Silene Conoidea Research Articles

First Report of the Molecular Mechanism of Resistance to Tribenuron-Methyl in Silene conoidea L.

Silene conoidea L. is an annual troublesome broadleaf weed in winter wheat fields in China. In recent years, field applications of tribenuron-methyl have been ineffective in controlling S. conoidea in Hebei Province, China. The aim of this study was to determine the molecular basis of tribenuron-methyl resistance in S. conoidea. Whole-plant response assays revealed that the resistant population (R) exhibited a higher level of resistance (382.3-fold) to tribenuron-methyl. The R population also showed high cross-resistance to other acetolactate synthase (ALS) inhibitors, including imazethapyr, bispyribac-sodium and florasulam. However, the R population could be controlled by the field-recommended rates of bentazone, MCPA, fluroxypyr, carfentrazone-ethyl and bromoxynil. In vitro ALS activity assays indicated that the tribenuron-methyl I50 value for the R population was 18.5 times higher than those for the susceptible population (S). ALS gene sequencing revealed an amino acid mutation, Trp-574-Leu, in the R population. Pretreatment with the P450 inhibitor malathion indicated that the R population might have cytochrome P450-mediated metabolic resistance. These results suggest that the Trp-574-Leu mutation and P450-mediated enhanced metabolism coexist in S. conoidea to generate tribenuron-methyl resistance. This is the first time that target-site and non-target-site resistance to tribenuron-methyl has been reported in S. conoidea.

Silene conoidea L.: A Review on its Systematic, Ethnobotany and Phytochemical profile

Silene conoidea L. is a weed commonly grown in subtropical and temperate zone of western Eurasia, and some part of Himalaya. S. conoidea is a small herb height from 20 to 40cm mostly grow as weed in different crops like wheat, barley, mustard, roquette and lentil pea. This is the first attempt to gather utmost information about the species distribution, taxonomy, ethno-medicines, phytochemical analysis, biological activity etc. of Silene conoidea. The present review aim was to collect fragmented information about the species in addition to explore its therapeutic importance in future research opportunities. A total of 100 research articles were reviewed using different sources like; Scopus, web of science, Science direct, google scholar and PubMed. The species are used as multipurpose in different biological activities against microbes, bacteria and as insecticidal. Silene is also important due to high contents of various chemicals compounds. Chemical extracts contain flavones, glycosides, saponins, sterols and glycosides. A research study shows that S. conoidea can be used as an indicator species of gold. Traditional therapeutic values of the species for treating respiratory, antioxidant, anti-diabetic and anticancer are needed to be validated through more research. Ethno-pharmacological and clinical trial research can be subjected for future studies.

Anti-Ache Benzylbenzofuran Derivatives from Silene conoidea

A new benzylbenzofuran, named 5′,7-dihydroxy-6-propenyl-2-(11′,12′-dimethylpyran)-benzylbenzofuran (1), and seven known benzylbenzofuran derivatives (2–8) were isolated from Silene conoidea L. for the first time. The structures of compounds 1–8 were identified by their spectral data and reference data. Compounds 1–8 were evaluated for anti-acetylcholinesterase (AChE) activities for the first time. Compounds 1, 2, 5, and 6 showed anti-AChE activities with IC50 values ranging from 12.55–85.43 μM.

Removal efficiency and mechanisms of formaldehyde by five species of plants in air-plant-water system

ABSTRACTThe foliar uptake and transport rates of formaldehyde as well as the abilities of leaf extracts to breakdown formaldehyde were investigated to discuss the formaldehyde removal efficiency and mechanism by five species of plants from air. Results showed that formaldehyde could be transported from air via leaves and roots to rhizosphere water. When exposed to 0.56 mg·m−3 formaldehyde, the formaldehyde removal rate ranged from 18.64 to 38.47 μg·h−1g−1 FW (fresh weight). According to the mass balance in the air–plant–water system, the main mechanism of the formaldehyde loss was its breakdown in plant tissues caused by both enzymatic reaction and redox reaction. Higher oxidation potentials of the leaf-extracts of Wedelia chinensis and Desmodium motorium corresponded well to higher abilities to breakdown added formaldehyde than other plants. Based on the different abilities of fresh and boiled leaf-extracts to dissipate formaldehyde, the enzymatic reaction in Chenopodium album L. was the dominant mechanism while the redox reaction in Kochia scoparia (L.) Schrad. and Silene conoidea L. was the main formaldehyde breakdown mechanism when exposed to low-level formaldehyde in air. The redox mechanism suggested that the formaldehyde removal may be increased by an increasing level of reactive oxygen species (ROS) induced by the environmental stress.

