Senecio Vulgaris Research Articles

Effects of SvAPETALA1-5 gene on floral organ development in Senecio vulgaris.

Asteraceae is a large class of eudicots with complex capitulum, and little is known regarding the molecular regulation mechanism of flower development. APETALA1(AP1) belongs to the MADS-box gene family and plays a key role in plant floral induction and floral organ development. In this study, the bioinformatics and tissue-specific expression of AP1 homologous gene SvAP1-5 in Senecio vulgaris were analyzed. Based on VIGS technology, SvAP1-5 gene silencing plants were created, and SvAP1-5 was overexpressed in Solanum nigrum. The results of bioinformatics analysis showed that SvAP1-5 gene had typical MADS-box and K-box structure, and contains FUL motif and paleoAP1 motif at the C-terminal. SvAP1-5 belongs to the euFUL branch of AP1 gene. qRT-PCR results showed that SvAP1-5 was expressed in bracts, petals and carpels, and was highly expressed in carpels. Compared with the control group, SvAP1-5 gene silencing resulted in irregular petal dehiscence, increased stigma division, and carpel dysplasia. The fruit development of SvAP1-5 overexpressing S.nigrum plants was abnormal, and the hyperplastic tissue similar to fruit appeared. In summary, SvAP1-5 gene may be involved in the development of petals and carpels and plays an important role during the development of S.vulgaris.

Assessing landscape disturbance in Donbass using phytomonitoring data

The article presents the results of a long-term experimental monitoring (1996-2023) of the condition of indicator plants has been implemented in the territory of Central Donbass. Due to the experiment, it was proved that flowering plants have both indices of non-plasticity in the structure of vegetative and generative parts. Indicator species analyzed: Centaurea diffusa Lam., Cichorium intybus L., Diplotaxis muralis (L.) DC., Echium vulgare L., Reseda lutea L., Senecio vulgaris L. and others. Registration sites with priority pollutants and complex pollution have been established. It was found that the geostrategic pattern obtained by mapping for traits on embryotic teratogenesis and morphological heterogeneity of indicator plants coincide on 93% of the projective coverage area. It was found out that for the period 1996-2013, 32% of the total investigated area of the Central Donbass was technogenically transformed, for the period 2014-2021, this indicator was 36%, and for 2022-2023, 41%.

Evaluation of the thermal stability and transfer rate of pyrrolizidine alkaloids during the brewing of herbal infusions contaminated with Echium vulgare and Senecio vulgaris weeds

Pyrrolizidine alkaloids (PAs) are currently in the spotlight of food safety due to the potential health risk that their intake may entail for consumers. Among the wide variety of food products likely to be contaminated with PAs, teas and herbal teas stand out because of their cross-contamination with weeds from PA-producing plants. Accordingly, this work simulates the cross-contamination of chamomile tea samples with weeds of Senecio vulgaris and Echium vulgare to evaluate the effect of brewing on the PA content at different temperature (100 and 75 °C) and time (5 and 10 min) conditions. The results of the thermal degradation study revealed PAs are quite stable compounds under the conditions assayed, being the initial PA concentration the variable that strongly affected the thermal stability of these compounds, rather than the brewing temperature and time. On the other hand, it was confirmed that not all PAs are effectively transferred from the dry material to the infusion during the brewing process, leading to overall transfer rates between 13 ± 1 to 87 ± 10%. Also, it was observed that the extraction efficiency may be influenced by the type of matrix, since transfer rates were lower when the PA migration came from Echium vulgare than from Senecio vulgaris. Moreover, it was confirmed that the real content of PAs in a cup of tea can be overestimated in 2–7 times if their transfer rate is not considered during the brewing process, highlighting the importance of analyzing the infusion samples instead of the dry tea samples to correctly assess the risk exposure of consumers to these contaminants.

First Report of Puccinia lagenophorae on Senecio vulgaris in Pennsylvania.

