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Weeds are considered the main reason for crop yield loss in the world. Weed control and management include various treatments such as cultural, physical, chemical, and biological methods. Chemical control of weeds is the most common method; however, the application of commercial synthetic herbicides caused several dangerous hazards in the environment including the appearance of resistant weed biotypes. Prosopis farcta (Banks & Sol.) J.F.Macbr. (Family: Fabaceae), is a common weed plant in the Middle East, where it is hard to eliminate due to its deep and overlapped roots. On the other side, it has many traditional uses around the world. Herein, the essential oil (EO) of P. farcta above-ground parts was extracted via hydrodistillation techniques and then analyzed using gas chromatography-mass spectroscopy (GC-MS). From the GC-MS analysis, 47 compounds were identified with a relative concentration of 98.02%, including terpenes as the main components (95.08%). From overall identified compounds, cubenol (19.07%), trans-chrysanthenyl acetate (17.69%), torreyol (8.28%), davana ether (3.50%), camphor (3.35%), and farnesyl acetone (3.13%) represented the abundant constituents. Furthermore, the phytotoxic activity of the P. farcta EO was assessed against the weed Dactyloctenium aegyptium (L.) Willd. The EO of P. farcta, at a concentration of 100 µL L−1, significantly inhibited the germination, seedling shoot growth, and seedling root growth by 64.1, 64.0, and 73.4%, respectively. The results exhibited that the seedling root growth is the most affected followed by the seed germination and seedling shoot growth with respective IC50 at 64.5, 80.5, and 92.9 µL L−1. It can be concluded that weeds are not absolutely harmful, but they may have beneficial uses, such as, for example as a source of phytochemicals with application in weed control practices (bioherbicides). It is advised to conduct additional research to characterize the allelopathic action of the major chemicals in their pure form, either alone or in combination, against a variety of weeds.

The subject of this bachelor thesis is mapping of the occurrence of the Scotch broom in a defined area along the D6 highway in the section between Karlovy Vary and Sokolov. Assessment of occurrence conditions and comparison with conditions in other localities. The first part includes general information about the plant species and its occurrence. The next part defines the areas of the field reserch. In the third - practical - part, the research of Scotch broom in the defined areas is described in detail. The conclusion summarizes all the above-mentioned chapters.

Chromolaena odorata (L.) R.M. King and H. Robinson (Asteraceae) is one of the worst invasive weeds in Africa, Asia, and the Pacific. Cecidochares connexa (Macquart) (Diptera: Tephritiidae) is a bio...

The invasive annual grasses barb goatgrass (Aegilops triuncialis L.) and medusahead (Elymus caput-medusae L.) are widespread in western states and present management challenges on grasslands. To develop an integrated management strategy for these species, we treated sites in five pastures in Mendocino County, comparing combinations of intensive sheep grazing, glyphosate herbicide (low and high), and application timings (tillering, boot and heading stage). We found that grazing alone reduced barb goatgrass spikelet densities by 68% and the number of seeds per spikelet by 35%. Both rates of glyphosate application without grazing had similar effects on seed production. High and low glyphosate application at tillering resulted in almost complete control of both target species. Boot- and heading-stage applications reduced barb goatgrass density by 39% and 32%, respectively. Application at the boot stage also resulted in an 82% reduction in number of seeds per barb goatgrass spikelet. Our results suggest that intensive grazing may be a useful management strategy to reduce barb goatgrass and medusahead spikelet densities and barb goatgrass seed numbers, especially when integrated with a boot- or heading-stage glyphosate application.