Germination Ecology of Catchfly (Silene conoidea) Seeds of Different Colors

ABSTRACT Catchfly (Silene conoidea), an annual herb, is usually recognized as an emerging weed species in Eurasia and North America. The presence of somatic seed polymorphism might aid in the adaptation of this weed in different climatic conditions. We conducted laboratory and greenhouse experiments to study the seed polymorphism and influence of various environmental factors like temperature, salt stress, osmotic stress and burial depth on the germination and emergence characteristics of catchfly. Optimum germination of seeds of all colors was recorded at a temperature of 15 oC. Germination of catchfly seeds of all colors followed decreasing trend as NaCl concentration increased from 50 mM to 200 mM. Seed germination was maximum (87-96%) at 0 MPa but gradually decreased to 40% as osmotic stress increases up to -0.4 MPa and completely inhibited at 0.6 MPa of all seed colors. A slight increase (from 60 to 95%) in the germination of seeds of black and dark brown colors was observed when seeding depth increased from 0 to 2 cm but decreased when seeding depth increased from 2 to 4 cm in seeds of all colors. There was no emergence of catchfly at seeding depth of 6 cm or greater. Our results concluded that catchfly seeds have the potential to germinate and emerge in various environmental conditions, but germination/emergence percentage of seeds of all colors will be different in different environmental conditions. Soil amendments including deep ploughing may aid for the successful management of this weed in cultivated areas.

Investigating past range dynamics for a weed of cultivation, Silene vulgaris.

Since the last glacial maximum (LGM), many plant and animal taxa have expanded their ranges by migration from glacial refugia. Weeds of cultivation may have followed this trend or spread globally following the expansion of agriculture or ruderal habitats associated with human‐mediated disturbance. We tested whether the range expansion of the weed Silene vulgaris across Europe fit the classical model of postglacial expansion from southern refugia, or followed known routes of the expansion of human agricultural practices. We used species distribution modeling to predict spatial patterns of postglacial expansion and contrasted these with the patterns of human agricultural expansion. A population genetic analysis using microsatellite loci was then used to test which scenario was better supported by spatial patterns of genetic diversity and structure. Genetic diversity was highest in southern Europe and declined with increasing latitude. Locations of ancestral demes from genetic cluster analysis were consistent with areas of predicted refugia. Species distribution models showed the most suitable habitat in the LGM on the southern coasts of Europe. These results support the typical postglacial northward colonization from southern refugia while refuting the east‐to‐west agricultural spread as the main mode of expansion for S. vulgaris. We know that S. vulgaris has recently colonized many regions (including North America and other continents) through human‐mediated dispersal, but there is no evidence for a direct link between the Neolithic expansion of agriculture and current patterns of genetic diversity of S. vulgaris in Europe. Therefore, the history of range expansion of S. vulgaris likely began with postglacial expansion after the LGM, followed by more recent global dispersal by humans.

Effects of pollination timing and distance on seed production in a dioecious weed Silene latifolia

