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Abstract: A bioassay-guided phytochemical analysis of the triterpene saponins from under ground parts of Gypsophila arrostii var. nebulosa allowed the isolation of two triterpene saponins; nebuloside A, B based on gypsogenin and quillaic acid aglycone. Two new oleanane type triterpenoid saponins (nebuloside A, B) and three known saponins (1–3) were isolated from the root bark of Gypsophila arrostii var. nebulosa. The structures of the two new compounds were elucidated as 3-O-β-d-galactopyranosyl-(1→2)-[β-d-xylopyranosyl-(1→3)]-β-d-glucuronopyranosyl quillaic acid 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside A) and 3-O-β-d-xylopyranosyl-(1→3)-[β-d-galactopyranosyl(1→3)-β-d-galactopyranosyl-(1→2)]-β-d-glucuronopyranosyl gypsogenin 28-O-β-d-glucopyranosyl-(1→3)-[β-d-xylopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)]-α-l-rhamnopyranosyl-(1→2)-β-d-fucopyranosyl ester (nebuloside B), on the basis of extensive spectral analysis and chemical evidence. Nebuloside A and B showed toxicity enhancing properties on saporin a type-I RIP without causing toxicity by themselves at 15μg/mL. [Copyright &y& Elsevier]

The virulence of the bacterium Pantoea agglomerans pv. gypsophilae ( Pag) on Gypsophila paniculata depends on a type III secretion system ( T3SS) and its effectors. The hypothesis that plant-derived indole-3-acetic acid ( IAA) plays a major role in gall formation was examined by disrupting basipetal polar auxin transport with the specific inhibitors 2,3,5-triiodobenzoic acid ( TIBA) and N-1-naphthylphthalamic acid ( NPA). On inoculation with Pag, galls developed in gypsophila stems above but not below lanolin rings containing TIBA or NPA, whereas, in controls, galls developed above and below the rings. In contrast, TIBA and NPA could not inhibit tumour formation in tomato caused by Agrobacterium tumefaciens. The colonization of gypsophila stems by Pag was reduced below, but not above, the lanolin- TIBA ring. Following Pag inoculation and TIBA treatment, the expression of hrp L (a T3SS regulator) and pag R (a quorum-sensing transcriptional regulator) decreased four-fold and that of pth G (a T3SS effector) two-fold after 24 h. Expression of PIN2 (a putative auxin efflux carrier) increased 35-fold, 24 h after Pag inoculation. However, inoculation with a mutant in the T3SS effector pth G reduced the expression of PIN2 by two-fold compared with wild-type infection. The results suggest that pth G might govern the elevation of PIN2 expression during infection, and that polar auxin transport-derived IAA is essential for gall initiation. [ABSTRACT FROM AUTHOR]

The soil properties of the annual Gypsophila L. taxa of Turkey and their effects on plant morphology were investigated. The taxa studied were Gypsophila heteropoda Freyn & Sint., G. parva Barkoudah, G. elegans M.Bieb., G. bitlisensis Barkoudah, G. viscosa Murray, G. antari Post & Beauverd, G. muralis L., G. tubulosa (Jaub. & Spach) Boiss., G. confertifolia Hub.-Mor., and G. pilosa Hudson. The soils of the plant taxa were medium textured, sand or sandy-loam, saltless or a little salty, neutral, limy, rich in potassium and with very little phosphorous, and with medium levels of nitrogen and organic matter. G. antari, which had the greatest lime content, had the lowest number of leaves. G. muralis and G. tubulosa had the lowest saturation values and lime content but the greatest number of leaves. If the lime content increased, the development of roots decreased, and when the rate of sand increased, the development of roots increased. For G. muralis, phosphorus concentration, seed size, and salt content were negatively related to number of leaves. For G. tubulosa and G. antari, potassium and organic matter concentrations were negatively related to number of leaves. In G. muralis, salt content was positively related to calyx diameter and seed size. In G. confertifolia, organic matter content was positively correlated with height of the calyx, petal, and bract. It was observed that G. pilosa, G. bitlisensis, and G. viscosa species are also distributed in limeless steppe areas. The most important distribution areas of the species in Turkey are Sivas, Erzincan, Çankırı, Eskişehir, and Ankara. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine the antioxidant system responses of a xerophytic plant to salinity and drought, which were not elucidated before. Physiological and antioxidant responses of the xerophytic plant Gypsophila aucheri Boiss. were investigated under salinity (100 and 300 mM NaCl) and drought (withholding watering) treatment for 2 weeks in a controlled growth chamber. Besides growth responses (relative growth rate (RGR)), superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), and glutathione reductase (GR) activities, and SOD and CAT isoenzymes activities were determined under stress conditions. Moreover, the level of lipid peroxidation was determined as thiobarbutiric acid reactive substances (TBARS) content. Tolerance of G. aucheri to salinity and drought was evaluated based on lipid peroxidation (oxidative damage) and RGR. According to the experiments, G. aucheri was found to be tolerant to drought and 100 mM NaCl and its antioxidant system was able to cope with oxidative stress under these conditions. However, 300 mM NaCl treatment had detrimental effects on plant growth and membrane integrity. Under this concentration, oxidative stress cannot be precluded in spite of increased SOD, POX, and APX activities. These data indicate that xerophytic G. aucheri is a moderate halophytic plant that uses an efficient antioxidant defence mechanism under salinity. [ABSTRACT FROM AUTHOR]

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The Turkish ecotype of Puccinellia distans displays exceptional boron (B) tolerance, >1,250 mg B L, compared to <50 mg B L for Gypsophila arrostil. In the present study, we compare the molecular basis for the difference in B tolerance between the two species by constructing high B-responsive suppression subtractive hybridization libraries to identify the upregulated genes. A total of 219 and 113 unique non-redundant expressed sequence tags (ESTs) were identified and functionally classified in P. distans and G. arrostil, respectively. In addition, 63 ESTs were down-regulated in P. distans in response to high B. The majority of the high B upregulated genes belong to four categories: metabolism, protein synthesis, cellular organization, and stress/defense. We hypothesize that the superior B tolerance exhibited by P. distans may be due to its ability to restrict the accumulation of B in plant tissues through the upregulated expression of efflux transporters comparable to the Bot1 transporter of barley. In addition, our results are consistent with the view that other molecular mechanisms involved in stress/defense, such as detoxification, anti-oxidative, and signaling pathways, are needed to tolerate B-toxicity stress. Key message The molecular basis of boron tolerance of two plant species ( Puccinellia distans and Gypsophila arrostil) that differ greatly in their boron tolerance was studied in this manuscript. [ABSTRACT FROM AUTHOR]