Germination abilities endorsed the successful invasion and establishment regularly of Silverleaf nightshade (Solanum elaeagnifolium Cav.) to be one of the most serious invasive weeds in the world. Therefore, their seed sets were exposed to different thermogradient temperatures and light/dark regimes with and without chemical and physical treatments to determine the germination requirements and conditions. The percentage of seed germination is generally low and reached the optimum at alternating temperature regimes of 20/30 °C (32.8%), followed by 15/25 ℃ (31.5%) and 20/25 ℃ (30.0%), respectively under 12/12 (day/night) within four weeks. While it failed to germinate at constant temperatures. The superlative treatment was achieved from combined heat at 100oC with gibberellic acid at 1000 ppm reached 65% of seed germination over the control. Time exposure and concentration of various chemical and physical promotors have significant effects on germination and breaking their seed dormancy. S. elaeagnifolium seed germination was diminished progressively to ≤ 3000 ppm of NaCl but their growth has more enough resistance. While the range of 8 to 9 pH is preferential to the maximum germination. We concluded that alternating temperatures are basic requirements of S. elaeagnifolium seed germination while it seems a moderate tolerance to salinity and drought stresses. This knowledge will encourage effective methods for management tactics of S. elaeagnifolium.

Ambrosia artemisiifolia L. and Ambrosia trifida L. belong to allochthonous invasive weeds species. They cause great damage in colonized areas because they reduce the yield of agricultural crops, and also with their competitive abilities affect the suppression of other plants and thus affect the change of plant community. As Polygonum aviculare L. is one of the most common weeds on the European continent and a very common companion of rural and urban habitats, this study examined the impact of different ratios of A. artemisiifolia and A. trifida on the occurrence and abundance of P. aviculare. Presence P. aviculare was incereased in treatments with increasing A. trifida and decreased A. artemisiifolia/m2 .

Ambrosia trifida L. belongs to the group of invasive weeds, which in colonized areas cause great damage to the biodiversity of autochthonous flora and vegetation as well as in plant production. It originates from North America wherefrom it has spread to many parts of Europe. In Serbia it is currently locally present in the area of Backa (the northern region of the country). Early and rapid growth rate, vegetative and generative production, high degree of morphological and reproductive plasticity have given it a competitive advantage over many other weeds, hence in many countries it is considered one of the most problematic weeds in agricultural production. A. trifida could cause great damage in root crops, vegetable gardens and orchards and its harmfulness is measured by the negative impact on biodiversity by suppressing indigenous and other non-indigenous species. With its allergens, A. trifida negatively affects human health. Observing its vegetative and generative potential and climate change on the other hand, recent research indicates the potential for the spread of A. trifida in our country and in Europe, which could be a serious risk for agrophytocenoses and the ecosystem as a whole. In 2019, it was added to the EPPO A2 List of quarantine pests recommended. It can be controlled with the use of mechanical, biological and chemical measures.

Monoecious and dioecious forms of the submerged aquatic plant hydrilla, Hydrilla verticillata (Hydrocharitaceae) are invasive weeds in the United States. Monoecious hydrilla is expanding northward ...

A total of 16 different allergenic and invasive weed species belonging to 12 different families collected from different areas of study area. Among the studied plants, most of the species belong to the Asteraceae family. For morphological studies of pollen through LM and SEM the samples were acetalized. We done the fieldwork for the collection of weed plants and also performed the experimental work i.e. SEM and LM for the pollen morphology. Most of the species recorded with pollen of tricolporate and echinate. Species belonging to Asteraceae were considered as most abundant and allergenic as compared to others. The maximum polar diameter was noted in the Convolvulus arvensis is 40.00 µm and the minimum were noted in Oxalis corniculata is 6.15 µm. Maximum exine thickness was noted in convolvulus arvensis is 3.70 µm and Minimum were noted in Sorghum halepense is 1.65 µm. It was noticed that most of the allergenic and invasive weeds found in plain areas of Lakki Marwat during September and April. Present study provides information about the allergenic and invasive weeds plants and their threats to biodiversity. The pollen of such weed plants causes asthma and atopy disease in humans.

