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Dactylorhiza are hardy terrestrial orchids widespread across Asia and Europe, with some species now naturalized in North America. They grow in bogs, meadows and heathland in the temperate regions. Their distinguishing feature is the digitate or finger-like tubers, the generic name being derived from Greek dactylos (finger) and rhiza (root). Shakespeare referred to the orchid as ‘dead man’s fingers’ that were collected by witches. Renaissance physicians and naturalists called them Satyrion which many believed to be potent aphrodisiacs.

Interactions with mycorrhizal fungi have been increasingly recognized as one of the most important ecological factors determining the distribution and local abundance of orchids. While some orchid species may interact with a variety of fungal associates, others are more specific in their choice of mycorrhizal partners. Moreover, orchids that co-occur at a given site, often associate with different partners, possibly to avoid competition and to allow stable coexistence. However, whether differences in mycorrhizal partners directly affect seed germination and subsequent protocorm formation remains largely unknown. In this research, we used in vitro germination experiments to investigate to what extent seed germination and protocorm formation of Gymnadenia conopsea was affected by the origin and identity of fungal associates. Fungi were isolated from G. conopsea and three other co-occurring orchid species (Dactylorhiza viridis (Coeloglossum viride), Herminium monorchis, and Platanthera chlorantha). In total, eight fungal associates, belonging to Tulasnellaceae, Ceratobasidiaceae, and Serendipitaceae, were successfully isolated and cultured. While all eight fungal strains were able to promote early germination of G. conopsea seeds, only fungal strain GS2, a member of the Ceratobasidiaceae isolated from G. conopsea itself, was able to promote protocorm formation and subsequent growth to a seedling. Two other fungal strains isolated from G. conopsea only supported seed germination until the protocorm formation stage. The other five fungal strains isolated from the co-occurring orchid species did not support seed germination beyond the protocorm stage. We conclude that, although G. conopsea is considered a mycorrhizal generalist that associates with a wide range of fungi during its adult life, it requires specific fungi to promote protocorm formation and growth to a seedling. ispartof: MYCORRHIZA vol:30 issue:2-3 pages:221-228 ispartof: location:Germany status: published

espanolA partir de los resultados obtenidos de la extensa e intensa prospeccion del territorio, sepresenta informacion corologica sobre 9 taxones de la familia Orchidaceaeen la provinciade Segovia, Coeloglossum viride(L.) Hartm., Epipactis helleborine(L.) Crantz subsp. helle-borine, Epipactis microphylla(Ehrh.) Swartz., Epipactis tremolsii Pau, Ophrys fusca Link.subsp. fusca, Ophrys insectifera L. subsp. insectifera, Orchis papilionaceaL., Orchis ustulataL. y Spiranthes spiralis (L.) Chevall, asi como del hibrido Orchis x gennarii Reichenb. fil.(O. moriox O. papilionacea), los cuales ademas de constituir primeras citas provinciales,amplian notablemente el conocimiento de la orquidoflora silvestre de Segovia. Se aportandatos sobre su distribucion en la CCAA de Castilla y Leon, ecologia, estado de las pobla-ciones y conservacion. Asi mismo, se incluyen mapas de distribucion en cuadriculas UTMde 10x10 Km y material fotografico. EnglishBased on the results obtained from intense and extensive prospecting of the territory choro-logical information is hereafter put forward for 9 taxa from the Orchidaceaefamily in theprovince of Segovia, Coeloglossum viride(L.) Hartm., Epipactis helleborine(L.) Crantz subsp. helleborine, Epipactis microphylla(Ehrh.) Swartz., Epipactis tremolsii Pau, Ophrys fusca Link. subsp. fusca, Ophrys insectifera L. subsp. insectifera, Orchis papi-lionaceaL., Orchis ustulata L. and Spiranthes spiralis (L.) Chevall, as well as for the hybridOrchis x gennarii Reichenb. fil. (O. moriox O. papilionacea), which, besides representingthe first populations found in the province, noticeably increase the knowledge about thewild orchid flora in the province of Segovia. Data concerning their distribution, ecology,state of the populations and conservation in the Castilla y Leon region is brought forward.Also included is photographic material and distribution maps in 10x10 Km UTM grid cells. euskaraHango lurraldean egindako azterketa zabal eta sakonaren ondoren, Segoviako Orchidaceaefamiliako 9 taxoiren informazio korologikoa aurkezten da lan honetan. Coeloglossum viri-de(L.) Hartm., Epipactis helleborine(L.) Crantz subsp. helleborine, Epipactis microphylla(Ehrh.) Swartz., Epipactis tremolsii Pau, Ophrys fusca Link. subsp. fusca, Ophrys insectiferaL. subsp. insectifera, Orchis papilionaceaL., Orchis ustulata L. y Spiranthes spiralis (L.) Chevall, eta bai Orchis x gennarii Reichenb. fil. (O. moriox O. papilionacea) hibridoarenaere. Probintzian lehen zitak izateaz gain, Segoviako basa orkidofloraren ezagutza zabaltzeko urrats handia dira. Gaztela eta Leongo Autonomia Erkidegoan espezieek dutenbanaketaz, ekologiaz, populazioen egoeraz eta kontserbazioaz ere datuak aurkezten diralan honetan, baita 10 x 10 Km UTM kuadrikuletan banaketa mapak eta argazki-materialaere.

