Eight species of Ophrys sect. Pseudophrys (Orchidaceae) were cytogenetically studied. The analysed species possess the most symmetrical karyotypes of the genus (MCA ranged from 10.21 to 15.87 and CVCL from 19.61 to 23.93) with 2n = 2x = 36, being composed of mainly metacentric chromosomes. The karyotype formulae were: 36m for Ophrys archimedea, 32m + 4sm for O. flammeola, 32m + 4sm for O. funerea, 36m for O. laurensis, 36m for O. lojaconoi, 34m + 2sm for O. lucifera, 34m + 2sm for O. obaesa and 36m for O. pallida. Karyotype morphometric characters were evaluated by calculating MCA and CVCL for the assessment of karyotype asymmetry, and CVCI for the evaluation of heterogeneity in the position of the centromeres. The relationships between species were thus finally elucidated. The species characterised by wide distribution show greater karyomorphological distance than those with restricted distribution. The possible evolutionary role of chromosomal rearrangements as well as gene mutations in the speciation of Ophrys is discussed.
New cytological data in Ophrys sect. Pseudophrys Godfery and comparative karyomorphological studies in Ophrys L. (Orchidaceae)
Turco A.
;Albano A.;Medagli P.;
2018-01-01
Abstract
Eight species of Ophrys sect. Pseudophrys (Orchidaceae) were cytogenetically studied. The analysed species possess the most symmetrical karyotypes of the genus (MCA ranged from 10.21 to 15.87 and CVCL from 19.61 to 23.93) with 2n = 2x = 36, being composed of mainly metacentric chromosomes. The karyotype formulae were: 36m for Ophrys archimedea, 32m + 4sm for O. flammeola, 32m + 4sm for O. funerea, 36m for O. laurensis, 36m for O. lojaconoi, 34m + 2sm for O. lucifera, 34m + 2sm for O. obaesa and 36m for O. pallida. Karyotype morphometric characters were evaluated by calculating MCA and CVCL for the assessment of karyotype asymmetry, and CVCI for the evaluation of heterogeneity in the position of the centromeres. The relationships between species were thus finally elucidated. The species characterised by wide distribution show greater karyomorphological distance than those with restricted distribution. The possible evolutionary role of chromosomal rearrangements as well as gene mutations in the speciation of Ophrys is discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