Common groundsel (Senecio vulgaris L.), is an aster native to Eurasia and is now a common weed in gardens, roadsides and vacant lots worldwide. In 2001, Scholler and Toike were first to report that common groundsel was a host for the rust fungus Puccinia lagenophorae Cooke in North America (Scholler and Toike 2001). This report from California was followed by reports of P. lagenophorae infections on common groundsel in New York, Oklahoma, and Oregon (Little-field et al. 2005). In 2007, Bruckart et al. published the first report of this host-pathogen combi-nation in Canada (Bruckart et al. 2007). To our knowledge, there are no published reports of P. lagenophorae on common groundsel in Pennsylvania (Farr and Rossman 2022). In May 2022, symptomatic common groundsel plants were observed in Biglerville, Adams Co., southern Penn-sylvania (N 39.9268047, E 77.2473878). Host plants exhibited conspicuous aecia on deformed stems (Fig. 1). Disease symptomology and morphology were consistent with P. langenophorae (Scholler and Toike 2001). P. lagenophorae is an autoecious rust that forms aecia and telia, but only aecia are typically formed on Senecio spp.; telia were not noted during our observations. Aecia were orange, cup-shaped, bordered by fragmented recurved peridia (Fig. 1), and they had mean diameters 262.9 ± 20.9 X 175.2 ± 22.2 μm (n = 20). Aeciospores were orange, oval, with mean diameters of 16.5 ± 0.97 X 11.5 ± 1.08 μm (n = 20). Fungal DNA was extracted from symptomatic stems. Polymerase chain reaction and sequencing of the 28S region of the nuclear ribosomal DNA repeat were conducted with primers Rust2inv and LR6 following protocols in Aime (2006). The sequence shared 100% identity (909 / 909 bp) with 8 sequences of P. la-genphorae in GenBank, including one on Ozothamnus cordatus from Perth, Western Australia, Australia (KF690699), vouchered in the Queensland Plant Pathology Herbarium (BRIP 57770), Brisbane, Queensland, Australia. A voucher specimen has been preserved in the Arthur Fungari-um at Purdue University (PUR N24039) with corresponding 28S sequence (GenBank accession OP718536).

Edaphic ecotypic divergence in Senecio vulgaris and the evolutionary potential of predominantly self-fertilising species

ABSTRACT Background There is continued interest in ecotypic divergence because it is informative of local adaptation and can be an important step in speciation. Aim To investigate ecotypic divergence in a predominantly self-fertilising species, Senecio vulgaris, in response to variation in soil nitrogen (N) and phosphorus (P) concentrations. Methods Responses to increased N and P were compared among populations sampled from sand dune, bird sanctuary and garden habitats, containing soils of low, high and intermediate fertility, respectively. Responses were measured in terms of growth, with capitulum production and days to seed set recorded in some experiments. Results Population differences in response to increased N and P were detected and linked to differences in soil fertility among habitats. Thus, the sand dune population exhibited the lowest growth response to increased N and P concentrations, while a bird sanctuary population showed the greatest response to increased N supplied as either NaNO3, NH4NO3 or urea. Genetic variation in response to increased N was present in both of these populations. Conclusions The results indicate the presence of edaphic ecotypes in S. vulgaris, providing further evidence that questions the premise that self-fertilisation limits adaptation to environmental change and thus is an evolutionary dead-end.

Cytotoxicity and Genotoxicity of Senecio vulgaris L. Extracts: An In Vitro Assessment in HepG2 Liver Cells.

Senecio vulgaris L. is a herbaceous species found worldwide. The demonstrated occurrence of pyrrolizidine alkaloids in this species and its ability to invade a great variety of habitats result in a serious risk of contamination of plant material batches addressed to the herbal teas market; this presents a potential health risk for consumers. In light of the above, this work aimed to assess the cytotoxic and genotoxic activity of S. vulgaris extracts in HepG2 cells. Dried plants were ground and extracted using two different methods, namely an organic solvent-based procedure (using methanol and chloroform), and an environmentally friendly extraction procedure (i.e., aqueous extraction), which mimicked the domestic preparation of herbal teas (5, 15, and 30 min of infusion). Extracts were then tested in HepG2 cells for their cytotoxic and genotoxic potentialities. Results were almost superimposable in both extracts, showing a slight loss in cell viability at the highest concentration tested, and a marked dose-dependent genotoxicity exerted by non-cytotoxic concentrations. It was found that the genotoxic effect is even more pronounced in aqueous extracts, which induced primary DNA damage after five minutes of infusion even at the lowest concentration tested. Given the broad intake of herbal infusions worldwide, this experimental approach might be proposed as a screening tool in the analysis of plant material lots addressed to the herbal infusion market.