The digitate-tubered clade (Dactylorhiza s.l. plus Gymnadenia s.l.) within subtribe Orchidinae is an important element of the North-temperate orchid flora and has become a model system for studying the genetic and epigenetic consequences of organism-wide ploidy change. Here, we integrate morphological phylogenetics with Sanger sequencing of nrITS and the plastid region trnL-F in order to explore phylogenetic relationships and phenotypic character evolution within the clade. The resulting morphological phylogenies are strongly incongruent with the molecular phylogenies, instead reconstructing through parsimony the genus-level boundaries recognised by traditional 20th Century taxonomy. They raise fresh doubts concerning whether Pseudorchis is sister to Platanthera or to Dactylorhiza plus Gymnadenia. Constraining the morphological matrix to the topology derived from ITS sequences increased tree length by 20%, adding considerably to the already exceptional level of phenotypic homoplasy. Both molecular and morphological trees agree that D. viridis and D. iberica are the earliest-diverging species within Dactylorhiza (emphasising the redundancy of the former genus Coeloglossum). Morphology and ITS both suggest that the former genus Nigritella is nested within (and thus part of) Gymnadenia, the Pyrenean endemic 'N.' gabasiana apparently forming a molecular bridge between the two radically contrasting core phenotypes. Comparatively short subtending molecular branches plus widespread (though sporadic) hybridisation indicate that Dactylorhiza and Gymnadenia approximate the minimum level of molecular divergence acceptable in sister genera. They share similar tuber morphologies and base chromosome numbers, and both genera are unusually prone to polyploid speciation. Another prominent feature of multiple speciation events within Gymnadenia is floral paedomorphosis. The 'traditional' morphological and candidate-gene approaches to phylogeny reconstruction are critically appraised.

Two decades have passed since DNA evidence first demonstrated an intimate relationship between the circumboreal species 'Coeloglossum' viride and the temperate Eurasian genus Dactylorhiza s.s. Most subsequent molecular phylogenies showed 'C.' viride to diverge after the D. incarnata group. The law of monophyly therefore dictated inclusion in Dactylorhiza of 'C.' viride, irrespective of its undeniably distinctive morphology. Those orchid enthusiasts still determinedly seeking reasons for retaining the genus Coeloglossum have often used as a justification the one published molecular study that suggested that D. viridis diverged earlier than D. incarnata. Interestingly, these respective phylogenetic positions are supported by recent data-rich studies based on next-generation sequencing. However, recent DNA phylogenies also show that D. iberica — long regarded as morphologically distinct but nonetheless universally accepted as belonging within the genus — diverged penecontemporaneously with D. viridis. Thus, in order to justify maintaining 'Coeloglossum' as a separate monotypic genus it would also be necessary to transfer D. iberica to a new monotypic genus, thus recognising two genera that are not only monotypic but also show only modest molecular divergence from the remaining dactylorchids. Examining in greater detail the morphology and micromorphology of D. viridis and D. iberica, we show that both species possess multiple morphological character states that are unique within the genus Dactylorhiza, but argue that greater phenotypic disparity is commonly the case in early-divergent lineages per se. Review of previous publications discussing D. iberica revealed little knowledge of its autecology, and contradictory DNA-based inferences that can be traced back to just two original specimens. We also suggest that morphological and molecular variation within both species has been under-estimated and under-explored.