In the present study intercropping of two plant species was carried out over a soil contaminated with five heavy metals lead (Pb), cadmium (Cd), chromium (Cr), cobalt (Co) and nickel (Ni). The experimental setup was designed in such a manner that the effluent stream passed intermittently for 60 days through the plant species Acalypha indica and Amaranthus viridis grown on-site after which the species were uprooted and processed further to check the heavy metal concentration in several parts of the plant such as roots, stem, leaves and flowers as well as the soil. The flowers of A. indica accumulated a maximum amount of Pb and least in the stem with a Translocation Factor (TF) of 21.49 and a Bioconcentration Factor (BCF) value of 2 and the highest concentration of Cr in flowers followed by leaves, root and stem regions with a TF of 11.5 and BCF value of 244.59. Co accumulation in A. indica was noted to be maximum in the flowers and least in the stem with a TF of 12.03 and a BCF value of 3.77, while it was highest in the flowers and least in the root with 8.2 and 0.9 TF and BCF values respectively, for Cd, whereas for Ni it was highest in the flowers and least in stem with 18.19 TF and 11.04 BCF. A. viridis accumulated maximum amount of Pb in leaves followed by flowers and least in stem with a TF of 8.64 and BCF of 259.93. It accumulated highest amount of Cr in the leaves followed by flowers, stem and root region with a TF of 10.55 and BCF of 212.49. The leaves of A. viridis accumulated a maximum amount of Co and the least in the stem region with a TF of 7.05 and BCF of 4.95 while the concentration of Cd was highest in leaves and least in roots with 18.37 and 1.61 TF and BCF respectively. A. viridis accumulating trend for Ni was leaves > flowers > root > stem with a TF of 8.15 and BCF of 10.48. Hence as per the values obtained both the species exhibited successful phytoextraction of all the five heavy metals in their aerial parts making both of them good bioaccumulator species.

La présente étude a pour objectif de faire l’état des connaissances traditionnelles endogènes relatives aux plantes locales utilisées contre les bio-agresseurs des cultures et des produits agricoles. A travers une série d’enquêtes ethnobotaniques réalisée de 2018 à 2019 dans la région des Cascades au Burkina Faso, 150 personnes appartenant à l’ethnie Turka ont été interviewées. Les informations recherchées en utilisant des entretiens semi-directifs, ont concerné les noms locaux des plantes, les parties utilisées, les domaines d’utilisation et leurs modes d'utilisation. Les données collectées ont permis de recenser 33 espèces de plantes réparties en 30 genres et 19 familles utilisées traditionnellement contre les bio-agresseurs agricoles. Ces plantes interviennent sélectivement dans trois domaines : la répulsion des insectes, l’inhibition des herbes envahissantes et la construction des greniers. Les espèces sont utilisées soit directement ou transformées en poudre ou en cendre. Les feuilles sont plus utilisées que les autres organes. Cassia nigricans est l’espèce la plus utilisée pour son effet répulsif et Parkia biglobosa pour son effet inhibiteur. Des études approfondies sur les propriétés chimiques des potentielles espèces permettront de réduire l’impact des produits chimiques en agriculture contre les bio-agresseurs.Mots clés : Ethnobotanique, diversité végétale, ennemi agricole, secteur sud-soudanien, Afrique de l’ouest English Title:Traditional knowledge of local plants used against pests of crops and agricultural products among the Turka poeple in Burkina Faso The objective of this study is to provide an overview of endogenous traditional knowledge relating to local plants used against pests of crops and agricultural products. Through an ethnobotanical’s surveys carried out from 2018 to 2019 in the Cascades area in Burkina, 150 Turka ethnic group people were interviewed. Through semi-structured interviews, information looking for were concerned plants local names, their parts used, the domains and the modes of use. Data collected allowed to identify 33 plants’ species belonged to 30 genera and 19 families, used traditionally against agricultural pests. These plants are selectively involved in three domains: repelling insects, inhibiting invasive weeds and building lofts. Species are used either directly or processed into powder or ash. The leaves are used more than other organs. Cassia nigricans is the most used species for its repellent effect and Parkia biglobosa for its inhibitory effect. In-depth studies on the chemical properties of potential species will reduce the impact of chemicals in agricultural against pests.Keywords: Ethnobotany, plant diversity, agricultural pest, South Sudanese sector, West Africa