Аномалии эмбриональных структур растений-индикаторов Донбасса

Examples of atypical structure of the embryonic apparatus of indicator plants in the Donbas are highlighted. Many years of experience in conducting phytoindication experiments (1998–2022) made it possible to identify accounting sites with contrasting geochemical characteristics and monodominant ingredient pollution. Registered abnormalities are considered as variants of extreme structural polymorphism of plants of natural flora under conditions of specific stress of the technogenic environment. For phytotesters Amaranthus retroflexus L., Atriplex patula L., Capsella bursa-pastoris (L.) Medik., Diplotaxis muralis (L.) DC., Polygonum aviculare L., Reseda lutea L. and Senecio vulgaris L. integral indicators of the state of generative systems (2019–2021) were calculated according to the structure of pollen, the frequency of occurrence of teratological manifestations in the embryonic apparatus and successful seed germination. Examples of specific manifestations of degradation and neoplasms in the structures of plant embryonic tissues are given. The morphological experiment was implemented in the ascertainment of contrasting levels of dominant pollutants, which makes it possible to recommend specific features of plant structure as markers for ecological monitoring of natural environments. An assumption about the influence of individual tissue transformations in germinal structures on the quality of seed material in general and on the methods of formation of adaptive heterospermia was made.

Aphids and Mycorrhizal Fungi Shape Maternal Effects in Senecio vulgaris.

Plant performance in any one generation is affected not only by the prevailing environmental conditions, but also by the conditions experienced by the parental generation of those plants. These maternal effects have been recorded in a many plant species, but the influence of external biotic (as opposed to abiotic) factors on shaping maternal effects have been rarely examined. Furthermore, almost all previous studies have taken place over one plant generation, rather than across multiple generations. Here, we studied the influence of insect herbivory and arbuscular mycorrhizal (AM) fungal colonisation on the shaping of maternal effects in the annual forb Senecio vulgaris. We grew plants with and without aphids (Myzus persicae) and AM fungi (hereafter termed ‘induction events’) over four successive generations, wherein seeds from plants in any one treatment were used to grow plants of the same treatment in the next generation, all in identical environmental conditions. We found strong evidence of maternal effects in the second plant generation, i.e., after one induction event. These plants took longer to germinate, flowered in a shorter time, produced lighter seeds and were shorter and of lower biomass than their parents. Aphid attack tended to enhance these effects, whereas AM fungi had little influence. However, thereafter there was a gradual recovery in these parameters, so that plants experiencing three inductions showed similar life history parameters to those in the original generation. We conclude that experiments investigating maternal effects need to be performed over multiple plant generations and that biotic factors such as insects and mycorrhizas must also be taken into account, along with abiotic factors, such as nutrient and water availability.

Functional analysis of flower development related gene SvGLOBOSA from Senecio vulgaris.

The unique capitulum of Asteraceae has important ornamental and research value. Few studies have described the complex molecular mechanism of flower development. In this study, SvGLOBOSA(SvGLO), the MADS-box gene of Senecio vulgaris, was identified by screening the transcriptome data, and its function was examined. The gene structure was analyzed and its function was predicted through bioinformatics. The relative expression levels in different tissues of wild-type S. vulgaris were analyzed by qRT-PCR. SvGLO was overexpressed in Solanum nigrum and morphological observations were made. Histological staining was used in analyzing the histological changes in the ovary of transgenic S. nigrum. The results showed that the open reading frame of SvGLO was 591 bp long, encoding 196 amino acids. It has typical MADS-box and K-box domains and contains a PI motif at the C-terminal. SvGLO belongs to the PI/GLO subfamily of class B MADS-box genes. qRT-PCR results showed that SvGLO was highly expressed in inflorescence tissues but not in vegetative organs. In SvGLO-overexpressed S. nigrum, the sepals showed some characteristics of petals, carpels transformed into stamen-like organs, and fruit development was abnormal. Histological staining revealed that the morphology of ovary wall cells of transgenic S. nigrum was similar to that of anther wall cells of the stamen of wild-type S. vulgaris. Therefore, SvGLO may be involved in the regulation of petal and stamen development in S. vulgaris.