Different authors have demonstrated the usefulness of single-copy nuclear genes in unravelling the evolution of polyploid species' complexes. We used the chalcone synthase gene family to analyse relationships among several Dactylorhiza species belonging to the main diploid and tetraploid lineages of this genus and to evaluate relationships between Dactylorhiza and other orchid genera that traditionally have been considered to be closely related. Overall, 59 sequences from 19 taxa were analysed using parsimony and Bayesian inference. In our results, we recover a sister relationship between Dactylorhiza and Gymnadenia. In addition, our results support the idea that genera Coeloglossum and Dactylorhiza should be merged into one taxonomic entity. Finally, we add some information on the origin of allotetraploid Dactylorhiza taxa, such as D. praetermissa and D. elata. © 2010 The Linnean Society of London, Botanical Journal of the Linnean Society, 2010, 163, 155–165.

Glucosyloxybenzyl 2-isobutylmalates are one group of important active constituents in the tubers of Gymnadenia conopsea R. Br. and Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.). For the purpose of quality evaluation of these two Chinese herbal medicines, it is necessary to use a rapid and reliable assay that is suitable for the determination of their active constituents. A high-performance liquid chromatography method is firstly developed for the simultaneous quantification of five glucosyloxybenzyl 2-isobutylmalates in the tubers. The analytes including dactylorhin B, dactylorhin E, loroglossin, dactylorhin A, and militarine are isolated from the tubers of G. conopsea. The compounds are separated on an Agilent Hydrosphere C(18) (150 x 4.6 mm i.d., 5 microm) column using a mobile phase of acetonitrile-water including 0.3% acetic acid (adjusted with 36% acetic acid) with gradient elution at a flow rate of 1.0 mL/min. Detection is set at a UV wavelength of 221.5 nm. The recovery of the method is 97.7-101.0%, and linearity (r0.9998) is obtained for all the analytes. The assay is successfully applied to determine the contents of the analytes in the tubers of G. conopsea and C. viride var. bracteatum collected from different regions of China.

WOS: 000390711200007 A detailed micromorphological analysis of the labellum was carried out using both light and scanning electron microscopy on 14 genera (Anacamptis, Cephalanthera, Coeloglossum, Dactylorhiza, Gymnadenia, Himantoglossum, Limodorum, Neottia, Orchis, Ophrys, Platanthera, Serapias, Spiranthes, and Steveniella) of Orchidaceae in Turkey. In the samples, various epidermal features were identified in the spur that developmentally are invaginations of the labellum and the adaxial surface of the labellum. Typical secretory cells and inclusions such as starch or calcium oxalate crystals of different sizes and shapes were found within the structure of individuals. In many genera, characteristically shaped secretory trichomes and papillae were concentrated at the base part close to the gynostemium or the distal part of the labellum and on all surfaces of the spur. In the genus Ophrys, the labellum surface was covered with many hairs. Furthermore, the labellum surface striation varied among the orchid genera. UPGMA of cluster analysis was used to evaluate the morphological and micromorphological features of the labellum and spur among the analyzed taxa. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [114Z702] This work was supported by the Scientific and Technological Research Council of Turkey (TUBITAK, 2014), grant number 114Z702.

Previous phylogenetic analyses of Orchidaceae subtribe Orchidinae resulted in the proposal to classify Coeloglossum viride (L.) Hartman within the genus Dactylorhiza in order to maintain its monophyly. In this paper, we report some results that contradict previous studies regarding the monophyly of the traditional Dactylorhiza and its phylogenetic relationship with Coeloglossum. Our results, which combine sequences of the internal and external transcribed spacers of the nuclear ribosomal DNA, support the monophyly of Dactylorhiza, with Coeloglossum being a sister clade. The position of C. viride in the phylogenetic tree, and the considerable morphological differences with respect to Dactylorhiza, incline us to retain both lineages as distinct genera.

Seven new compounds, named coelovirins A-G (1-7), along with fourteen known constituents were isolated from the rhizomes of Coeloglossom viride var. bracteatum (Orchidaceae). On the basis of chemical and spectroscopic methods, including 2D-NMR techniques, the structures of new compounds were elucidated as 1-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-isobutyltartrate (1), 4-(4-beta-glucopyranosyloxybenzyl)-(2R,3S)-2-isobutyltartrate (2), 1-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartrate (3), 4-(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartrate (4), (2R,3S)-2-beta-D-glucopyranosyl-2-isobutyltartaric acid (5), bis(4-beta-D-glucopyranosyloxybenzyl)-(2R,3S)-2-[beta-D-glucopyranosyl-(1 --> 4)-beta-D-glucopyranosyl]-2-isobutyltartrate (6) and bis(4-beta-D-glucopyranosyloxybenzyl)-(2R)-2-[beta-D-glucopyranosyl-(1 --> 4)-beta-D-glucopyranosyl]-2-isobutylmalate (7). The known compounds are 4-hydroxybenzaldehyde, 4-hydroxybenzyl alcohol, 4,4'-dihydroxydibenzyl ether, 4,4'-dihydroxydiphenylmethane, 4-(4-hydroxybenzyloxy)benzyl alcohol, gastrodin, quercetin-3,7-diglucoside, thymidine, loroglossin, militarine, dactylorhin A, dactylorhin B, beta-sitosterol and daucosterol.

