formula obtained varied from 7m + 12sm to 9m + 11sm. The species showed moderate chromosome asymmetry values according to TF% form, Stebbins, Romero Zarco and Paszko indices. V. champinii and V. girdiana were apart from the other species by CVcl and CVci graphic representation and also formed a group apart in the dendrogram based on Euclidian distances. The chromosome pair number 3 harbors the secondary constriction and a satellite segment in all species analyzed with Giemsa staining and it may be the same observed after NOR banding technique. It seems that the process of speciation in the North American Euvitis species studied involved some discrete changes in chromosome morphometry which have been reflected in the asymmetry index. Index terms: karyotype, NOR-banding, mitotic chromosomes, Vitis, Vitaceae. ESTUDOS CROMOSSOMICOS DE ESPÉCIES DE Vitis RESUMO -Estudos cromossômicos foram efetuados em V. champinii, V. cinerea, V. girdiana, V. labrusca, V. rotundifolia, V. rupestris e V. vinifera com a finalidade de caracterização das espécies, usando dados de morfometria cromossômica e do bandamento NOR. Foi obtido um ideograma médio para cada espécie estudada. A fórmula cariotípica variou de 7m + 12sm a 9m + 11sm. As espécies mostraram assimetria cariotípica moderada pelos índices de TF% forma, Stebbins, Romero Zarco e Paszko. V. champinii e V. girdiana ficaram à parte das demais espécies pela representação gráfica de CVcl e CVci e também pelo dendrograma simplificado obtido pelo método de distância Euclidiana. O par cromossômico nº 3 apresentou constrição secundária e segmento satélite nas espécies analisadas com Giemsa, podendo ser o mesmo evidenciado pelo bandamento NOR. Parece que o processo de especiação das espécies de Euvitis americanas estudadas envolveu mudanças discretas na morfometria dos cromossomos a qual se refletiu no índice de assimetria cromossômica. Termos para indexação: cariótipo, bandamento NOR, cromossomos mitóticos, Vitis, Vitaceae.

Heat stress tolerance assayed in four wine-producing grapevine varieties using a cytogenetic approach

“…Nowadays, they can still be considered scarce when compared with other plant species. Most of the available cytogenetic studies performed in grapevine relied on the determination of the chromosome number in different Vitis species and V. vinifera varieties, karyotyping, physical location of ribosomal DNA loci and/or nucleolar organizer regions (NORs) positively stained with silver nitrate (Ag-NORs) or on the evaluation of the ribosomal RNA (rRNA) genes expression in different varieties and tissues (leaves and roots) (Haas et al, 1994;Haas and Alleweldt 2000;Pinto-Maglio et al, 2010;Pierozzi 2011;Pierozzi and Moura 2016;Castro et al, 2018). Other cytogenetic studies focused the meiotic behaviour of some grapevine varieties through the evaluation of pollen viability/ fertility and germination in natural and stressful conditions (Da Silva et al, 2001;Pereira et al, 2014).…”

Intrachromosomal karyotype asymmetry in Orchidaceae

“…The existing indexes are separated into two groups: interchromosomal asymmetry indexes, which quantify the heterogeneity in chromosome size, and intrachromosomal asymmetry indexes, which quantify the relative differences in the centromere position among chromosomes of a complement ( Stebbins, 1971 ; Peruzzi and Eroğlu, 2013 ). Among the interchromosomal asymmetry indexes, A 2 ( Romero-Zarco, 1986 ) and CV CL ( Paszko, 2006 ) are the most used due to their accuracy in the evaluation of chromosome dissimilarities ( Chiarini and Barboza, 2008 ; Souza et al , 2010 ; Pierozzi, 2011 ; Alves et al , 2011 ; Assis et al , 2013 ). However, there is no consensus about the best method for calculating the intrachromosomal asymmetry ( Romero-Zarco, 1986 ; Peruzzi and Eroğlu, 2013 ).…”

Karyotype Analysis in Grapevines

“…In the seven species studied chromosome 3 was the only one carrying a secondary constriction associated with a satellite segment on the long arm (Figures 2 and 3). Pierozzi (2011) observed only one pair of chromosomes with a terminal NOR band after silver impregnation in some grapes. However, it was not possible for the authors to discriminate which chromosome pair it was.…”

“…Loss of DNA segments in some species or gain of repeated DNA segments in others, as well as small structural rearrangements may also have occurred, as suggested by Pierozzi (2011). However, this remains an open question requiring further studies which may open possibilities and furbish some clues through a comparative analysis of the genome organization of the species.…”

“…Chromosome banding with specific fluorescent dyes in some Vitis species was first reported by Pinto-Maglio et al (2010) who observed a predominance of two pairs of chromosomes displaying positive CMA-bands. NOR banding was later applied to some Vitis species aimed at the obtainment of more detailed chromosome information (PIEROZZI, 2011). However, a media ideogram for each of the species studies with each chromosome individualized in the genome has yet been achieved or displayed.…”