Plant DNA barcoding and metabolomics for comprehensive discrimination of German Chamomile from its poisonous adulterants for food safety

German Chamomile (Matricaria recutita L.) is one of the most consumed herbal teas in the world. Deliberate and undeliberate adulteration in German Chamomile raw material represents serious concerns for consumers’ safety. Authentication of Matricaria recutita L. samples was performed using an integrative approach of DNA barcoding and chemical profiling. Discrimination of M. recutita from three morphologically related species namely Anthemis cotula L., Senecio desfontainei Druce and Senecio vulgaris L. was accomplished. Three plastid loci (mat K, rbcL and psbA-trnH) and two nuclear spacers (ITS and ITS2) were utilized for the DNA barcoding of M. recutita. The Chemical profiling of M. recutita was achieved using untargeted HPTLC-image analysis. Among the tested barcoding loci, ITS2 revealed the maximum genetic diversity among the studied plants. ITS2 showed adequate polymorphic sites to detect interspecific variation with high amplification and sequencing success. Chemical profiling showed that flavonoids, coumarins, sesquiterpene lactones and phenolic acids are the main secondary metabolite classes of the candidate plants. While, flavonoids and phenolic acids served as quality markers, sesquiterpene lactone (anthecotulide) and pyrrolizidine alkaloid (senecionine) accounted as toxicity markers for the adulterants. Notably, coumarin accumulation pattern could be utilized to discriminate M. recutita from its adulterants due to the absence of hernarin and umbelliferone from Senecio species. The results of this study suggest that, integrating genetic and metabolomic fingerprinting could serve as an effective tool, with 100% success rate, in authenticating M. recutita and discriminating its samples from the morphologically related toxic adulterants. This offers a comprehensive tool for the quality control of M. recutita samples in food industry.

Phytotoxicological study of selected poisonous plants from Azad Jammu & Kashmir.

Poisonous plants cause tremendous economic losses to the livestock industry. These economic losses are deterioration in their health, decreased productivity, deformed offspring, and reduced longevity. The current study is the first comprehensive report on poisonous plants of Azad Jammu and Kashmir which systematically documents the phytotoxicological effect and mode of action in livestock. The information was gathered from 271 informants including 167 men and 104 women through semi-structured interviews and literature search through available databases. The data collected through interviews was analyzed with quantitative tools viz. the factor informant consensus and fidelity level. A total of 38 species of flowering plants belonging to 23 families and 38 genera were reported. Family Asteraceae (5 spp) was the most dominant, followed by Solanaceae (4 spp), Fabaceae (4 spp), Euphorbiaceae (4 spp) and Convolvulaceae (3 spp). Among all the species collected, herbs were the dominant life form (22 spp, 57.89%), trailed by shrubs (11 spp, 28.95%), and trees (5 spp, 13.16%). Whole plant toxicity was reported to be the highest (15 spp, 39.47%), followed by leaf toxicity (12 spp, 31.58%), seed toxicity (4 spp, 7.89%), fruit toxicity (3 spp, 10.53%), latex toxicity (2 spp, 5.26%), flowers toxicity (1 spp, 2.63%), and berries toxicity (1 spp, 2.63%). The most toxic route of administration was found oral (39 spp, 40.63%), followed by intraperitoneal (24 spp, 25%), and intravenous (21 spp, 21.88%). The most commonly affected organ was found liver (20.41%), followed by gastrointestinal tract (20.341%), CNS (16.33%), skin (14.29%), kidneys (12.24%), lungs (4.04%), reproductive organs (2.04%), spleen (1.75%), blood (1.75%), heart (1.75%), urinary tract (1.75%), and pancreas (1.75%). The maximum Fic value was found for dermatological disorders (0.91), followed by the endocrine system (0.90), gastrointestinal (0.82), neurology (0.77), nephrology (0.67), cardiovascular (0.67), urinary (0.67), respiratory (0.60), sexual (0.60) disorders. Senecio vulgaris, and Ageratum conyzoides were the most important plants with fidelity level (0.95) and (0.87). Nerium oleander, Lantana camara, Leucaena leucocephala, and Ricinus communis were the important poisonous plant with maximum fidelity level (100%). Ricinus communis with reported lowest LD50 (<20 mg/kg) was the top-ranked poisonous plant followed by Lantana camara and Justicia adhatoda (25–50 mg/kg), Nerium Oleander (157.37 mg/kg), and Datura innoxia (400 mg/kg). We found that knowledge about poisonous plants is less prevailing in the rural areas of Azad Kashmir compared to the knowledge about medicinal plants and poisonous nature of reported plants is due to production of toxic substances and presence of essential oils.

