Sexual Compatibility Research Articles

GENE FLOW IN SECTION Batatas (CONVOLVULACEAE).

It is well known that crossability within section Batatas is a complex phenomenon because of genetic, cytogenetic and physiological implications. During 1988 to 1991 we investigated the factors involved in crossability. In the 1st stage, self-compatibility was determined/verified in I. cynanchifolia (2x), I. grandifolia (2x), I. triloba (2x), I. x leucantha (2x), I. lacunosa (2x), I. tenuissima (2x), I. ramosissima (2x) and I. cordato-triloba (2x). Additionally, self-incompatibility was verified in I. trifida (2x), I. tiliacea (4x) and I. batatas (4x,6x). It is postulated that sexual compatibility is related to a multiallelic sporophytic incompatibility system. In the second stage, 4,162 cross pollinations between 11 species were performed at La Molina and San Ramon, and 76 interspecific combinations from 110 possible theoretic combinations in a diallelic 11 × 11 design were obtained. Of 76 interspecific combinations, 38 succeded with a crossability rate ranging from 0.01 to 1.00 at La Molina. In San Ramon, of 17 interspecific combinations, 11 were succesfull when estimating crossability from 0.01 to 0.71. Considering the factors affecting crossability, it was found that latitude influences flowering synchrony in progenitors, and in the germination process, and the early death of seedlings is related to an unbalanced genome (embryo/endosperm) relationship. In interspecific crosses, it was shown that I. trifida and I. x leucantha act as “bridge species”.

Orgasm consistency training in the treatment of women reporting hypoactive sexual desire: An outcome comparison of women-only groups and couples-only groups

To evaluate and compare the effectiveness and maintenance of two group interventions using orgasm consistency training in the treatment of female hypoactive sexual desire, 57 women were randomly assigned to a women-only group, a couples-only group, or a waiting list control group. Controlling for social desirability, subjects were assessed on six variables: sexual compatibility, sexual esteem, sexual desire, sexual fantasy, sexual assertiveness, and sexual satisfaction. Independent assessments were made on these variables before treatment, after treatment, and at 6 months follow-up. Although the treatment was found to be generally effective in women reporting hypoactive sexual desire, a consistent pattern of change favoring the couples-only group was evident on all measures. Possible explanations for the superiority of couples-only interventions are explored in the discussion.

Yeasts Isolated from Homobasidiomycetes ( Asterophora, Collybia): New Aspects for Sexuality, Taxonomy, and Speciation

Prillinger, H., Altenbuchner, J., Laaser, G., and Dörfler, C. 1993. Yeasts isolated from Homobasidiomycetes ( Asterophora, Collybia): New aspects for sexuality, taxonomy, and speciation. Experimental Mycology 17, 24-45. A positive selection vector to clone fungal nDNA in Escherichia coli together with random-fragment hybridization analysis turned out to be useful for clarifying the taxonomic relationship between the yeast and hyphal strains from Asterophora lycoperdoides and A. parasitica, on the one hand, and for confirming conspecificity of the Collybia yeasts ( C. cirrata, C. cf. cookei, and C. tuberosa) and detecting processes of speciation, on the other. The rapid loss of sexual compatibility between the yeast and hyphal strains from Collybia accompanied by a distinct RFLP with a few nDNA probes permits the early stages of speciation in the dimorphic Collybia species to be investigated. Although the species-specific intracellular yeasts isolated from two Asterophora species exhibited a remarkable degree of nDNA/nDNA reassociation and an identical ubiquinone (Q-9) system, conspecificity as well as a suspected partial identity of the nDNA from Asterophora yeasts and hyphae could be excluded. The conspecificity of the Collybia yeasts and hyphae, already established by morphological data and rDNA analysis, could be confirmed using homologous and heterologous hybridization experiments performed with Southern-blotted nDNA digested with different restriction endonucleases and hybridized with cloned 3- to 10-kb BamHI nDNA fragments from yeasts and hyphae as a probe. The physiological characterization of the Collybia yeasts displayed a remarkable variability. The qualitative and quantitative monosaccharide pattern of purified yeast cell walls exhibited some similarities to tremelloid fungi. Data are discussed in the light of taxonomy, mating-type evolution, and speciation.