Abstract: Alcohol abuse is one of the major causes of liver fibrosis, which shows a sharply increasing trend worldwide, yet effective therapeutic options for advanced alcohol fibrosis are limited. Recently we investigated the effect of anti-fibrosis by isoorientin-2″-O-α-l-arabinopyranosyl (IOA) isolated from Gypsophila elegans. During the experiment, the model group received alcohol only, and treatment groups received the corresponding drugs plus alcohol respectively, while the normal control group received an equal volume of saline. Analysis at the end of 24-week experiments showed that IOA could significantly improve the liver function, as indicated by decreasing levels of alanine transaminase, aspartate transaminase, alkaline phosphatase, γ-glutamyltransferase, interleukin-6 and tumor necrosis factor-α. Moreover, IOA could effectively inhibit collagen deposition and reduce the pathological tissue damage. Research on mechanism showed that IOA was able to markedly reduce lipid peroxidation, recruit the anti-oxidative defense system, and induce HSC apoptosis by down-regulating bcl-2 mRNA, as well as inhibit the expression of α-smooth muscle actin and transforming growth factor β1 proteins. In short, our results showed that IOA is effective in attenuating hepatic injury and fibrosis in the alcohol-induced rat model, which should be developed as a new drug to treat liver fibrosis and even cirrhosis. [Copyright &y& Elsevier]

Abstract: Salinity is a major limiting factor to agricultural productivity. To ensure future productivity of the agricultural regions and achieve a selection of genetically transformed salt-tolerant plants, there is a need to select and characterize salt-tolerant plants. Gypsophila oblanceolata Bark. is a Turkish endemic and endangered halophyte occurring in salt marshes/hydromorphic soils. The aim of this experiment was to determine the responses of G. oblanceolata to salt stress during germination and vegetative growth. Therefore, effects of salinity (0, 50, 100, 150, 300mM NaCl) on germination and changes in the activities of antioxidant enzymes/isoenzymes (SOD, CAT and POX) during germination under stress and recovery after stress were determined. Moreover, during vegetative growth (60d old plants), changes in physiological parameters, ion concentrations, proline (Pro) content, lipid peroxidation (MDA), H2O2 content, NADPH oxidase activity and, antioxidant enzyme/isoenzyme system (superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), glutathione reductase (GR)) were also investigated. Salt stress decreased both the germination percentage and rate. Few seeds germinated at 100mM NaCl. Exposure to high concentrations of NaCl did not permanently inhibit germination. Salinity (50mM NaCl) caused a decrease in activities of SOD, CAT and POX during germination. However, after stress, the activities of all enzymes were increased in recovered-plants. During vegetative growth, increased activities of SOD, CAT and APX in 50 and 100mM NaCl treated-plants may help to avoid oxidative damage in G. oblanceolata. However, at higher doses, induced stimulation of the CAT, POX and GR was not sufficient to cope with the enhanced ROS production and MDA level. From the results obtained in present study, it can be suggested that G. oblanceolata is a moderately salt-tolerant species. Differential responses of antioxidant enzymes to salt stress during germination and vegetative growth suggested different antioxidant metabolism in G. oblanceolata. [Copyright &y& Elsevier]

Gypsophila turcica Hamzaoğlu is described as a new species. The specimen was collected from gypsaceous hills, at an altitude between 1755 and 1835 m from Zara District (Sivas Province). The new species is similar to Gypsophila festucifolia Hub.-Mor. The differences between these 2 taxa are discussed. Moreover, Silene choruhensis Hamzaoğlu nom. nova should replace S. ispirensis A.P.Khokhr. 1997, which is an illegitimate name as a younger homonym of S. ispirensis Boiss. 1856. [ABSTRACT FROM AUTHOR]

Abstract: Gypsum soils are among the most restrictive substrates for plant life, yet the mechanisms of plant adaptation to gypsum are still poorly understood. Arbuscular mycorrhizal fungi (AMF) can improve host plant nutrition and survival in stressful environments but little is known about the ubiquity and function of AMF in plants that grow in gypsum soils, both specialists and generalists. Previous studies indicate that most gypsophiles (specialists) show much higher concentration of nutrients than gypsovags (generalists), hence our hypothesis was that this would be related to increased mycorrhizal colonisation in gypsum specialists. We therefore quantified colonisation of the roots by mycorrhizal arbuscules (AC), vesicles (VC) and hyphae (HC) in six species of gypsophiles and six species of gypsovags growing in gypsum outcrops. Both groups of plants showed significant differences in AC, VC and HC but in contrast to our hypothesis, colonisation was greater in gypsovags than in gypsophiles. The extent of AMF colonisation does not seem to explain the distinctively high nutrient concentrations reported for gypsophiles. Our results indicate that increased AM colonisation could be a mechanism allowing non-specialist plants to cope with the restrictive conditions of gypsum. [Copyright &y& Elsevier]

In order to examine the systematic application of seed-coat micro-morphology in Gypsophila and allied genera, seed surfaces of 30 species and two varieties representing four genera of tribe Caryophylleae were examined with scanning electron microscope. The seeds of examined species range between 0.5-2.1 mm in length and 0.3-2.4 mm in diameter. The exomorphology of the seed coat shows two distinctive cell patterns. The epidermis is constructed either of elongated polygonal or of broad polygonal cells. The elongated type is the most common among the studied species, but the variation in alignment of testa cells, their size and shape as well as the density of protuberances may provide further information and useful diagnostic characters at generic and specific rank. The testa cells in Gypsophila and Saponaria are shallowly undulate, deeply undulate, lobed and armed at anticlinal walls. Deeply undulate anticlinal walls were observed in both Gypsophila and Ankyropetalum and a few species of Saponaria. Non- or indistinctly grooved anticlinal walls is the more common type in Allochrusa. Seed-coat characters support the separation of Gypsophila and Saponaria to some extent but disagree with recognition of Ankyropetalum as a genus separate from Gypsophila. [ABSTRACT FROM AUTHOR]