Polyploidy is a pervasive and recurring phenomenon across the tree of life, which occurred at variable time scales, ecological amplitudes and cell types, and is especially prominent in the evolutionary histories of plants. Importantly, many of the world's most important crops and noxious invasive weeds are recent polyploids. Polyploidy includes two major types, autopolyploidy, referring to doubling of a single species genome, and allopolyploidy referring to doubling of two or more merged genomes via biological hybridization of distinct but related species. The prevalence of both types of polyploidy implies that both genome doubling alone and doubling coupled with hybridization confer selective advantages over their diploid progenitors under specific circumstances. In cases of allopolyploidy, the two events, genome doubling and hybridization, have both advantages and disadvantages. Accumulated studies have established that, in allopolyploidy, some advantage(s) of doubling may compensate for the disadvantage(s) of hybridity and vice versa, although further study is required to validate generality of this trend. Some studies have also revealed a variety of non-Mendelian genetic and genomic consequences induced by doubling and hybridization separately or concertedly in nascent allopolyploidy; however, the significance of which to the immediate establishment and longer-term evolutionary success of allopolyploid species remain to be empirically demonstrated and ecologically investigated. This review aims to summarize recent advances in our understanding of the roles of hybridization and genome doubling, in separation and combination, in the evolution of allopolyploid genomes, as well as fruitful future research directions that are emerging from these studies.

Climate change is predicted to increase the frequency and impact of plant invasions, creating a need for new control strategies as part of mitigation planning. The complex interactions between invasive plants and biocontrol agents have created distinct policy and management challenges, including the effectiveness and risk assessment of biocontrol under different climate change scenarios. In this brief review, we synthesize recent studies describing the potential ecological and evolutionary outcomes for biocontrol agents/candidates for plant invaders under climate change. We also discuss potential methodologies that can be used as a framework for predicting ecological and evolutionary responses of plant-natural enemy interactions under climate change, and for refining our understanding of the efficacy and risk of using biocontrol on invasive plants.

Field research of LRP was supported by AAS 4158 project of the Australian Antarctic Science Program.LRP was also recipient of a SCAR fellowship. MMS was supported by a FPI PhD Grant (BES-2013-062910) that was funded by the Spanish Ministry of Economy and Competitiveness.

In this research, two algorithms first, considered to be one of hybrid algorithms. And it is algorithm represents invasive weed optimization. This algorithm is a random numerical algorithm and the second algorithm representing the grey wolves optimization. This algorithm is one of the algorithms of swarm intelligence in intelligent optimization. The algorithm of invasive weed optimization is inspired by nature as the weeds have colonial behavior and were introduced by Mehrabian and Lucas in 2006. Invasive weeds are a serious threat to cultivated plants because of their adaptability and are a threat to the overall planting process. The behavior of these weeds has been studied and applied in the invasive weed algorithm. The algorithm of grey wolves, which is considered as a swarm intelligence algorithm, has been used to reach the goal and reach the best solution. The algorithm was designed by SeyedaliMirijalili in 2014 and taking advantage of the intelligence of the squadrons is to avoid falling into local solutions so the new hybridization process between the previous algorithms GWO and IWO and we will symbolize the new algorithm IWOGWO.Comparing the suggested hybrid algorithm with the orig.

In this paper, two algorithms first, considered to be one of hybrid algorithms. And it is algorithm represents an Invasive Weed Optimization (IWO). This algorithm is a random numerical algorithm and the second algorithm repre- senting the Bat Optimization Algorithm (BA). This algorithm is one of the swarm intelligence algorithms in smart optimization. The Invasive Weed Optimization Algorithm is inspired by nature, as the weeds have colonial behavior and were introduced in 2006 by Mehrabian and Lucas. Invasive weeds pose a serious threat to crops due to their adaptability and pose a threat to the overall planting cycle. In the Invasive Weed Optimization Algorithm, the behavior of these weeds was analyzed and implemented. The Bat algorithm, which is called a swarm intelligence algorithm, was used to achieve the goal and the best solution. The algorithm was designed by Yang in 2010 and taking advantage of the intelligence of the squadrons is to avoid falling into local solutions so the new hybridization process between the previous algorithms Invasive Weed Optimization (IWO) and Bat Optimization Algorithm (BA) and we will symbolize the new algorithm IWO-BA Comparing the hybrid algorithm suggested with the original algorithms the results were excellent. In most research functions, the optimal solution has been found.