Isolation of Glomerella musae [teleomorph of Colletotrichum musae (Berk. & Curt.) Arx.] and segregation analysis of ascospore progeny

The sexual stage of Colletotrichum musae has been obtained under controlled laboratory conditions. Development of the sexual stage required light and suboptimal growth temperature. Meiosis was apparent as judged by the formation of perithecia typical of ascomycetes classified as Glomerella. Perithecia contained as many as 50–80 asci, each of which contained up to eight ascospores. The ascospores were larger than conidia and were easily dissected for segregation analysis of either random spores or tetrads. In order to determine if this meiotic system was homothallic or heterothallic, chlorate-resistant mutants were isolated and crossed with wild type. Chlorate resistance and susceptibility segregated in a 1:1 ratio, indicating that this system was heterothallic. Sexual recombination was observed by analyzing the segregation of several DNA markers identified by amplification of polymorphic fragments of genomic DNA using single oligonucleotide primers and Taq DNA polymerase. Segregation consistent with mendelian inheritance and sexual recombination of genetic markers indicated that it is feasible to construct a genetic map for this species. The complexity of sexual compatibility was analyzed by crossing several ascospore progeny which identified four distinct mating types.

Fungal mating type genes — regulators of sexual development

The mating type genes of the fungi determine sexual compatibility between different haploid individuals. In both ascomycetes and basidiomycetes the genes are seen to influence directly or indirectly the expression of developmentally regulated genes. Mating type genes from several species have now been cloned and sequenced and alternative forms within the same species are generally found to be unrelated or very dissimilar in sequence. In most cases the genes encode proteins with characteristic DNA binding motifs (transcription factors). In the yeast, Saccharomyces cerevisiae , sequence-specific DNA binding of purified proteins has been demonstrated and involves different protein associations in different cell types. Evidence for similar protein-protein interactions between mating type encoded transcription factors exists for basidiomycetes but has yet to be demonstrated in other ascomycete fungi. It is interesting to find that the genes for mating pheromones that are subject to regulation by mating type proteins in ascomycete fungi are encoded directly by mating type genes in basidiomycetous yeasts.

Sexual motivation, patriarchy and compatibility

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Interbreeding Populations of SomeMarasmiusSpecies

Intercollection crosses of four Marasmius species were analyzed to assess the geographic extent of sexual compatibility and to reveal probable complexity of mating type loci. Marasmius pulcherripes, M. pyrrhocephalus and M. rotula showed universal compatibility between intracontinental conmorphospecific collections. Available intercontinental data on M. siccus suggested that infraspecific sexual barriers may be present.

Panellus Stypticus: Geographically Separated Interbreeding Populations

Utilizing matings of single-spore isolates of collections of Panellus stypticus from far eastern USSR, New Zealand, Japan and eastern North America, the geographic range of interbreeding populations was ascertained to include all these locations. Culture bioluminescence and basidiome taste differed across this range, apparently independent of sexual compatibility.

Preliminary Analysis of Genetic Complementation of Bioluminescence inPanellus StypticusIsolated from Pine and Hardwood

Inheritance of bioluminescence in North American populations of Panellus stypticus was analyzed using a set of five nonbioluminescent monokaryons and one bioluminescent monokaryon obtained from a basidiocarp of P. stypticus collected on pine wood. These were crossed with two nonbioluminescent and two bioluminescent monokaryons obtained from basidiocarps collected on hardwood in four geographically separate locations. Sexual compatibility of the geographically separate isolates indicated they were of the same biological species. Changing levels of bioluminescence intensities over time in the resulting dikaryotic cultures indicated that bioluminescence may be under stage-specific regulation. Inheritance of bioluminescence was analyzed according to the actual versus the expected maximal levels of bioluminescence intensity in dikaryons having at least one bioluminescent monokaryotic component. Bioluminescence was a dominant feature among the isolates tested. Genetic complementation groups established for dikaryons with two nonbioluminescent monokaryotic components suggested that three separate naturally occurring mutations can lead to lack of bioluminescence. Inter-allelic complementation may be involved in the expression of bioluminescence in a dikaryon resulting from a cross of two nonbioluminescent monokaryons. No significant differences among dikaryons were found in the characterization of bioluminescence emission spectra regardless of monokaryon composition.

Preliminary Analysis of Genetic Complementation of Bioluminescence in Panellus stypticus Isolated from Pine and Hardwood

Inheritance of bioluminescence in North American populations of Panellus stypticus was analyzed using a set of five nonbioluminescent monokaryons and one bioluminescent monokaryon obtained from a basidiocarp of P. stypticus collected on pine wood. These were crossed with two nonbioluminescent and two bioluminescent monokaryons obtained from basidiocarps collected on hardwood in four geographically separate locations. Sexual compatibility of the geographically separate isolates indicated they were of the same biological species. Changing levels of bioluminescence intensities over time in the resulting dikaryotic cultures indicated that bioluminescence may be under stage-specific regulation. Inheritance of bioluminescence was analyzed according to the actual versus the expected maximal levels of bioluminescence intensity in dikaryons having at least one bioluminescent monokaryotic component. Bioluminescence was a dominant feature among the isolates tested. Genetic complementation groups established for dikaryons with two nonbioluminescent monokaryotic components suggested that three separate naturally occurring mutations can lead to lack of bioluminescence. Inter-allelic complementation may be involved in the expression of bioluminescence in a dikaryon resulting from a cross of two nonbioluminescent monokaryons. No significant differences among dikaryons were found in the characterization of bioluminescence emission spectra regardless of monokaryon composition.