The goal of this study is revision of morphological and systematical characters of the taxa in Macrorrhizaea Boiss. section of Gypsophila L. genus of Türkiye. Three species of Macrorrhizaea Boiss. section (G. muralis L.,G. tubulosa (Jaub.& Spach) Boiss. and G. confertifolia Hub.-Mor.) were selected as study material. All of the species have annual life formation. G. muralis is narrowly ranged, Euro-Siberian element. G. tubulosa is endemic, East Mediterranian element, and G. confertifolia is endemic, East Mediterranian element. Number of localities where the the specimens of species were collected are: G. muralis 3, G. tubulosa 7, G. confertifolia 5 and G. pilosa 26. For each species, about 70 morphological characters were examined, biometric datas were analysed statistically and the results were interpreted. In addition, a comparison between all of the findings and literatures was done. G. muralis which can be easily distinguished with very weak roots and delicate stems and grows only in Tekirdağ. Hair properties are very important for G. tubulosa. There are long glandular hairs on upper parts and short a-glandular hairs in under parts of the stem. Differentiating characters of G. confertifolia are their root lengths are generally longer than the stem lengths and capitat inflorescence. As a resut; systematical and morphological investigations were done on Gypsophila species of Macrorrhizaea section of Türkiye. 45 new characters for G. muralis, 36 new characters for G. tubulosa and 39 new characters for G. confertifolia were added to definitions of the species. 11 characters for G. muralis, 9 characters for G. tubulosa and 18 characters for G. confertifolia have been found as different from present literature. [ABSTRACT FROM AUTHOR]

The effects of light quality on flowering time were investigated in Gypsophila paniculata, which is a long-day cut flower, and with Arabidopsis under long-day conditions with light-emitting diodes (LEDs). Gypsophila paniculata plants were grown under natural daylight and flowering was controlled by long-day treatment with a weak LED light of a single color in the night. Flowering was promoted not by blue light, but by far-red light in G. paniculata, while flowering was promoted by both light colors in Arabidopsis. FT homologs of G. paniculata GpFT1 and GpFT2 were differentially expressed under long-day conditions with white light, suggesting that they play roles in flowering at different stages of reproductive development. GpFTs and FT gene expression was not induced by far-red light in G. paniculata or Arabidopsis. Instead, the expression of the SOC1 homolog of G. paniculata GpSOC1 and SOC1 was induced by far-red light in G. paniculata and Arabidopsis. Flowering was promoted by induction of FT and SOC1 expression with blue light in Arabidopsis, whereas GpFTs and GpSOC1 expression was low with blue light induction in G. paniculata. The relationship between flowering and the expression of FT and SOC1 in Arabidopsis was confirmed with ft and soc1 mutants. These results suggest that long-day conditions with far-red light promote flowering through SOC1 and its homologs, while the conditions with blue light do not promote flowering in G. paniculata, because of low expression of GpFTs and GpSOC1 in contrast to that in Arabidopsis. [ABSTRACT FROM AUTHOR]

Gypsophila tomentosa and G. struthium are closely related species, characteristic of two European priority habitats, salt and gypsum inland steppes, respectively. Germination strategies of the two taxa were investigated in plants from two nearby populations, growing under the same climatic conditions but on different types of soil, and belonging to different plant communities. heir germination patterns were studied at five constant temperatures in darkness: 5°C, 10°C, 15°C, 20°C and 25°C, and the base temperature and the thermal time requirement were calculated. As the distribution area of both species is subjected to a Mediterranean continental climate with significant differences between day and night, the possible preferences for an alternating temperature regime (25/10°C) were contrasted, as well as the influence of cold stratification and freezing. The effects on seed germination of light at constant 20°C and a 12/12 h photoperiod were also compared in the two species. he main conclusions of the work are the similarity of behaviour of both species, with an absence of seed dormancy, their opportunistic germination strategy, and water availability as the principal limitation to seed germination and plant establishment. he base temperature and thermal time indicate higher competitiveness of G. struthium at low temperatures, but seed germination of G. tomentosa is the most efficient at temperatures higher than 13.3°C. Optimal temperature and illumination conditions for nursery propagation depend on the species. he high viability of seeds observed after freezing prove the orthodox character of these seeds, providing additional information for long term seed conservation procedures. [ABSTRACT FROM AUTHOR]

The antioxidant effect of saponarin, which is the main flavone isolated from Gypsophila trichotoma Wend., and its protection against cocaine hepatotoxicity were investigated in male Wistar rats. The animals were treated with cocaine (40 mg/kg i.p.) alone and also after 3 consecutive days of pretreatment with saponarin (80 mg/kg p.o.). After 18 hours the rats were sacrificed by decapitation. The production of thiobarbituric acid reactive substances, reduced glutathione (GSH) and the activity of the following antioxidant enzymes: catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione-S-transferase were assessed in liver homogenate. Administered alone, cocaine induced significant hepatotoxicity manifested with GSH depletion and reduced antioxidant defences. Saponarin pretreatment, however, decreased cocaine toxicity both by increasing GSH levels and antioxidant enzyme activities. The results of this study proved the antioxidant activity of saponarin and its protective effect against cocaine-induced oxidative stress and hepatotoxicity. [ABSTRACT FROM AUTHOR]

During the last decade, the paradigm that low toxicant doses often have stimulatory effects on plants has become widely accepted. At the same time, low toxicant doses of metal salts have been observed to inhibit the growth of the most vigorous seedlings of a population in vitro, although mean plant size has remained unaffected. We hypothesized that this kind of selective low-dose toxicity is not restricted to inorganic contaminants. We exposed annual plants (baby's breath Gypsophila elegans, purslane Portulaca oleracea, and duckweed Lemna minor) to 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta-γ-2-benzopyran (HHCB) and 4-tert-octylphenol and lead acetate. As compared to unexposed G. elegans roots, 4-tert-octylphenol did not affect the mean root size of all seedlings, but it reduced the average length of roots longer than the 98th percentile. A comparable response was found in case of G. elegans roots treated with lead acetate beyond the 90th percentile. The average size of roots beyond the 90th percentile was decreased also when L. minor was exposed to lead acetate though the means of all roots were constant. P. oleracea seemed to be insensitive to selective toxicity. We conclude that selective toxicity at low doses should be considered in parallel with hormesis. [ABSTRACT FROM AUTHOR]