Selection of URBANIZATION Indicator Species Through Naturalized Plant Distribution Analysis

Purpose: As the number of foreign plants adapted to the urban environment increased, urban plants that could grow and adapt to the city appeared. These plants invade the existing ecosystem and provide direct and indirect risk factors to plants and humans, such as vegetation disturbance in nature and cities and pollen allergy. This study is expected to be used as a standard for urbanization indicators by selecting indicator species through distribution analysis of naturalized plants. Method: This study was analyzed based on flora survey data for 12 years from 2006 to 2017, the 3rd to 4th National Natural Environment Survey period, including 1200 places(776 map index system num-bers). For distribution analysis of naturalized plants, matrix analysis was applied. The researchers ana-lyzed the number of species by frequency of appearance in 162 cities and counties and the number of species by frequency of appearance in 1200 places. In addition, this study classified the distribution grades by the matrix analysis and tried to select the urbanization indicator species by conducting the first and second stages of evaluation. Results: As a result of the second stage evaluation, 34 species were selected. There were 28 species with grades 2 to 3 in the distribution grade. There were 6 species with a naturalization rate of 15% or more and an appearance rate of 40% or more. Species with an urbanization index of 15% or more and an appearance rate of 40% or more were analyzed as 15 species. As a result of synthesizing the evaluation items, researchers selected 6 species as urbanization indicators species. Conclusion: The urbanization indicator species had a low distribution grade, and they had a high fre-quency of appearance in 17 administrative districts. Researchers selected species of high appearance rates in areas with high naturalization rates and species of high appearance rates in regions with high urbanization indexes. As a result, 6 species were selected, including Juncea, Supina, Coccinea, Great rag-weed, Common groundsel, and Asper.

Reciprocal interactions between aphids and arbuscular mycorrhizal fungi across plant generations

The conditions experienced by one plant generation can influence the growth of the offspring generation. These maternal effects can reduce performance of foliar-feeding insects, through accumulation of plant defences. Arbuscular mycorrhizal fungi (AMF) inhabit the roots of plants and are known to influence the performance of foliar-feeding insects. However, all published studies of the interactions between insects and AMF have taken place within one plant generation, but none across generations. Thus, in the present study, Senecio vulgaris plants were grown with or without aphids and AMF (termed ‘induction events’), and seeds from each treatment were used to grow plants experiencing that same treatment over four successive generations, all grown in identical environmental conditions. Naïve aphids were reared on Senecio plants whose parents had experienced 0, 1, 2 or 3 induction events. We found strong negative maternal effects of herbivory on aphid growth, which were not mitigated by the mycorrhiza. However, teneral weight and growth rate showed a gradual recovery; aphids reared on plants whose previous three generations suffered attack were similar in size to those at the beginning of the study. Herbivory had positive or negative effects on the mycorrhiza, dependent upon the number of previous generations suffering attack or having mycorrhizal associations. We conclude that the outcome of many insect plant fungal experiments is likely to have been influenced by and need to account for maternal effects of the parental plant’s growth conditions.

Global Warming Could Magnify Insect-Driven Apparent Competition Between Native and Introduced Host Plants in Sub-Antarctic Islands.