Sexual compatibility of clinical and environmental isolates of Cryptococcus neoformans.

In vitro study to determine the sexual compatibility of 26 Cryptococcus neoformans isolates was conducted on sunflower (Helianthus annus) seed agar. Among 26 isolates examined, 14 were originated from animals, 6 from men and 6 from environmental substrates; 17 isolates were obtained in Japan and 9 in India. These isolates were crossed with each of the 2 mating types (α and a) of Filobasidiella neoformans var. neoformans or F. neoformans var. bacillispora. All the isolates produced basidiospores, basidia, dikaryotic hyphae with clamp connections when paired with the “a” mating type of F. neoformans var. neoformans. We could not find any isolate showing sexual reproduction with “α” mating type of either variety of F. neoformans. Furthermore, none of the isolates exhibited self-fertile behavior. Our results indicate that the “α” mating type occurs more frequently in both clinical and natural isolates of C. neoformans originated from Japan and India.

Isolation of Cryptococcus neoformans var. neoformans from canine otitis

Cryptococcus neoformans was demonstrated in the clinical material of a 15-year-old male dog with a history of chronic otitis externa by employing Helianthus annuus seed agar as a selective medium. The examination of the isolate for sexual compatibility on modified Helianthus annuus seed medium revealed that it belonged to Filobasidiella neoformans var. neoformans 'alpha' mating type. In the authors' view, this appears to be the first report of isolation of Cr. neoformans var. neoformans from diseased ear of a dog.

Failures of Volition: Female Agency and Infertility in Historical Perspective

Travel for this study was supported by a University of North Carolina at Chapel Hill Foundation Fund award. 1Infertility: Medical and Social Choices, U.S. Congress, Office of Technology Assessment, OTA-BA-358 (Washington, D.C.: Government Printing Office, May 1988), 49-57. Until 1982, data on the prevalence of infertility were not reliable, and today there is still no conceptual or methodologic consensus concerning how to determine its prevalence. The literature on infertility characteristically refers to the rising incidence of this dysfunction, but there is no hard evidence that the percentage of marital pairs in the United States unable to have the children they desire has, over the past century, been lower than 10 percent or higher than 20 percent. Within any one time period, estimates vary over this range. Although changes in the incidence of infertility in subgroups, such as black women, and in the incidence of certain diseases or conditions associated with infertility, such as venereal diseases and dietary deficiencies, have occurred, the overall prevalence appears to be rather stable. See W. R. Keye, "Psychosexual Responses to Infertility," Clinics in Obstetrics and Gynecology 27 (September 1984): 760-66, esp. 760; P. Cutright and E. Shorter, "The Effects of Health on the Completed Fertility of Nonwhite and White U.S. Women Born between 1867 and 1935," Journal of Social History 13 (Winter 1979): 191-217; E. Shorter, A History of Women's Bodies (New York: Basic, 1982), esp. 266-67, and "Women's Diseases before 1900," in New

The development of bridge lines for interspecific gene transfer between Lycopersicon esculentum and L. peruvianum

Using a modified embryo callus culture technique, hybrids between Lycopersicon esculentum and L. peruvianum were developed and their usefulness as bridge lines for facilitating interspecific gene transfer was evaluated. Four of these lines showed a high level of sexual compatibility with several other L. peruvianum var. typicum accessions, as well as with accessions of L. peruvianum var. humifusum and L. peruvianum var. glandulosum and L. esculentum. These bridge line x L. peruvianum hybrids could be crossed with L. esculentum to introgress genes from L. peruvianum into L. esculentum.

Noncorrespondence of Breeding Groups, Morphology, and Monophyletic Groups in Spirogyra (Zygnemataceae: Chlorophyta) and the Application of Species Concepts

Recent findings on the effects of polyploidy on morphology in filaments of the common green alga Spirogyra invalidate the reliance on several characters used to erect the 386 species described for this genus. Spontaneous ploidal changes have been observed that induce significant morphological changes in filaments, such that members of a series of ploidal variants would be identified as different species according to conventional taxonomy. Grouping filaments into species based on morphology (qualitative and quantitative differences between character states), breeding groups (sexual compatibility or lack thereof), or monophyly (lineages of filaments estab- lished through laboratory culture work) results in groups, or species, that differ in membership. Strains of identical morphology are not always more closely related to each other than to morpho- logically distinct ploidal variants descended from them. Nor are such ploidal variants sexually compatible with their parental strains except to a limited degree. Thus, a single monophyletic group of filaments (descended from and including an ancestral strain) may contain sexually incompatible filaments that differ greatly in morphology. This noncorrespondence of morphology, breeding groups, and monophyly suggests that conventional taxonomic monographs that distinguish species on the basis of morphology alone describe only part of the species picture, although they are still valuable as sources of information on phenotypic variability. Additional study of these three group- ing criteria in Spirogyra is needed to develop a satisfactory species concept for this genus and others in the family Zygnemataceae.