The physiological characteristics of the extremely boron (B)-tolerant plant species, Puccinellia distans, were compared with those of the moderately tolerant Gypsophila arrostil, two species collected from a B-mining area of Eskiehir, Turkey. Boron was supplied to plants hydroponically at B concentrations ranging from 0.5 to 50 mg B/L for G. arrostil, and from 0.5 to 2000 mg B/L for P. distans. The results show that P. distans has a strikingly greater tolerance to B than G. arrostil. While G. arrostil was unable to survive B supply concentrations greater than 50 mg B/L, P. distans grew at B supply concentrations exceeding 1250 mg B/L. Our research supports the conclusion that from 0.5 to 50 mg B/L, P. distans is better able to restrict the accumulation of B in the whole plant, and the transport of B from root to shoot, than G. arrostil. We propose that P. distans uses several strategies to achieve B tolerance including the ability to restrict the accumulation of B relative to its accumulation of biomass, the ability to restrict the transport of B from root to shoot, and, to a lesser extent, the ability to tolerate high concentrations of B in its shoot and root tissues. [ABSTRACT FROM AUTHOR]

Abstract: Gypsophila flowering stems are treated with a commercial formula before shipment; however, it is not clear if this treatment is the best one to enhance floret water uptake. Moreover it is not clear if it can ameliorate damage caused by exposure to air that is encountered during harvest. Water uptake by individual gypsophila florets was measured by the apoplastic fluorescent dye 8-hydroxypyrene-1,3,6-trisulfonic acid (HPTS). By employing this dye, it was determined that desiccation of flowering stems of more than 15% of their fresh weight, followed by rehydration with water, decreased floret water uptake. Reduction in water uptake was not observed in whole stems; nevertheless, floret opening was reduced. To improve floret water uptake following desiccation, the effects of rehydration with the detergents polyoxyethylene (10) lauryl ether, mixture of quaternary ammoniums, sodium dodecyl sulfate and Triton X-100 were examined. Triton X-100 was the most effective detergent in enhancing floret water uptake and it was better than TOG3 (included in the commercial formula), which was also shown to improve floret water uptake. Since flower opening was correlated with higher floret water uptake, the TOG3 in the commercial formula was replaced with Triton X-100. These solutions were equally effective in improving flower opening; however, neither completely reversed the desiccation-enhancement of flower wilting. Our results support the notion that water absorption by florets is not the sole contributor to flower opening. Taken together, our results suggest that it is possible to replace TOG3 with Triton X-100 in the commercial formula and rehydration with this solution following desiccation can overcome the reduction in floret water uptake. [Copyright &y& Elsevier]

Abstract: A simple and rapid method of excised root cultures from six Gypsophila species was performed allowing continuous growth without phytohormones. Established on MH3 medium from solid-grown seedlings these roots were subcultured for 1 year on a solid medium before being transferred in a liquid medium to obtain substantial biomass for saponin content analysis. Morphologically, the different root lines presented different growth behaviors and different physical aspects: some have linear growth by the tip of the main axial root from the original seedling; others have additional lateral root initiations producing a hairy root-system more or less dense. A marked increase of biomass was observed in the light by comparison with dark conditions. Significant growth for Gypsophila glomerata was achieved within 3 weeks on liquid medium; biomass grew up to 50-fold in batch cultures reaching 10gDW. The fingerprints of the saponin HPLC profiles of the six Gypsophila species were drastically different with at least up to 30 different saponins detected for some of them. The roots of Gypsophila elegans accumulated saponins up to 65mg/gDW. These amounts were higher than in Gypsophila paniculata roots classically found as the best producing ones. On the contrary the root lines of G. glomerata showed a smaller quantitative amount of saponins (between 1.3 and 7.10mg/gDW) than those of G. elegans but nearly the same HPLC profiles as for root extracts of G. paniculata plants grown directly in the fields. [Copyright &y& Elsevier]

Abstract: Six new triterpenoid saponins (1–6) have been isolated from the roots of Gypsophila pacifica Kom. Their structures were established on the basis of extensive NMR (1H, 13C, TOCSY, HSQC, and HMBC) and ESIMS studies. [Copyright &y& Elsevier]

Abstract: Saporin is a type I ribosome-inactivating protein with N-glycosidase activity. It removes adenine residues from the 28S ribosomal RNA resulting in inhibition of protein synthesis. Recently we have shown that saporin exerts no cytotoxicity on seven human cell lines. However, the combination of saporin with a special mixture of Gypsophila saponins (Soapwort saponins) from Gypsophila paniculata L. (baby''s breath) rendered saporin to a potent cytotoxin comparable to viscumin, a highly toxic type II ribosome-inactivating protein. In this study we investigated whether the enhancement of the saporin-cytotoxicity by Gypsophila saponins is mediated by a saponin-triggered modulation of endocytosis, exocytosis or impaired degradation processes of his-tagged saporin (hissaporin) in ECV-304 cells. For this purpose hissaporin was labelled with tritium and cytotoxicity of the toxin alone and in combination with Gypsophila saponins was scrutinized. The transport and degradation processes of hissaporin were not different in Gypsophila saponin-treated and control cells. However, after ultracentrifugation of a post-nuclear supernatant the amount of cytosolic hissaporin was significantly higher in saponin-treated cells than in cells, which were only incubated with hissaporin. This indicates a saponin mediated endosomal escape of saporin. [Copyright &y& Elsevier]

Five new isolates of carnation Italian ringspot virus (CIRV) from cherry trees, Gypsophila and surface water differ from the original carnation isolate (CIRV-car) and also from Pelargonium necrotic spot virus (PelNSV) by having an ORF 1/ORF1-RT with a typical tombusvirus-like 5′end and by inducing the formation of peroxisome- rather than mitochondrion-derived multivesicular bodies (MVBs). This supports with natural isolates earlier conclusions reached by others with artificially produced hybrid viruses that the 5′end of ORF 1 determines from which organelle the MBVs will be derived. CIRV-car might have resulted from a natural recombination event with genome elements of a PelNSV-like virus. [ABSTRACT FROM AUTHOR]

Pollen morphology of 12 taxa (6 of them endemic) that belong to the genus Gypsophila L. were investigated using light microscopy (LM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Differences in pollen morphology between these taxa were determined based on palynological studies. Pollen grains are spheroidal and polyporate. The exine structure is tectate, but that of G. sphaerocephala var. sphaerocephala is intectate. The exine sculpture is granulate-microechinate-microperforate, but that of G. sphaerocephala var. sphaerocephala displays clavate-microechinate ornamentation. The operculum exists in the form of scattered pieces in G. curvifolia, while it exists as a whole in the other taxa. G. perfoliata var. perfoliata has the largest pollen grain diameter, whereas G. tubulosa has the smallest. The exine consists of 2 parts; the upper part is the thick ectexine and the lower part is the thin endexine. The endexine is thin and continuous. [ABSTRACT FROM AUTHOR]