Silene latifolia Poir. (white cockle or white campion) is an important invasive weed in North American agriculture. It exhibits dioecy, therefore, both male and female plants are required in order for seed production to occur. However, dioecious species being invasive is not common because of their limitations in pollination and subsequent seed production. The objective of this study is to determine the effect of pollination timing and distance on seed production of Silene latifolia. A series of experiments including pollination exclusion, timing and pollination distance were conducted in 2009 and 2010 at or around Saskatoon, Saskatchewan. For pollination exclusion, exclosures were built around the natural female plants for exclosure, sham-exclosure, and male and female combined treatments. Pollination timing was studied by applying exclosure, non-exclosure, night-exclosure, and day-exclosure treatments to individual female plants. Female plants were transplanted along a linear interval at six different distances from the pollen source to study the effect of pollination distance. S. latifolia was exclusively insect-pollinated and pollination occurred both day and night; however, in one year, pollination occurred mainly at night. Female plants that were in the range of 0–4 m from a compatible pollen source experienced no limitation to pollination. However, when the distance was increased further up to 128 m, pollination levels and subsequent seed production were declined. Moreover, there were differences in seed production between years suggesting that pollination was affected by the environmental conditions during pollination and the crop that white cockle was grown in. These experiments indicate that seed production in S. latifolia is limited by insect-pollination. Although there was pollination limitation for seed production at greater distances from a pollen source, the high fecundity rate (3000–18000 seeds per plant) resulted in a large seed output. Thus, we believe that a dioecious species may require characteristics that compensate the pollination limitation for a successful invasion.

A recurring syndrome of accelerated plastid genome evolution in the angiosperm tribe Sileneae (Caryophyllaceae)

In flowering plants, plastid genomes are generally conserved, exhibiting slower rates of sequence evolution than the nucleus and little or no change in structural organization. However, accelerated plastid genome evolution has occurred in scattered angiosperm lineages. For example, some species within the genus Silene have experienced a suite of recent changes to their plastid genomes, including inversions, shifts in inverted repeat boundaries, large indels, intron losses, and rapid rates of amino acid sequence evolution in a subset of protein genes, with the most extreme divergence occurring in the protease gene clpP. To investigate the relationship between the rates of sequence and structural evolution, we sequenced complete plastid genomes from three species (Silene conoidea, S. paradoxa, and Lychnis chalcedonica), representing independent lineages within the tribe Sileneae that were previously shown to have accelerated rates of clpP evolution. We found a high degree of parallel evolution. Elevated rates of amino acid substitution have occurred repeatedly in the same subset of plastid genes and have been accompanied by a recurring pattern of structural change, including cases of identical inversions and intron loss. This “syndrome” of changes was not observed in the closely related outgroup Agrostemma githago or in the more slowly evolving Silene species that were sequenced previously. Although no single mechanism has yet been identified to explain the correlated suite of changes in plastid genome sequence and structure that has occurred repeatedly in angiosperm evolution, we discuss a possible mixture of adaptive and non-adaptive forces that may be responsible.

The isolation of microsatellite markers for the study of genetic diversity in Silene conoidea

The isolation of microsatellite markers for the study of genetic diversity in Silene conoidea

Meiotic Studies in Some Members of Caryophyllaceae Juss. From the Western Himalayas

The paper reports meiotic studies on 50 populations comprising 12 species belonging to 5 genera of Caryophyllaceae from the Western Himalayas. The chromosome numbers in Arenaria kashmirica (n=20), Silene conoidea (n=20), S. edgeworthii (n=12 and n=24), S. moorcroftiana (n=24), S. nepalensis (n=12), Stellaria media (n=13), S. monosperma (n=13) and S. semivestita (n=13) are reported for the first time. The chromosome numbers in Lychnis coronaria (n=12) and Silene vulgaris (n=24) are given for the first time from India, along with Gypsophilla ceratioides (n=15) from the Western Himalayas. The course of meiosis varies from normal to abnormal in different populations of Silene conoidea, S. edgeworthii, S. vulgaris, Stellaria media, S. monosperma and S. semivestita. The course of meiosis was abnormal in all studied populations of Lychnis coronaria. Abnormal microsporogenesis (cytomixis, chromosomal stickiness, unoriented bivalents, formation of laggards and bridges) led to reduced pollen fertility and differences in pollen grain size.