Pristine sub-Antarctic islands terrestrial ecosystems, including many endemic species, are highly threatened by human-induced cosmopolitan plant invasion. We propose that native plant suppression could be further facilitated by the subsequent invasion by generalist pest species that could exacerbate their competitive exclusion through the process of apparent competition. By comparing the biological parameters of an invasive aphid species, Myzus ascalonicus, on one native (Acaena magellanica) and one invasive (Senecio vulgaris) plant species, we showed that survival and fecundity were higher and development time lower on the native plant species than on the invasive one. Moreover, comparing the effect of a temperature increase on the population dynamics of M. ascalonicus on the two plants, we showed that the relative profitability of the native species is further amplified by warming. Hence, while pest population doubling time is 28% higher on the invasive plant under current temperature, it would become 40% higher with an increase in temperature of 3°C. Consequently, our findings demonstrate that global warming could exacerbate competitive exclusion of native plants by invasive plants in sub-Antarctic islands by its indirect effect on the apparent competition mediated by generalist phytophagous pests.

Morphological and genetic diversity of Senecio vulgaris L. (Asteraceae) in Iran

Senecio vulgaris L., an annual herb belonging to the Asteraceae, is widely distributed in different regions of the world. There is no information on the intraspecific variations of the morphological and molecular features of this species. In the present investigation, we studied the morphological and genetic diversity of 81 accessions of S. vulgaris collected from 10 geographical populations. Eleven inter simple sequence repeat (ISSR) primers were used for the examination of genetic variations among the populations. Analysis of molecular variance (AMOVA) and GST analyses revealed significant differences among the investigated populations. A significant correlation between genetic distance and geographical distance was revealed by the Mantel test. However, reticulation analysis indicated the occurrence of gene flow among most of the populations studied. Principal component analysis (PCA) plot showed that the number of capitula, length of the cauline leaf and plant height were the most variable morphological characters. Principal coordinates analysis (PCoA) plot revealed two groups of populations, according to molecular and morphological data. The results suggested the existence of possible intraspecific taxonomic ranks within this species.

Identification and Simultaneous Determination of the Main Toxical Pyrrolizidine Alkaloids in a Compound Prescription of Traditional Chinese Medicine: Qianbai Biyan Tablet.

Qianbai biyan tablet (QT) is a compound prescription of traditional Chinese medicine which is used to treat nasal congestion, rhinitis, and nasosinusitis, with Senecio scandens as its main plant material. Several pyrrolizidine alkaloids (PAs) were reported in Senecio scandens and others of Senecio species. Although Senecio scandens is assigned as the legal plant material of QT, whether replaced use of it by other Senecio plants can bring toxicity is unknown because of the lack of quantitative data about toxic PAs between different Senecio species. In the present study, adonifoline, senkirkine, and another PA presumed as emiline have been identified in QT; however, there was no senecionine detected in all tablets. PA contents in QTs varied in different companies and different batches. Adonifoline existed only in Senecio scandens, and senecionine was detected in all eight Senecio plants investigated in the present study. Data showed that replaced use of Senecio scandens with a low level of senecionine by other Senecio plants such as Senecio vulgaris containing a high level of senecionine is advertised to be forbidden. Data of the present study may be used as a reference to make new drug quality regularity and recommendation guideline for the safety of QT.

Effects of latitudinal variation on field and common garden comparisons between native and introduced groundsel (Senecio vulgaris) populations

Abstract Aims Field and common garden comparisons are commonly performed to test the rapid evolution of increased vigor in introduced plant populations. Latitudinal clines in phenotypic traits can obscure such evolutionary inferences, particularly when native or introduced populations are distributed across large geographic ranges. We tested whether the latitudinal clines influence comparisons between introduced and native populations of Senecio vulgaris. Methods Senecio vulgaris is native to Europe but has been introduced in northeastern and southwestern China. To evaluate the performance in terms of growth and reproduction between native European populations and introduced Chinese populations, we compared plant height, number of branches and number of capitula in field populations in native and introduced ranges and in a common garden in Switzerland. Important Findings The introduced Chinese populations performed better than the native European populations in the field in terms of plant height and number of capitula, which was consistent with the prediction of the evolution of the increased competitive ability (EICA) hypothesis. The Chinese populations produced more capitula than the European populations when the latitudinal cline was considered in the common garden comparison. When we compared the traits of the northeastern Chinese, southwestern Chinese and European populations in both the field and common garden, the northeastern Chinese populations, at latitudes similar to those of the European populations, exhibited greater plant size and more capitula than the European populations in both the field and common garden. However, the southwestern Chinese populations, at latitudes much lower than those of the European populations, did not perform better than the native populations in terms of reproduction. In conclusion, our results suggest that latitudinal clines in phenotypic traits should be considered in field and common garden comparisons when introduced populations are geographically structured.