The community composition of arbuscular mycorrhizal fungi (AMF) was analyzed in roots of Gypsophila struthium growing in gypsum soils under semiarid conditions. In order to investigate the effect of plant community degradation on the AMF biodiversity at the single species level, on the basis of the plant community complexity level, we selected four areas affected by degradation and shrub species spatial heterogeneity. The AM fungal community colonizing G. struthium was investigated from the morphological and molecular points of view. All plants were well colonized and showed a high level of infective AM propagules. Roots were analyzed by polymerase chain reaction, restriction fragment length polymorphism screening, and sequence analyses of the ribosomal DNA small subunit region. Four AM fungal types were identified and clustered into the AM fungal family: Glomeraceae, Glomus being the only taxon present. One fungal type was present in all the selected areas. Two fungal types are distinct from any previously published sequences and could be specific to gypsum soils. The chemical–physical properties of the soil were not correlated with the AMF diversity in roots. Our data show vegetation cover complexity-dependent differences in the AM fungal community composition. [ABSTRACT FROM AUTHOR]

Abstract: The unique physical and chemical properties of gypsum soils have been used to explain species distribution across landscapes, however, past research on gypsophiles often has not encompassed broad analysis of soil–landscape–plant interaction and thus may have incorrectly labeled many species as gypsophiles. We use the example of the two reported gypsophiles, Arctomecon californica Torrey & Frémont and Eriogonum corymbosum Bentham var. nilesii Reveal found in the southern Mojave Desert, USA, to test the hypothesis that both species are gypsophiles and then draw conclusions from our work to evaluate past studies of gypsum soils, their landscapes and gypsophiles. Results from detailed pedologic analyses indicate that site characteristics affecting potential soil water content (topgraphic relief, soil particle size, depth to horizons perching water, and soil chemistry and mineralogy) differentiate habitat types and suggest surface differences affecting soil water content are more important for species success than sub-surface factors. Results suggest that gypsum is but one part of the explanation for A. californica and E. corymbosum habitat differentiation and in fact neither species are gypsophiles. While few soils across all habitats had abundant gypsum, gypsum was of very low abundance at most sites and not limited to one habitat type. Foliar chemistry data also indicate neither species accumulates sulfur; the hypothesis that these species are gypsophiles is thus rejected. This research demostrates the complicated nature of determining the influence of soil and landscape on habitat differentiation and the necessity of detailed field-pedologic analysis when defining species limiting soil-landscape constraints. [Copyright &y& Elsevier]

As a major contributor to the flower market, Gypsophila paniculata is an important target for the breeding of new varieties. However, gypsophila breeding is strongly hampered by the sterility of this species’ genotypes and the lack of a genetic-transformation procedure for this genus. Here we describe the establishment of a transformation procedure for gypsophila ( Gypsophila paniculata L.) based on Agrobacterium inoculation of highly regenerative stem segments. The transformation procedure employs stem explants derived from GA3-pretreated mother plants and a two-step selection scheme. The GA3 treatment was crucial for obtaining high gene-transfer frequencies (75–90% GUS-expressing explants out of total inoculated explants), as shown using three different gypsophila varieties. An overall transformation efficiency of five GUS-expressing shoots per 100 stem explants was demonstrated for cv. Arbel. The applicability of the transformation system to gypsophila was further reinforced by the generation of transgenic plants expressing Agrobacterium rhizogenes rolC driven by a CaMV 35S promoter. Transgenic gypsophila plantlets exhibited extensive rooting and branching, traits that could be beneficial to the ornamental industry. [ABSTRACT FROM AUTHOR]

Soaproot (Radix Gypsophilae) is an important herbal drug having medicinal and economic importance and has been collected from nature for more than 30 years. The main goal of this study was to determine soaproot yielding plant species in East Anatolia, and their potential in nature. Collected plants were determined by field studies; damage to the environment after collection was observed, and commerce, exportation, domestic utilisation of soaproot, and problems and proposed solutions were examined. Soaproot is presently obtained from a total of 7 plant species belonging to 2 genera in Turkey (6 Gypsophila L., 1 Ankyropetalum Fenzl): G. graminifolia Bark, G. arrostii Guss. var. nebulosa (Boiss. & Heldr.) Bark., G. eriocalyx Boiss., G. bicolor (Freyn & Sint.) Grossh., G. perfoliata L., G. venusta Fenzl, and Ankyropetalum gypsophiloides Fenzl. It is determined for the first time that G. graminifolia is also being collected as soaproot from Van province. [ABSTRACT FROM AUTHOR]

To answer the question whether flowers wave to attract pollinators, we determine: (1) the heritability of floral mobility; (2) whether wavy flowers attract more insects; (3) does the duration of pollination affect seed set; and (4) the relationship between seed set and floral mobility. The pollination ecology of Silene maritima was investigated. Flowers on stalks of different waviness were used to investigate the effect of floral movement on pollinator visits. There is heritable variation in both direct and indirect estimates of floral mobility. The highest insect total visitation times were associated with medium length thin stalks that were visited more frequently and by more insect species. Although mean individual visit durations were less than those of less mobile flowers, this was compensated for by increased visits. Observations of controlled pollinations show that when the visit times are low, so is seed set and therefore low and high mobility flowers might suffer from reduced fitness. Combining these observations provides a mechanism that could be driving stabilizing selection for flower stalk traits, with a trade-off applying between waving to attract pollinators and not being too mobile as to prevent effective pollination. Further evidence for stabilizing selection is provided by the relationship observed in the field between seed set and floral mobility where the highest levels of fitness was associated with intermediate levels of floral waving. [ABSTRACT FROM AUTHOR]

The article examines the impact of habitat fragmentation and livestock grazing on gypsum plant communities and whether they produce different effects in specific gypsum specialists compared to habitat generalists, by conducting a vegetation survey in Europe's largest gypsum outcrop in Middle Ebro Valley, Northeast Spain. Findings show that there are lower plant species diversity in fragmented areas while plant species richness and similarity in plant species composition are larger in grazed sites. Results also reveal that gypsum specialists are significantly lesser in fragmented sites while grazing resulted to the disappearance of the rare gypsum, Campanula fastigiata.