Effects of cultivation regimes on weed community structures in newly reclaimed sandy farmlands

The varieties, quantities, coverage rates and heights of farmland weeds were surveyed and species diversity and richness analyzed in a newly reclaimed sandy farmland located in the margin oasis of the middle reaches of Heihe River Basin, Northwest China. The aim of the study was to evaluate the effects of cultivation regimes on weed community structure characteristics in the basin. A total of 16 weed species from 10 families were identified and recorded. The most common species of weed communities in newly reclaimed sandy farmlands are Chenopodium album, Eleusine indica, Setaria viridis and Amaranthus retroflexus. Weed community compositions are largely influenced by cultivation regimes. Weed species richness, Shannon-Wiener index and Simpson in-dex are lower in conventional cultivation regimes (film mulching, autumn plowing and continuous maize planting). Those could, however, be improved under straw mulching, zero-autumn plowing and maize-soybean rotation treatments. Compared with film mulching, E. indica has a higher dominance ratio while C. album and A. retroflexus have lower dominance ration under straw mulching treatments. Compared with autumn plowing, S. viridis, A. reteroflexus, Silene conoidea and C. glaucum have a higher dominance ratio whereas E. indica has a lower dominance ratio under zero-autumn plowing treatments. Also compared with con-tinuous maize planting, S. conoidea exhibits a higher dominance ratio under maize-soybean rotation regimes. There exist random rare weed species distribution in the field, which are not significantly effected by cultivation regimes. Results further show that weed species is few and weed communities composition is single in a newly reclaimed sandy farmland, and cultivation regimes obviously influence weed species diversity and community structure in reclaimed sandy farmlands. It is recommended to conduct additional research for a non-subjective interpretation of the effects of cultivation regimes on weed growth in order to guide weed control in newly reclaimed sandy farmlands.

Experimental crosses within EuropeanSilene latifolia(Caryophyllaceae): intraspecific differentiation, distance effects, and sex ratio

The dioecious weed Silene latifolia Poiret is thought to have spread northwards through Europe from separate southern source populations and shows a pronounced east–west pattern of differentiation in seed morphology. We used crossing experiments to investigate whether patterns of interfertility in S. latifolia are consistent with a scenario of ongoing speciation (reflected by outbreeding depression in crosses between the seed races), a scenario involving local inbreeding (reflected by heterosis in interpopulations crosses), or a combination of both scenarios. The experiments involved three western and three eastern populations, which were crossed reciprocally in all possible inter- and intra-population combinations. Inter-race cross-progenies did not have lower fitness than those from intra-racial crosses, and the results are not consistent with a scenario of incipient speciation. A pattern of overall heterosis was found in three variables, indicating the expression of inbreeding depression in progeny from intrapopulation crosses. For two fitness variables, negative relationships between interpopulation distance and heterosis, together with signs of outbreeding depression in the longest-distance crosses, suggest that there may be significant levels of genetic differentiation between geographically distant populations. The sex ratio was female-biased in most progenies, especially in those from the longest-distance crosses.

Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon?

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species--the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener.

Two New C-Glycosylflavones From Silene Conoidea

The butanol-soluble part of the methanolic extract of Silene conoidea afforded two new flavone glycosides having C-C linkage between C-8 and C-1″: 8-C-(4″-O-α-L-rhamnopyranosyl)-β-D-glucopyranosyldiosmetin (1) and 8-C-(4″-O-α-L-rhamnopyranosyl)-β-D-glucopyranosylapigenin (2). Both the glycosides were purified by HPLC and characterized spectroscopically. In addition to 1–2, α-spinasterol (3) and its giucoside (4) have also been reported for the first time from the investigated source.

Phenotypic Changes in Host Plants Diseased by Microbotryum violaceum: Parasite Manipulation, Side Effects, and Trade-offs

Parasites induce changes in their hosts that can be viewed either as pathological effects of infection (i.e., symptoms), adaptive defense by the host, or adaptive manipulation on the part of the parasite. The pollinator-borne anther-smut fungus Microbotryum violaceum is a prevalent parasite of the common roadside weed Silene latifolia (Caryophyllaceae). The fungal disease alters the phenotype of the host plant in several important ways. In a greenhouse experiment, we show that the disease accelerated flowering and that diseased plants invested relatively less in root biomass than did healthy plants. In a second experiment, diseased plants also produced smaller, more irregularly shaped flowers with different nectar-sugar production than did healthy plants. The magnitude of some of these effects of the disease differed for different fungal crosses. Differential alteration of host phenotype may result in pollinator-mediated selection on this pathogen. Whereas some of these changes in host phenotype may represent parasite adaptations, others may represent side effects of disease. It also appears that although the parasite modifies host phenotypes, trade-offs become evident, such as those between flower size and flower number and investment to vegetative compared with storage biomass. This indicates that this fungus cannot produce a plant phenotype optimal for pollinator attraction and disease transmission.