Agriculture is the mainstay of the Ethiopian and a key sector of its economy. However, Lack of productive and environmentally friendly technology is not widely applicable elsewhere. Likewise, the vermicomposting technology is a recently emerging science which not effectively transferred to the users across the country. Thus, this review is aimed to shine the importance, unexploited opportunities and the challenges hindered for further expansions in Ethiopian context. Vermicompost is among the powerful organic fertilizers which enhance soil Fertility and productivity. As agrarian society; there are plenty of raw byproducts and weed species which are not center of focus (i.e cattle waste, crop residues and invasive weeds like P.Juliflora, P.hysterophorus and E.crassipes respectively). However, there are many constraints there like policy issue, handling problems and sensitivity of the worms for different environmental factors which hindered to invest on a wide range. Generally, the number and weight of vermiculture as well as amount of produced casts are promised and every possible ways were recommended to entertain on the large scale.

The article explores the unique perception towards students’ future aspects regarding enrollment in higher education by featuring AI (artificial intelligence) techniques and applications in solving real-world remote problems. Some students might feel that higher education only implies the study of domains like quantum mechanics, fluid mechanics, advanced mathematics or chemistry, but that is not the case. Artificial Intelligence and its applications to solve real-world problems also forms a major portion of higher education. Some of these topics may include fuzzy techniques, evolutionary algorithms, neural or swarm intelligence etc. But apart from this, the chapter highlights some of the amusing arguments of AI in higher education for implementing human fuzziness, bio-inspired evolutionary algorithms like genetic, neural, swarm intelligence, ecological colonization of invasive weeds for solving real-world optimization problems to an exact and accurate limit. AI is almost used in every discipline of higher education in direct or indirect form. Thus, a different way of analyzing the future aspects in education is required by students for their active participation in higher education. Keywords: Artificial intelligence, higher education, bio-inspired evolutionary algorithms, students.

The life history and host range of the South American defoliator Paectes n. sp. (Lepidoptera: Euteliidae) was evaluated to determine its suitability for classical biological control of inva...

Despite their putative invasive potential, Miscanthus taxa have been increasingly viewed as promising crops for bioenergy production. Miscanthus x giganteus is cultivated worldwide due to its high productivity, and its non-spreading growth limits its risk of invasion. However, the genetic uniformity of its unique cultivated clone has recently been questioned. We used morphometry, nuclear microsatellites, AFLP fingerprints and nrDNA ITS barcoding to assess Miscanthus genotypes cultivated in eastern France. As expected, the globally cultivated clone was the main morphotype and genotype of our samplings; however, we also identified a second genotype, assigned to M. sacchariflorus, in the sampled fields. Morphological differentiation partially overlaps genotypic assignation, probably due to disturbance at the crop edges. We also show that Miscanthus taxa are misidentified in commercial nurseries. Our study confirms previous reports of the occurrence of other accessions in fields of M. x giganteus. These taxonomic confusions limit the certainty that a single clone of M. x giganteus is cultivated. In this context, M. x giganteus crop fields may actually promote the dispersal of invasive Miscanthus taxa.

The life history and host range of the South American leaf-tier Tentamen atrivirgulatum Metz, 2019 (Lepidoptera: Gelechiidae) was evaluated to determine its suitability for classical biolog...