Abstract: An unusual new cyclic peptide with a pyrrolidine-2,5-dione unit, gypsophin (1), was isolated from Gypsophila oldhamiana. Its structure was elucidated by the spectroscopic evidences. The stereochemistry was determined by application of the Marfey’s method and the single-crystal X-ray diffraction. Compound 1 exhibited inhibitory activity against α-glucosidase with IC50 of 305μM. [Copyright &y& Elsevier]

Four successive trials with gypsophila, rose, cucumber, and lettuce grown on different pumice grades were conducted in a heated glasshouse. In the gypsophila experiment, three grades of pumice (0 to 2, 0 to 5, and 0 to 8 mm) were tested, whereas in the rose, cucumber, and lettuce experiments, four pumice grades (0 to 2, 0 to 5, 0 to 8, and 4 to 8 mm) were compared. In each experiment, these pumice grades were combined with two growing systems, specifically placement of the same media volume either in pots or in bags. Furthermore, the physical properties of the tested pumice grades were determined. Overall, gypsophila and cucumber gave the highest yields when grown in pots filled with the two finest pumice grades, whereas the yield obtained from plants grown in bags was poor regardless of particle size range. Coarse pumice restricted gypsophyla and cucumber yield in pot culture to nearly the same degree as in bags. In contrast, lettuce, and to a greater degree roses, exhibited a weaker response to the different pumice grades and growing systems. The two finer pumice grades were characterized by relatively low air-filled porosity, which presumably restricted plant growth and yield as a result of poor root aeration when the media were placed in bags with a height of 8 cm. The coarsest pumice grades were characterized by a steep drop in the water content as the suction increased only a few centimeters above zero, which imposed an appreciable lowering of the overall water content in the pots in comparison with the bags (≈12.5%), as a result of the increased height of the former. Our results indicate that gypsophila and cucumber respond more strongly than roses and lettuce to the variations in the air-to-water ratio in the root zone originating from differences in the physical properties of the growing media. [ABSTRACT FROM AUTHOR]

The article focuses on the biogeography of gypsophily in Tiquilia subgroup Eddya, a Chihuahuan Desert plant group generally comprised of gypsophiles and gypsovags. Data show that the recent ancestor of subgenus Eddya was a gypsovag, and that gypsophily has evolved twice. DNA analyses in the subgenus reveal that the narrowly distributed gypsophiles shared a complex evolutionary history.

Iberian gypsophile plant communities are considered a priority for conservation by the European Community because of their highly specialized flora in gypsum outcrops in arid and semiarid regions. Despite the ecological importance of these ecosystems, the edaphic factors that constrain plant communities on gypsiferous soils remain unclear. It has been proposed that both the chemical and physical restrictive conditions of gypsum soils determine gypsophily in plants. Here we hypothesize that the rigors of the gypsum soil environment depends on topography, decreasing from flat areas on hilltops to south-oriented slopes and finally to slopes oriented to the north. We also hypothesized that the relaxation of the rigors of the gypsum soil environment with topography affects both to individual plant and community characteristics of gypsophile vegetation: we expect a reduction of gypsophyte abundance, an increase of diversity and the amelioration of facilitative interactions of plant species. We analysed the physical and chemical properties of gypsum soils that have been proposed that determine the rigors of the gypsum soil environment (i.e.: unbalanced ion concentrations and superficial soil crust). The predicted rigor gradient along topographical locations was confirmed and was mainly caused by superficial soil crust. The decreasing rigor gradient was accompanied by a fall in the abundance of gypsophytes. However, when gypsophytes were considered separately, several patterns were observed, indicating distinct tolerance to relaxation of rigor of the gypsum soil conditions and different competition abilities between gypsophytes. Plant species were more clumped, and gypsophile communities presented higher diversity, evenness and richness values where rigor of gypsum soil conditions were maximum (flat hilltop positions). Relaxation of rigor (north-oriented slopes) was characterized by loss of facilitative interaction between species and the dominance of the gypsovag Rosmarinus officinalis L., although richness was still very high, which can be attributed to the coexistence of gypsophytes and gypsovags. We conclude that the rigor of gypsum soil environment gradient with topography is mainly determined by superficial soil crust, and it is a crucial determinant of gypsophile plant communities. [ABSTRACT FROM AUTHOR]

Six new triterpene glycosides, repensosides A–F (1–6, resp.), were isolated from the roots of Gypsophila repens L. Their structures, established by extensive 1D- and 2D-NMR spectroscopic experiments as well as MS analyses, were found to be based on gypsogenic acid (or gypsogenin) as aglycone, with three to nine branched or unbranched sugar moieties. [ABSTRACT FROM AUTHOR]

Pantoea agglomerans pv. gypsophilae ( Pag) elicits galls on gypsophila and a hypersensitive response on beet, whereas P. agglomerans pv. betae ( Pab) induces galls on both beet and gypsophila. The pathogenicity of both pathovars is dependent on the presence of a plasmid harbouring type III secretion system (TTSS) components and effectors. The HsvG TTSS effectors of Pag (HsvG- Pag) and Pab (HsvG- Pab) determine the host specificity of both pathovars on gypsophila. Here we describe a novel HsvG homologue, HsvB, which determines the host specificity of Pag and Pab on beet. HsvG requires two direct amino acid repeats for pathogenicity on gypsophila, whereas one repeat in HsvB is sufficient for pathogenicity on beet. Exchanging repeats between HsvG- Pag and HsvB- Pab resulted in a switch of host specificities. Transient expression of GFP–HsvG or GFP–HsvB fusions in gypsophila, beet or melon leaves showed that HsvG and HsvB were localized to the nuclei of host and non-host plants. A yeast one-hybrid assay revealed that a single repeat of HsvG or HsvB was sufficient to activate transcription. By employing random binding-site selection and gel-shift assay HsvG was demonstrated to be a double-stranded DNA-binding protein with an ACACC/aAA consensus binding site. These results suggest that HsvG and HsvB are host-specificity determinants and bear the potential to affect the host transcriptional machinery. [ABSTRACT FROM AUTHOR]

Peronospora dianthicola was recorded for the first time in Israel on carnation, in February 2004. Eradication measures were taken and the production site was declared free of the disease by the end of the growing season. A survey showed that no other carnation nurseries were affected by downy mildew. A downy mildew on gypsophila, identified in 2004 and 2005, is compared here with older findings and with P. gypsophilae descriptions in the literature. [ABSTRACT FROM AUTHOR]