Can the spread of agriculture in Europe be followed by tracing the spread of the weed Silene latifolia. A RAPD study

On the basis of gene frequency data of three flavone glycosylating genes, populations of the agricultural weed Silene latifolia (Caryophyllaceae) in Europe can be divided into two chemical races: an eastern and a western race. Morphological data also show a clear east-west division. When the two datasets are combined at least nine different geographical races can be distinguished using cluster analysis. Because these observations are hard to explain by selection, it has been proposed that these different races probably originated as a consequence of migration during the spread of agriculture over Europe in the past. To discriminate between selection and genetic drift many more selectively neutral easy-to-score characters are needed. In order to test whether random amplified polymorphic DNAs (RAPDs) might be suitable for this purpose, we performed a small-scale RAPD analysis on 16 geographical different populations. Using Jaccard's coefficient of similarity, we calculated genetic distances by pair-wise comparisons of both unique and shared amplification products, and a dendrogram was subsequently constructed using an unweighted pair-group method with arithmetical averages (UPGMA). On the basis of the dendrogram two clusters were discerned that clearly coincide with the aforementioned east-west division in populations. As there has been little or no artificial selection on this weed, its migration routes may be a good reflection of the different geographical routes agriculture has taken. We propose that a phylogenetic analysis of RAPD data of many more populations may provide additional information on the spread of agriculture over Europe.

Can the spread of agriculture in Europe be followed by tracing the spread of the weed Silene latifolia. A RAPD study

Can the spread of agriculture in Europe be followed by tracing the spread of the weed Silene latifolia. A RAPD study

A potexvirus isolated from Silene pratensis.

A potexvirus, silene virus X (SVX), was isolated from the weed Silene pratensis. Infectious preparations contained nucleoprotein rods predominantly 546 nm in length, consisting of a 6.9-kb polyadenylated single-stranded RNA and a 29-kd capsid protein. Double-stranded RNAs of 17.1, 7.0, 5.7, and 4.6 kbp were isolated from SVX-infected plants. In vitro translation products of SVX single-stranded or denatured double-stranded RNAs reacted with SVX antiserum. Hybridization studies with SVX cDNAs showed no nucleotide homology with seven other potexviruses. The virus is more closely related serologically to narcissus mosaic virus than to nine other potexviruses.

Selenium in soils and plants of the Jordan Valley

The selenium (Se) content of plants and soils in the northern part of the Jordan Valley, a semi-arid region, was determined by a fluorometric method. Leguminosae, Gramineae, and Cruciferae were found to contain the highest amounts of Se. Of the Leguminosae, Alhagi maurorum contained 4·70 μg Se/g and Prosopis farcta from the north end of the Dead Sea and North Shunah contained 0·55 and 600 μg Se/g, respectively. Of the Gramineae, Cynodon dactylon, Hordcum spontaneum , Setaria verticillata, and Sorghum halepense contained 0·08 to 4·0, 5·26, 10·48 and 3·44 μg Se/g, respectively. Sinapsis alba (Cruciferae) contained 12·67 μg Se/g. Other families found to have less than 1 μg Se/g are represented by Chenopodium murale (Chenopodiaceae) and Silene conoidea (Caryophyllaceae). The Se content of C. dactylon was positively correlated with total Se in the soil. The water-soluble Se in the soils was 0·0025 μg/g (pH 8·01–8·12) around the Dead Sea and 0·107 μg/g (pH 7·60–7·80) in North Shunah. The corresponding average total Se was 1·115 and 4·043 μg/g in these two locations, respectively.

New Starches. VII. The Properties of the Starch from Silene conoidea

New Starches. VII. The Properties of the Starch from Silene conoidea