Abutilon theophrasti Medik, Ambrosia artemisiifolia L., Datura stramonium L. and Xanthium strumarium L. are four well-known invasive weed species that are widespread in many crops. Laboratory experiments were conducted to evaluate the allelopathic effects of decomposition products of these four invasive weeds on seed germination and early seedling growth of tomato. The results of the study showed that decomposition products obtained from A. theophrasti, A. artemisiifolia, D. stramonium and X. strumarium had different allelopathic impacts on germination and seedling growth of tomato. The degree of inhibition or stimulation depended on weed species and type of decomposition product. Root decomposition products of all species except X. strumarium decreased the early growth of tomato (2-37%). X. strumarium had only stimulating effect on early growth of tomato (1-86%). Also, the results showed that leaves of the other three invasive weed species had stimulating effects on early growth of tomato (1-53%). Hence, the allelopathic potential of X. strumarium, as well as the leaf decomposition products of the other three invasive weed species could be used to develop an appropriate technology to improve tomato production.

Invasive plants cause a global loss of biodiversity, pose a major threat to the environment and economy, and also significantly affect agricultural production and food security. Plant growth regulators (PGRs) are widely used in agricultural production and might also affect invasive weeds distributed around crops in various ways. At present, there are few studies concerning whether there are significant effects of PGRs on invasive weeds. In this study, two widely used PGRs in paddy fields, gibberellic acid (GA) and paclobutrazol (PAC), were applied on Oryza sativa and a noxious weed Alternanthera philoxeroides, which is frequently distributed in paddy fields. The purpose of this study was to investigate if there are different responses of rice and weeds to these two plant regulators and the significant effects of PGRs on invasive weeds. The results showed that GA significantly promotes the total biomass of A. philoxeroides by 52.00%, but does not significantly affect that of O. sativa. GA significantly increases the growth of aboveground and belowground A. philoxeroides, but not that of O. sativa. On the other hand, PAC extremely inhibited the aboveground and belowground biomass of A. philoxeroides by more than 90%, but did not significantly inhibit the belowground biomass of O. sativa. PAC also enhanced the leaf nitrogen content and chlorophyll content of A. philoxeroides, but not the traits of O. sativa. Therefore, the effects of PGRs are significantly different between rice and the invasive weed. The potential promotion effects of PGRs on weeds that are frequently distributed in farmland warrant sufficient attention. This is probably one of the important reasons why invasive weeds can successfully invade the agricultural ecosystem with large human disturbance. This study might sound an alarm for weed control in paddy fields.

In the present work, a dynamic stochastic method is proposed and used for the synthesis of uniform linear antenna arrays. The proposed method combines the classical invasive weeds (IWO) and the mutation process, which makes it robust, simple and shows flexibility to be adapted. The dynamic IWO applies the mutation process in the calculation of standard deviation during the spatial dispersal process of produced seeds while keeping the mean at the parent plants. In the mutation process, if special conditions were achieved, the standard deviation would be re-initialized. This proposed method tries to achieve an optimal array pattern by acting on the relative amplitude excitation of each element in the linear array for an optimal inter-element spacing. The optimal array pattern has deep or broad nulls in some directions of interferences with low sidelobes level. The objective of the synthesis is to get amplitude excitations with low dynamic range ratio (DRR), which facilitates the design of beamforming feed network. To illustrate the robustness of the proposed method, numerical examples are presented and compared with the obtained results using bees algorithm (BA), bacterial foraging algorithm (BFA), real genetic algorithm (RGA), and the corresponding reference array pattern for each example.

