Ophrys Species Research Articles

La pollinisation de l’Ophrys arachnitiformis (Orchidaceae) par les mâles de Colletes cunicularius (L.) (Hymenoptera, Colletidae) dans les Pyrénées Atlantiques.

Pollination of Ophrys arachnitiformis (Orchidaceae) by males of Colletes cunicularius (L.) (Hymenoptera, Colletidae) in the Atlantic Pyrenees. The pollination of Ophrys arachnitiformis (Orchidaceae) by patrolling males of the solitary bee Colletes cunicularius (Hymenoptera, Colletidae) was investigated in spring 2006 in southern France. Our observations provide evidence that C. cunicularius males pollinate the flowers of O. arachnitiformis in both “cephalic” and “abdominal” positions, which challenges previous records on the constancy of the position of the pollinator on the Ophrys flowers during “pseudocopulations”. Furthermore, these observations may account for the occasional formation of hybrids between sympatric Ophrys species sharing a pollinator but for which the position of the insect on the flowers differs during pseudocopulations.

Pollinator attracting odour signals in sexually deceptive orchids of the Ophrys fusca group

We investigated patterns of volatiles of several allopatric and sympatric species of the Ophrys fusca group and one species of the O. mammosa/sphegodes group pollinated by either Andrena nigroaenea or A. flavipes, using electrophysiology (gas chromatography coupled with electroantennography; GC-EAD) and chemical analyses. We found 52 GC-EAD active compounds, mainly saturated and unsaturated hydrocarbons with chain lengths of 21 to 31, aldehydes, an ester, and an acid. Based on the relative proportions of all GC-EAD active compounds, the investigated species were compared using various statistical methods (ANOVA, principle component analyses, discriminant function analyses and cluster analyses). Our results show that Ophrys species with the same pollinator – independent of their phylogenetic relationship–use the same volatiles for pollinator attraction. Differences between the species mainly involve different quantitative patterns of volatiles. Our results are in congruence with previous studies that showed different odour bouquets to be responsible for the specific attraction of different pollinators and that alkanes and alkenes are most important for pollinator attraction.

Karyomorphology, heterochromatin patterns and evolution in the genus Ophrys (Orchidaceae)

Karyotype structures and heterochromatin distribution in representative taxa of the genus Ophrys are compared, based on Feulgen-stained and banded somatic metaphase chromosomes. The karyotypes of Ophrys iricolor, O. lupercalis, O. caesiella, O. lutea, O. lunulata, O. x. tardans, O. apifera, O. praecox, O. lacaitae and O. insectifera are described for the first time. The karyological analyses indicate the relationships among the species with respect to asymmetry indices and heterochromatin content. Chromosomal differences have been helpful in clarifying the taxonomic position of Ophrys species that do not have clear affinities. The representative species of Araniferae, Fuciflorae and Ophrys sections exhibited the most asymmetrical karyotypes, while chromosome complements of the O. fusca–O. lutea group, of O. tenthredinifera and of O. bombyliflora proved to be less asymmetrical. Weakly heterochromatic chromosomes, with heterochromatin present mostly in thin centromeric bands, characterize Ophrys C-banded karyotypes. Chromomycin A3 (CMA) staining revealed that the analysed species exhibit a weak pattern of CMA+ bands at centromeric, intercalary or telomeric regions. No DAPI bright blocks were observed. The significance of the karyological data is discussed with regard to the relationships between the analysed species. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 148, 87–99.

In vitro germination, protocorm formation and plantlet development of mature versus immature seeds from several Ophrys species (Orchidaceae)

We investigated the effect of genotype, seed maturity and culture medium on the in vitro germination and development of protocorms and plantlets from seeds of 13 different Ophrys species (O. apifera, O. attica, O. cornuta, O. delfinensis, O. ferrum-equinum, O. lutea, O. mammosa, O. speculum, O. spruneri, O. umbilicata, O. argolica, O. irricolor and O. tenthredinifera) collected in Greece, some of which are endemic to this country. Mature seeds (10 months after collection) and immature seeds (2 months after anthesis) were cultured in a coconut milk-enriched or a pineapple-enriched medium (CEM or PEM, respectively). The highest percentage of callogenesis (96%) was observed in immature seeds of O. delphinensis in the CEM, while the highest percentage of protocorm formation (52%) was observed in mature seeds of O. spuneri in the CEM. Protocorm formation was significantly lower in immature seeds than in mature seeds in both culture media. Eventually almost all of the transferred protocorms developed to plantlets, which later formed minitubers. PEM appeared to be the most suitable for the development of minitubers from plantlets. All of the factors investigated--as well as their interactions--significantly affected callogenesis and protocorm formation. The results are discussed with the perspective of applying an improved protocol for in vitro seed germination and plantlet formation in several under-utilized Ophrys species.