Background: Roots are the classical model system to study the organization and dynamics of organ growth zones. Profiles of the velocity of root elements relative to the apex have generally been considered to be sigmoidal. However, recent high-resolution measurements have yielded bi-linear profiles, suggesting that sigmoidal profiles may be artifacts caused by insufficient spatio-temporal resolution. The decision whether an empirical velocity profile follows a sigmoidal or bi-linear distribution has consequences for the interpretation of the underlying biological processes. However, distinguishing between sigmoidal and bi-linear curves is notoriously problematic. A mathematical function that can describe both types of curve equally well would allow them to be distinguished by automated curve-fitting. Results: On the basis of the mathematical requirements defined, we created a composite function and tested it by fitting it to sigmoidal and bi-linear models with different noise levels (Monte-Carlo datasets) and to three experimental datasets from roots of Gypsophila elegans, Aurinia saxatilis, and Arabidopsis thaliana. Fits of the function proved robust with respect to noise and yielded statistically sound results if care was taken to identify reasonable initial coefficient values to start the automated fitting procedure. Descriptions of experimental datasets were significantly better than those provided by the Richards function, the most flexible of the classical growth equations, even in cases in which the data followed a smooth sigmoidal distribution. Conclusion: Fits of the composite function introduced here provide an independent criterion for distinguishing sigmoidal and bi-linear growth profiles, but without forcing a dichotomous decision, as intermediate solutions are possible. Our function thus facilitates an unbiased, multiple-working hypothesis approach. While our discussion focusses on kinematic growth analysis, this and similar tailor-made functions will be useful tools wherever models of steadily or abruptly changing dependencies between empirical parameters are to be compared. [ABSTRACT FROM AUTHOR]

Original meiotic chromosome counts are presented for nine endemic species in seven families of Angiosperms from Iran including: Arum giganteum GHAHR. (Araceae) (n=14), Caccinia actinobole BUNGE (Boraginaceae) (n=8), Delphinium aquilegifolium (BOISS.) BORNM. (Ranunculaceae) (n=8), Diplotaenia damavandica MOZAFF., HEDGE et LAMOND (Apiaceae) (n=11), Gypsophila caricifolia BOISS. (Caryophyllaceae) (n=17), Iphiona arachnoidea (BOISS.) ANDERB. (Asteraceae) (n=9), Moltkia gypsacea RECH. f. et AELLEN (Boraginaceae) (n=20), Onobrychis gaubae BORNM. (Fabaceae) (n=8) and Onosma platyphyllum RIEDL (Boraginaceae) (n=9). Eight counts are reported for the first time. Furthermore, the previous chromosome count for Iphiona aracnoidea is corrected. Based on cytological data the species status of Moltkia gypsacea is confirmed; it is not merely synonymous with M. coerulea (WILLD.) LEHM. The basic chromosome number n=11 is reported in the genus Diplotaenia for the first time. [ABSTRACT FROM AUTHOR]

In gynodioecious plant species, females are expected to have more resources available for maturing seeds because pistillate flowers are smaller, do not produce pollen, and are thus less costly that perfect flowers. The potential female advantage arising from more abundant resources is, however, likely to vary depending on whether seed production is limited by resource or pollen availability. Here we experimentally investigated the influence of pollen and resource limitation on female advantage in a gynodioecious species using two levels of pollination. Total seed production of females was always greater than that of hermaphrodites: females produced more flowers and more fruits that contained similar numbers of seeds of similar mass. Under low pollination, female and hermaphrodite plants allocated resources to increased flower production rather than to increased seed size or quality. We did not detect any influence of pollen or resource limitation on female advantage, which remained similar under low (= abundant resources) and full pollination. Outcrossed fruits performed better than selfed fruits when the same plant received both selfed and outcrossed pollen on different flowers. These differences were not greater under high pollination, possibly because resources available for each fruit did not differ between our pollen intensity treatments. [ABSTRACT FROM AUTHOR]

The study of how parasites adapt to new hosts is of great importance for understanding the emergence of new diseases. Here, we report a study of the anther smut disease on Gypsophila repens (Caryophyllaceae). In contrast to what is usually found on other host species, infected natural populations of G. repens are extremely rare. Moreover, symptoms of diseased plants are incomplete and highly variable over the time. These results suggest that the fungus infecting G. repens is a case of a parasite not capable of exploiting its host optimally. Molecular analyses of Microbotryum violaceum strains infecting this and other Caryophyllaceae revealed that this sub-optimal behaviour probably resulted from a recent host shift from the morphologically similar plant Petrorhagia saxifraga. With its exceptionally low virulence and prevalence, but apparent self-sustainability, the disease on G. repens may thus represent an interesting case study for investigating the conditions leading to adaptation of parasites on new hosts. [ABSTRACT FROM AUTHOR]

Females of gynodioecious species need to have reproductive advantages to compensate for their lack of male function and assure their maintenance in natural populations. Females may be more fecund than hermaphrodites because they reallocate resources from male to female function, avoid selfing and inbreeding depression, or produce higher quality offspring by screening arriving pollen better. A novel type of female advantage is proposed that may be important for several species of gynodioecious Caryophyllaceae. The anther smut fungus Microbotryum violaceum generally sterilizes its infected hosts hut even without infection, spore deposition can negatively affect the reproduction of healthy individuals. In Gypsophila repens, flowers of hermaphrodite plants experimentally pollinated with both fungal spores and pollen produced significantly fewer fruits and seeds than those that received pollen alone, whereas female reproduction was unaffected by spore deposition, This unexplored reproductive advantage of females is probably due to the larger stigmatic surface in pistillate flowers, that allows pollen germination despite the presence of spores. Because longer stigmas may also lead to increased spore deposition, these results raise questions regarding the infection probability for each sex, possible sex-specific defense mechanisms, and the general role of pathogens in the maintenance of females in natural gynodioecious populations. [ABSTRACT FROM AUTHOR]

Abstract: Flower senescence is accompanied by the rapid death of large numbers of cells. In situ DNA degradation was studied in gypsophila (Gypsophila paniculata) petals during flower opening and senescence, using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL). In flowers that had just opened, TUNEL staining was exclusively observed in nuclei in the vicinity of (developing) vessels, presumably reflecting xylem vessel differentiation. In fully open flowers, TUNEL positive nuclei appear in all the cells well before the increase in ethylene production and visible signs of senescence. Occurrence of TUNEL positive nuclei was stimulated by ethylene but not prevented by silver thiosulphate. The results show that gypsophila petal senescence is a form of PCD with features of animal apoptosis and suggest that nuclear DNA degradation is an early regulatory event rather than a result of massive cell death in the final stage of senescence. [Copyright &y& Elsevier]