ФИТОТЕСТИРОВАНИЕ ЗАГРЯЗНЕНИЯ ТЯЖЁЛЫМИ МЕТАЛЛАМИ ПОЧВ ДОНБАССА

The article presents the results of phytotesting of soil solutions with high concentrations of heavy metal ions. The sensitivity of Donbass species plant to soil pollution was established by specific transformations in the structures of the embryonic root Achillea nobilis L., Artemisia vulgaris L., Centaurea diffusa Lam., Galinsoga parviflora Cav., Senecio vulgaris L., Tripleurospermum inodorum (L.) Sch. Bip. Model experiments on plant germination were carried out in laboratory conditions with fixed concentrations of individual metals and with joint pollution, as well as when testing soil samples taken in the zones of influence of industrial facilities of Don-bass.

STATUS OF HERBICIDE RESISTANCE IN WEEDS AND THE WAYS TO MITIGATE IT FROM GLOBAL PERSPECTIVE

Survivability of a few plants with natural resistance after herbicide application and their reproduction followed by herbicide application on each successive generation results in herbicide resistance and this phenomenon is rampant in present day agricultural fields. The study design is thus, focused on the overall status of herbicide resistance weeds and their distribution, mechanism of herbicide resistance in weed biotypes and the practices that are adopted and need to be adopted in order to curb the resistance development mechanism. The first herbicide resistance evidence was identified in triazine resistant to common groundsel (Senecio vulgaris). However, herbicide resistance was reported against 2,4-D from Hawaii as early as 1957. Currently, 512 unique cases (species×site of action) of herbicide resistant weeds with 262 species are on light globally. Herbicide-resistant weeds have been reported in 70 countries across 92 crops, with 619 scientists from around the world contributing new cases of exposure.Wheat is the crop with the highest evidence of herbicide resistant weeds, followed by maize and rice. The sharp increase in resistant weeds from the 1980s to 2020 directs the trend as a “growing peril” on agriculture that must be addressed timely and prudently.

Production of Antioxidant Molecules in Polygonum aviculare (L.) and Senecio vulgaris (L.) under Metal Stress: A Possible Tool in the Evaluation of Plant Metal Tolerance.

Plants growing on heavy metal (HM)-polluted soils show toxicity symptoms, such as chlorosis and growth reduction, and undergo oxidative stress due to the formation of reactive oxygen species (ROS). Plants overcome oxidative stress by producing a wide range of antioxidant molecules, such as polyphenols and flavonoids. The aim of the present work was to study the accumulation of these molecules in response to increasing concentrations of Cd, Cr, Cu, Ni, Pb and Zn and to assess whether they can be used as a tool in assessing metal-related stress in Polygonum aviculare and Senecio vulgaris. On average, P. aviculare shoots accumulated lower amounts of metals than S. vulgaris shoots. The uptake of all six elements was correlated and proportional to their concentration in the nutrient solution (ρ > 0.9), with the bioaccumulation factor (BAF) being >1 for most of them. The present research demonstrated that 82% of the samples showed a good correlation (|ρ| > 0.5) between the level of polyphenols, flavonoids and antioxidant activity and the metal concentration in plant shoots, confirming that the metal stress level and production of phenolic compounds having antioxidant activity were strictly connected. Nonetheless, the mere quantification of these molecules cannot identify the type of metal that caused the oxidative stress, neither determine the concentration of the stressors. The five tested populations of each species did not show any specific adaptation to the environment of origin.