Seeds of 21 taxa of the genera Dactylorhiza (incl. Coeloglossum), Gymnadenia (incl. Nigritella) and Pseudorchis were examined by light microscope and SEM. Qualitative and quantitative characters were analyzed. In Dactylorhiza, the seeds are fusiform, but some populations of D. viridis show clavate seeds. According to the ornamentation of the periclinal walls, 3 types of seeds are recognized in this genus. The considerable variation in the seed coat ornamentation pattern in the taxa belonging to majalis, maculata, and praetermissa groups of the genus Dactylorhiza is congruent with the genetic processes that occurred during the history of this genus. Gymnadenia shows clavate seeds with stout and straight to slightly curved anticlinal walls, although these are straight to wavy in some taxa considered previously as Nigritella. These taxa also show low values of seed length. Pseudorchis has fusiform seeds without ornamentation in the periclinal walls and fine anticlinal walls. Our study supports the inclusion of the former genus Coeloglossum in Dactylorhiza.

Coeloglossum viride(L.) Hartm. has a worldwide distribution in the Northern hemisphere where it can be found in a broad range of habitats; it is not, at present, threatened with extinction. However, in several European countries there has been a dramatic decline in sites occupied by this orchid. In The Netherlands only 2 populations remain of 55 extant before 1950. Knowledge of its ecology and life history are necessary to preserve this species at sites not directly threatened by habitat destruction. The results of a 7 year demographic study of a population ofC. viridein The Netherlands are presented. Annual recruitment and mortality vary considerably from year to year, whereas the flux in individual plants is always high. The half-life of the cohorts varies from 1.0 to 2.4 years and is on averagec. 1.5 years. This indicates thatC. virideis a short-lived terrestrial orchid species. The number of flowers per inflorescence varies from 2 to 26 per spike. The mean flowering percentage in the population is rather high (50%), while the fruit production was low in the year this was recorded (1994),viz. c. 10%. The average number of seeds per capsule wasc. 2300. Plants emerging above ground for the first time are already able to produce an inflorescence, and the average number of flowers equals those of plants initially passing a vegetative life phase for one or more years. Dormancy is a rare phenomenon in this species and the absence above ground when it does occur does not last longer than one growing season. Vegetative multiplication plays a minor role in population dynamics. The studied population is likely to be in a healthy state: there is a high recruitment almost every year resulting in a vigorous age structure. Management of the site, with mowing in July following seed dispersal and sheep grazing in winter is beneficial. The absence of intentional fertilization is a condition for a suitable, low vegetational structure of the sward during the growing season of this species.

The seasonal development and mycorrhizal fungi of the mycorrhizae of Platanthera hyperborea, Platanthera obtusata, Platanthera orbiculata, and Coeloglossum viride are described. Fungal endophytes belonging to the following taxa were identified: Leptodontidium orchidicola, Epulorhiza repens, Epulorhiza anaticula comb, nov., and Ceratorhiza goodyerae-repentis. In addition, anamorphic material of a species tentatively identified as Sebacina sp. was found solely in the mycorrhizae of P. orbiculata. A series of isolates bearing distinctive, clamped monilioid cells and belonging to an unidentified species of Sistotrema was found in P. obtusata. This is the first report of a Sistotrema species from orchid mycorrhizae. An isolate from C. viride, with broad hyphae, large globose monilioid cells, and dark brown mycelium, resembles Burgeff's 1936 description of Rhizoctonia anomala nom.inval. This taxon is validated, redescribed, and presented as the new species Moniliopsis anomala.