A practical very cold neutron (VCN) radiography using a neutron imaging plate was carried out in VCN facility, Kyoto University Reactor (KUR: 5 MW). The neutron flux from the VCN bender with the characteristic wavelength of 4.8 nm gives a good image with 5 min irradiation time when CNS was operated. The macroscopic total cross sections of water were measured by imaging plates. It is Σth=0.87 cm-1 measured in KUR E2 thermal neutron radiography facility and that of VCN is ΣVCN=9.4 cm-1. The resolution of water thickness is less than 0.1 mm for VCN radiography and close to the positional resolution of an imaging plate. VCN radiography can show the change of water quantity in gypsophila during a drying procedure. [Copyright &y& Elsevier]

Euphorbia acanthodes Akhani is described as a new gypsophilous species from south-west Iran. The affinity, morphological and carpological features, and habitat of the species are discussed. A list of a further 36 interesting endemic species of south-western Iran and adjacent areas is given with notes on their affinities and distribution. These include Centaurea gudrunensis Boiss. & Hausskn., as a new record from Iran. The specific status of Pteropyrum naufelum Al-Khayat is confirmed and it is suggested that P. noëanum Boiss. ex Meisn. is synonymous with P. aucheri Boiss. The biogeographic importance of the so-called ‘Persian foothills’, and biodiversity conservation status of the area are discussed, together with distribution maps of 12 species. It is concluded that the majority of the endemic species in the southern and south-western parts of Iran are Irano–Turanian or have their origins in the Irano–Turanian region. Therefore, it is questionable to consider the area as part of either the Saharo–Sindian, Sudanian or Sudano–Zambezian regions. © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society, 2004, 146, 107–121. [ABSTRACT FROM AUTHOR]

Analyses were carried out ot identify boron (B) hyperaccumulating plant species in an actively B- mined area of Kirka, Eskişehir, Turkey. Only 4 plant species, Gypsophila sphaerocephala Fenzl ex Tchihat. var. sphaerocephala (Caryophyllaceae), Gypsophila perfoliata l. (Caryophyllaceae), Puccinellia distans (jacq.) Parl. subsp. distans (Gramineae) and Elymus elongatus (Host) Runemark subsp. turcicus (McGuire) Melderis (Gramineae), were identified in the highest b- containing sections of the mine. The species were found growing successfully under high total (8900 mg kg-1) and available (277 mg kg-1) soil B concentrations. Among these plant species, G. sphaerocephala contained considerably higher B concentrations in its above-gound parts (2093 ± 199 SD mg kg-1, seeds; 3345± 341 SD mg kg-1, leaves), compared to the roots (51 ± 11SD mg kg-1) and organs of the other species as revelaed by analyses using an ICP-AES (Varian, Vista model) instrument. This species was followed by G. perfoliata with respect to B concentrations in its various organs. This study shows that G. sphaerocephala was not only able to grow on heavily b-contaminated soils, but was also able to accumulate extraordinarily high concentrations of B. This provides a new plant genotype to explore the mechanism(s) of B hyperaccumulation which may lead to identifying the gene(s) conferring b-resistance and to phytomining of contaminated soils, especially where B-toxicity symptoms occur. To our knowledge, there are no reports available on the hyperaccumulation of B, although many reports are available on the phytoremediation of metalliferous soils that contain excess amounts of Zn, Mn,Cu, Co, Pb, al and Ni. [ABSTRACT FROM AUTHOR]

Pantoea agglomerans pv. gypsophilae ( Pag) causes root and crown gall disease on gypsophila, whereas P. agglomerans pv. betae ( Pab) induces the disease on beet as well as gypsophila. Both pathovars harbour a pathogenicity plasmid (pPATHPag or pPATHPab) that determines disease development. We have previously isolated and partially characterized a pleiotropic gene from the pPATHPag, designated as pthG, that encodes a virulence factor in gypsophila and an elicitor of a hypersensitive-like response in beet roots. The present study was undertaken to characterize pthG further as an avr gene. The infiltration of beet leaves with strains expressing PthG (i.e. Pag or Pab containing pthG in trans) caused an hypersensitive reaction (HR) response within 48 h, whereas strains lacking intact pthG (i.e. Pab or Pag mutated in pthG) resulted in gall formation after 5 days. A hypersensitive reaction was elicited by PthG on multiple beet species, whereas a marker exchange mutant of Pag in pthG extended its host range on these beet species. A marker exchange mutant of Pag in hrpJ, encoding a component of the Type III secretion system, prevented HR elicitation. Mutations in each of the hrp regulatory genes ( hrpY, hrpS and hrpL) substantially reduced the transcriptional activity of pthG in gypsophila cuttings. PthG could only be detected inside Pag cells during over-expression of hrpS or hrpL. Particle bombardment of GFP-PthG fusion caused cell death in beet, but not in non-host (melon) leaves. Present and previous results have established pthG as a broad-host-range avr gene that functions in multiple host plant species and the first functional avr gene in Pantoea spp. [ABSTRACT FROM AUTHOR]

Investigates a possible sex-differential pollen limitation at the flower level in the gynodioecious gypsophila repens infected by the smut fungus microbotryum violaceum. Comparison between open-pollinated and hand-pollinated flowers on the basis of fruit production and fecundity; Absence of sex-differential pollen limitation; Fruit and seed production and ovule number.

Within-population gene diversity (HS ) was estimated (using allozyme markers) for 16 populations of the perennial, outcrossing plant, Gypsophila fastigiata , on the Baltic island of Öland. The populations were characterized by data on extent, density, life-stages, and habitat diversity. Populations were classed as central or peripheral in relation to the distribution of “alvar” (habitats with shallow, calcareous soils on limestone bedrock) on southern Öland. Three minimal adequate models were used to explain HS and the proportions of juveniles and dead adults. In the first model, HS was significantly lower in peripheral populations and there were no significant additional effects of other explanatory variables. The lower diversity in peripheral populations can be explained by a combination of genetic drift (in populations that vary in size in response to habitat fragmentation) and lower levels of interpopulation gene flow than in central populations. In the two life-stage models, peripheral populations had significantly larger proportions of both juveniles and dead adults – indicating a greater demographic turnover than in the central populations. There were also significant effects of HS and species diversity on the proportion of juveniles. The central or peripheral position of populations is the strongest predictor of both within-population gene diversity and life-stage dynamics in Öland G. fastigiata . [ABSTRACT FROM AUTHOR]