Sexual compatibility types of Bremia lactucae isolates originating from Lactuca serriola

Results are given on the occurrence of sexual compatibility types of seven isolates ofBremia lactucae originating fromLactuca serriola (prickly lettuce). It is concluded that the isolates studied are heterothallic. Both compatibility types (B1 en B2) were determined, but type B2 was prevalent. Sexual recombination ofB. lactucae isolates originating from wild and cultivated lettuce may occur.

Transfer of radish (Raphanus sativus L.) chloroplasts into cabbage (Brassica oleracea L.) by protoplast fusion.

Intergeneric hybrid plants were obtained through protoplast fusion between red cabbage (Brassica oleracea L.) and radish (Raphanus sativus L.). Protoplast fusion was carried out by the dextran method using protoplasts from hypocotyls and cotyledons of both cabbage and radish. The selection of somatic hybrids utilized the inactivation of cabbage protoplasts with iodoacetamide and the low cell-division ability of radish protoplasts. Ten plants were regenerated from selected colonies. Two of them developed to the flowering stage and formed male sterile flowers, which showed cytoplasmic inheritance. The plant and leaf morphology, chromosome number, acid phosphatase and peroxidase isozyme patterns, sexual compatibility, and SmaI cleavage patterns of chloroplast DNA indicated that these plants were intergeneric hybrids having the nucleus of cabbage and chloroplasts of radish.

Compatibility Among Host-Specialized Isolates ofHeterobasidion annosumfrom Western North America

Harrington, T. C., Worrall, J. J., and Rizzo, D. M. 1989. Compatibility among host-specialized isolates of Heterobasidion annosum from western North America. Phytopathology 79:290-296. Host-specialization of isolates of Heterobasidion annosum from from another 18 trees and stumps in Pacific Coast states also fell into the S California was previously demonstrated by inoculating Pinus ponderosa and P groups based on compatibility; those from diseased pine trees were and Abies concolor (white fir) seedlings in the greenhouse. In the present P-compatible and those from other host genera were S-compatible. study, 18 of these isolates were tested for sexual compatibility in hetero- However, compatibility of isolates and strains from stumps with S and P karyon-homokaryon pairings with six S and four P tester strains of H. testers was not consistent with the host genus, indicating that stump annosum from Europe representing two intersterility groups. colonization can be non-host specific. When North American strains were Compatibility was determined by the presence of clamp connections in paired among themselves or with heterokaryotic isolates, the two subcultures from the homokaryotic tester mycelia taken 5 wk after pairing, compatibility groups were less evident than when European strains were The nine isolates specialized to fir seedlings were compatible with S testers, used. Reports thus far suggest that both the S-compatible and Pand the nine isolates specialized to pine seedlings were compatible with P compatible groups are widespread in western North America, but only the testers. Some P-compatible isolates formed clamps with a few S testers. P group has been reported in eastern North America. Heterokaryotic isolates and homokaryotic (single-basidiospore) strains

Inheritance of Some Genetic Markers in Cochliobolus Sativus

Click to increase image sizeClick to decrease image sizeKey Words: Cochliobolus sativusGeneticsunisexuality

Sexual Behaviour and Mating System of Botryotinia fuckeliana, Teleomorph of Botrytis cinerea

Analysis of 213 field isolates of Botrytis cinerea and 240 ascospore isolates of its sexual form Botryotinia fuckeliana indicated that sexual compatibility of this fungus is controlled by a single mating type gene with two alleles. Most isolates were heterothallic, that is, they were self-sterile and able to produce ascospore progeny when crossed with reference strains carrying the mating type gene MAT1-1 or MAT1-2. About 16% of the field isolates and 6% of the ascospore progeny were homothallic, that is, self fertile and compatible with both MAT1-1 and MAT1-2 strains. Both mating types are widespread in nature. The close association of MAT1-1 and MAT1-2 field isolates on various hosts in several regions of Italy shows that sexual reproduction and meiotic recombination might be an important source of genetic variation in this pathogenic fungus.