Coeloglossum Hartm. Hohlzunge, Published as part of Elias Landolt, 2001, Orchidaceae, pp. 232-258 in Flora des Sihltals von der Stadt Zürich bis zum Höhronen, Basel :Fachstelle Naturschutz Kanton Zürich on page 246, DOI: 10.5281/zenodo.248047

483. Coeloglossum viride (L.) Hartm. Hohlzunge Blüte. Gelbgrün. 5-6. Standort. Montan bis alpin. Kalkfreie Böden. Trockene Riedwiesen, Borstgrasrasen. Literatur. Eo: Hinter Mistlibüel; Salen; Weberrüti; Itlimoos; Langmoos, Hütten, Sihlhalden, Hütten; Dürrenrmooshalde. - Me: Zerstreut in der oberen montanen und subalpinen Stufe. Gottschalkenberg: Salen; Südhang Raten. Sihltal (ZH): Langmoos und Sihlhalde. Herbar. RIc: Samstagern, Weberrüti (1924; Standort 1940 durch Melioration vernichtet). Verbreitung. Selten (nur 2 Fundstellen). OAe: Chäsgaden, 1080 m, 693.18/223.12 (ca. 20 Ex., 2007). RIc: Samstagern, Stollenrain, 694.80/227.55 (> 10 blühende Ex., R. Irniger 2005). U: 2, H: 1/1, E: 4, W: I. - Eurasien, Nordamerika. Veränderungen.>/>/>. - g. - Gefährdung. CR/-/RE/LC. Verbreitungsmuster. -., Published as part of Elias Landolt, 2001, Orchidaceae, pp. 232-258 in Flora des Sihltals von der Stadt Zürich bis zum Höhronen, Basel :Fachstelle Naturschutz Kanton Zürich on pages 246-247, DOI: 10.5281/zenodo.248047

The orchid genera Dactylorhiza and Coeloglossum are among the most widely distributed of all north temperate orchid genera, both being reported from Europe, Asia as far south as the Himalayas and in northern North America, e.g., Moore & So6 (in Tutin & al., Flora Europaea 5: 335-337. 1980), Stace (New Flora of the British Isles ed. 2: 973-979. 1997), Renz & Taubenheim (in Davis, Flora of Turkey 8: 450-599. 1984), Renz (in Rechinger, Flora Iranica 126: 58-139. 1978), and Luer (Native Orchids of the United States and Canada: 154-160, 170-174. 1975). Dactylorhiza species are numerous and prominent and distinctive elements of the vegetation, especially of lowland and montane marshes and meadows; the solitary species of Coeloglossum is rather inconspicuous and found in grassland and on the edges of woods in both lowland and montane habitats. Using molecular and morphological data, recent cladistic analyses of European members of the tribe Orchidoideae (Orchidaceae) by Pridgeon & al. (in Lindleyana 12: 89-109. 1997), Bateman & al. (in Lindleyana 12: 113-141. 1997), and Pridgeon & al. (Genera Orchidacearum 2: 2001) have demonstrated that Coeloglossum nests within the much larger genus Dactylorhiza. In habit, Coeloglossum viride (L.) Hartm. falls within the range of variation of Dactylorhiza but its flowers are green or brown and lack a spur. It interbreeds freely with Dactylorhiza species in the wild and numerous natural hybrids between them have been described. Bateman & al. (l.c.) and Pridgeon & al. (l.c., 2001) consider that they are congeneric and use the name Dactylorhiza for the combined genus. Coeloglossum, however, is the earlier generic name, having been published by Hartmann (Handb. Skand. Fl. ed. 1: 329. 1820) based upon Satyrium viride of Linnaeus (Sp. PI.: 944. 1753) while Dactylorhiza, although coined by Necker in Elementa Botanica iii: 129 (1790), a suppressed work for publication of generic names (Art. 32.7 and App. V), was first validated by Nevski (in Acta Inst. Bot. Acad. Sci URSS. ser. 1, fasc. 4. 1937). Dactylorhiza was lectotypified by Orchis umbrosus Kar. & Kir. (D. umbrosa (Kar. & Kir.) Nevski) by So6 (Orchidee (Hamburg) 19: Sonderheft 19. 1968). The rule of priority in the International Code