Karyological and taxonomic notes on Ophrys (Orchidoideae, Orchidaceae) from the Iberian Peninsula

Karyological information on Iberian Ophrys species is very limited. This paper provides the haploid and diploid chromosome numbers of 11 taxa of sect. Pseudophrys and sect. Ophrys, both of which are well represented in the Iberian Peninsula, and two taxa from Tunisia. The first data on chromosome numbers for O. vasconica (2n = 72, 74), O. ficalhoana (2n = 36), O. picta (2n = 36), O. sphegifera (n = 18, 2n = 36, 38) and O. passionis (2n = 36) are also presented, confirming the stability of the chromosome number in Ophrys. In addition, populations of the group O. omegaifera (O. dyris and O. vasconica), together with tetraploidy, pentaploidy and the existence of aneuploid phenomena, are reported for the first time in Iberia. The basic diploid number is always 2n = 36. The karyotypes of several species were analysed. Evolutionary trends in Ophrys chromosomes are discussed. Taxonomic and phytogeographical details are provided on several species or groups of species from Iberia.

GENE FLOW ACROSS SPECIES BOUNDARIES IN SYMPATRIC, SEXUALLY DECEPTIVE OPHRYS (ORCHIDACEAE) SPECIES

Orchids of the genus Ophrys (Orchidaceae) are pollinated by male bees and wasps through sexual deception. The Ophrys sphegodes group encompasses several closely related species that differ slightly in floral morphology and are pollinated by different solitary bee species. Populations representing different species of the O. sphegodes group often flower simultaneously in sympatry. To test whether gene flow across the species boundaries occurs in these sympatric populations, or whether they are reproductively isolated, we examined the distribution of genetic variation within and among populations and species of this group. We collected at each of five different localities in southern France and Italy two sympatric, co-flowering Ophrys populations, representing six Ophrys species in total. The six microsatellite loci surveyed were highly variable. Genetic differentiation among geographically distant populations of the same species was lower than differentiation among sympatric populations of different species. However, the strength of genetic differentiation among species was among the lowest reported for orchids. Genotype assignment tests and marker-based estimates of gene flow revealed that gene flow across species boundaries occurred and may account for the low observed differentiation among species. These results suggest that sexual deceit pollination in Ophrys may be less specific than thought, or that rare mistakes occur.

Hybriden und hybridogene Sippen ausOphrys bertolonii undO. atrata (Orchidaceae)

Flower polymorphism in 15 ItalianOphrys populations (N = 282) was analysed in detail. Statistical and graphical evaluation of data demonstrates morphological relationships and amount of hybrid character coherence.O. bertolonii s. str. andO. atrata are stable parental taxa, but occasionally form hybrids and hybrid swarms. Much evidence suggests that it was through such homogamic hybridization, involving these and other species ofOphrys, that the stabilized taxaO. bertoloniiformis andO. promontorii (ecologically different, but sympatric with the parents on Gargano), andO. benacensis (geographically separated from the parents in the Insubric region) originated. These differentiation-hybridization cycles are linked to the break-down and new establishment of incomplete prezygotic crossing barriers (e.g. different flower biology, flowering time, habitat preference).

Population Variability, Hybridization, and Introgression in Some Species of Ophrys

Population Variability, Hybridization, and Introgression in Some Species of Ophrys

POPULATION VARIABILITY, HYBRIDIZATION, AND ***INTROGRESSION IN SOME SPECIES OFOPHRYS

EvolutionVolume 10, Issue 1 p. 32-46 ArticleFree Access POPULATION VARIABILITY, HYBRIDIZATION, AND ***INTROGRESSION IN SOME SPECIES OF OPHRYS G. Ledyard Stebbins, G. Ledyard Stebbins Department of Genetics, University of California, Davis, Stazione Sperimentale di Maiscoltura, Bergamo, ItalySearch for more papers by this authorL. Ferlan, L. Ferlan Department of Genetics, University of California, Davis, Stazione Sperimentale di Maiscoltura, Bergamo, ItalySearch for more papers by this author G. Ledyard Stebbins, G. Ledyard Stebbins Department of Genetics, University of California, Davis, Stazione Sperimentale di Maiscoltura, Bergamo, ItalySearch for more papers by this authorL. Ferlan, L. Ferlan Department of Genetics, University of California, Davis, Stazione Sperimentale di Maiscoltura, Bergamo, ItalySearch for more papers by this author First published: March 1956 https://doi.org/10.1111/j.1558-5646.1956.tb02827.xCitations: 16AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume10, Issue1March 1956Pages 32-46 ReferencesRelatedInformation

The Fertilisation of Orchids

WHILE botanising this spring in Portugal, I was struck with the fact that scarcely one of the orchids—species of Ophrys principally—that I had collected for my herbarium, or examined in the field, seemed to be fertilised, for none presented the least indication of having had pollen applied to its stigmatic surface; and I examined flowers in every stage of expansion, from the opening of the bud to the withered and shrunk up floral envelopes. Each one, I remarked besides, contained its own pollinia, their caudicles in their respective glands and in their natural position. I was so struck with this, that one day (March 31) I gathered and examined forty-five different flower-heads, and of all these only one was found to have pollen-grains on its stigma, and all, the fertilised one included, had their pollinia intact. The locality was the Tapada d'Ajuda, or Royal Park, situated just outside the city walls of Lisbon, an inclosure containing many acres of land, clothed in spring with a rich flora, and a favourite entomological hunting ground, teeming with Coleoptera, Hymenoptera, and the commoner Lepidoptera. Several of the orchids contained aphides, and a few harboured a species of small red ant.