Pure cultures of endophytic fungi were obtained from the mycorrhizae of some native Alberta orchids (Amerorchis rotundifolia, Calypso bulbosa, Coeloglossum viride, Corallorhiza maculata, Platanthera dilatata, P. hyperborea, P. obtusata). Isolates of Rhizoctonia constituted the largest group of endophytes, but few could be identified to species. One of these strains was identified as Rhizoctonia repens, a species reported to be a ubiquitous and common mycorrhizal fungus of orchids. Another strain produced the teleomorph stage and was identified as Ceratobasidium obscurum. Rhizoctonia anaticula Currah, sp.nov. is described based on five isolates bearing monilioid cells linked by prominent, narrow connections. A second group of isolates consisted of sterile, greenish black to grey fungi. After prolonged incubation, eight of these isolates formed conidia. Two isolates produced phialoconidia and were identified as Phialocephala fortinii. Five isolates, demonstrating sympodial development of conidia in the apical region of swollen or unswollen hyaline conidiogenous cells, are disposed in Leptodontidium orchidicola Sigler & Currah, sp.nov. The remaining conidial isolate was identified as Trichocladium opacum. Two isolates, resembling Rhizoctonia in cultural features, sporulated and are described as Trichosporiella multisporum Sigler & Currah, sp.nov.

OBSERVATIONS ON THE CARYOLOGY OF GENNARIA DIPHYLLA (LINK) PARL. (COELOGLOSSUM DIPHYLLUM FIORI) — Some caryological characters of Gennaria diphylla (Link) Parl, have been here investigated. Chromosome counts from somatic metaphases show a 34 chromosomes diploid set; the resting nuclei have been classified as half-reticulated with chromocenters (« noyaux semi-reticule a chromocentres » according to Delay's classification); in prophases we have noticed that chromocenters often appear like prochromosomes. The chromosome number 17 (2n = 34) is new for the Ophrydinae. The interest of this research lies in the fact that the species here dealt with has been differently classified by various Authors.

Summary Symbiosis tests carried out between orchids from several geographical localities and thirty-two Rhizoctonias isolated from orchids, non-orchid hosts and soils of worldwide distribution, showed no evidence of any species-to-species relationship between orchid and fungus. Dactylorhiza purpurella established a symbiotic relationship with most fungi tested while Coeloglossum wide, Goodyera repens and Cymbidium canaliculatum, although less frequently symbiotic, established compatible infections with many isolates. Among orchids with photo-synthetic protocorms, Epidendrum radicans was compatible with several fungi but three other species of Epidendrum together with Spathoglottis plicata and a Laeliocattleya cultivar were symbiotic only with Tulasnella calospora and certain Ceratobasidium isolates. Tulasnella calospora may be a universal orchid symbiont. Ceratobasidium cornigerum and Thanatephorus orchidicola commonly occur as root endophytes but are doubtfully symbiotic with most orchids. T. cucumeris is frequently symbiotic with Dactylorhiza purpurella but less commonly so with other orchids tested.

Summary Extensive isolation of root endophytes from Orchis (Daciylorchis) purpurella and other British orchids yielded a variety of strains of Rhizoctonia and of other fungi. R. repens, a common orchid endophyte, occurred in several host species and habitats. R. solani was uncommon, being obtained only from Orchis purpurella and Coeloglossum viride in certain situations. Most Rhizoctonia strains were obtained from only one plant and one habitat and the evidence indicated that there was no specificity between host and endophyte. In symbiosis tests isolates from roots generally infected the protocorms but did not always stimulate the growth of the species from which they originated. Four strains of R. solani isolated from soil were stimulatory to Orchis purpurella protocorms. Of four Rhizoctonia solani strains pathogenic on crop hosts, two stimulated protocorm growth and one was parasitic. It is suggested that the occurrence of a strain as a root endophyte may largely be a reflection of its distribution and of the factors affecting its growth in the soil.

Summary Concentrations (w/v) of 1–10 ppm kinetin, with or without 1 ppm indoleacetic acid, may retard the germination of Dactylorhiza (Orchis) purpurella seed but increase the rate of growth of protocorms to the point where shoot initials form. Subsequently diurnal illumination enhances the development of the shoot initial. Chlorophyll production is independent of growth factors and occurs most rapidly at temperatures below 15°C. Green shoot-initials undergo further development only after prolonged cold treatment and this stage appear to be independent of growth factors or symbiotic fungi. Similar results were obtained with Coeloglossum viride and Platanthera bifolia. Goodyera repens, an evergreen rhizomatous species, did not respond to mixtures of kinetin and indoleacetic acid, or coconut milk, but grew well on potato or yeast extracts, or after infection with symbiotic fungi. Symbiotic development of north temperate orchids occurs on defined media lacking growth factors and is always more rapid than that in any axenic system so far tested.