The invasive weed Asystasia gangetica was investigated for its potential as a biomonitor and as a phytoremediator of potentially toxic metals (PTMs) (Cd, Cu, Ni, Pb, and Zn) in Peninsular Malaysia owing to its ecological resistance towards unfavourable environments. The biomonitoring potential of PTMs was determined based on the correlation analysis of the metals in the different parts of the plant (leaves, stems, and roots) and its habitat topsoils. In the roots, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 2.18, 9.22 to 139, 0.63 to 5.47, 2.43 to 10.5, and 50.7 to 300, respectively. In the leaves, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 1.16, 7.94 to 20.2, 0.03 to 6.13, 2.10 to 21.8, and 18.8 to 160, respectively. In the stems, the concentrations (mg/kg dry weight) of Cd, Cu, Ni, Pb, and Zn ranged from 0.03 to 1.25, 5.57 to 11.8, 0.23 to 3.69, 0.01 to 7.79, and 26.4 to 246, respectively. On the other hand, the phytoremediation potential of the five metals was estimated based on the bioconcentration factor (BCF) and the translocation factor (TF) values. Correlation analysis revealed that the roots and stems could be used as biomonitors of Cu, the stems as biomonitors of Ni, the roots and leaves as biomonitors of Pb, and all three parts of the plant as biomonitors of Zn. According to the BCF values, in the topsoil, the “easily, freely, leachable, or exchangeable” geochemical fractions of the five metals could be more easily transferred to the roots, leaves, and stems when compared with total concentrations. Based on the TF values of Cd, Ni, and Pb, the metal transfer to the stems (or leaves) from the roots was efficient (&gt, 1.0) at most sampling sites. The results of BCF and TF showed that A. gangetica was a good phytoextractor for Cd and Ni, and a good phytostabilizer for Cu, Pb, and Zn. Therefore, A. gangetica is a good candidate as a biomonitor and a phytoremediator of Ni, Pb, and Zn for sustainable contaminant remediation subject to suitable field management strategies.

Parthenium hysterophorus L. is one of the most invasive weeds and belongs to the family Asteracaeae.

Soil salinity represents one of the most restrictive environmental factors for agriculture worldwide. In the present study, the salt tolerance of two weeds of the genus Amaranthus, A. albus and A. hybridus, the latter cultivated as green vegetable in Africa, were analysed. Both species showed a remarkable salt tolerance phenotype during germination and vegetative growth. To evaluate the percentage and rate of germination, seeds were germinated in Petri dishes in a germination chamber under increasing concentrations up to 300 mM NaCl. Higher concentrations of salt ranging from 150 to 600 mM NaCl were applied for one month to plants grown in individual pots in the greenhouse. All seeds of A. albus germinated in the control and almost half of the seeds under 200 mM NaCl, but only 4% of the seeds under 250 mM NaCl. In A. hybridus, germination was considerably lower in all treatments and was completely prevented at 250 mM NaCl. The plant growth of both species was severely affected by high salt concentrations of 450 and 600 mM NaCl, but not under lower concentrations. At this stage of the biological cycle, A. hybridus showed a higher salt tolerance, as indicated by the smaller reduction in its growth parameters. The dry weight of leaves and roots of plants receiving 600 mM NaCl decreased in comparison to control: less than 60% in A. hybridus but more than 70% in A. albus. The salt tolerance of the two species contributes to their invasive potential, but on the other hand represents a useful trait when considering them as potential crops for the future.

The threat posed by poisonous weeds to grassland ecosystems may be exacerbated by climate change mainly driven by carbon dioxide (CO2) emissions. Achnatherum inebrians is a common and poisonous grassland weed that is seriously endangering the sustainable development of prairie animal husbandry in Western China. Understanding the influence of future climate change under different CO2 emission scenarios on the potential distributions of A. inebrians is critical for planning agricultural strategies to manage the continued invasion. An ecological niche model (ENM) was developed using Maxent to predict the potential distribution of A. inebrians under three different CO2 emission scenarios. Occurrence records of A. inebrians were selected utilizing the nearest neighbor method. Six environmental variables, which were identified through principal component analysis, correlation analysis and their contribution rates, were used to perform the ENM. At the same time, considering the uncertainties of predicting future climates, four global circulation models were used for the Maxent projections with average results calculated. Our results demonstrate differential influences of various CO2 emission scenarios on the potential distributions of A. inebrians. Before 2050, high CO2 emission scenarios resulted in a wider potential distribution of A. inebrians, when compared to low CO2 emission scenarios. However, after 2050, the low CO2 emission scenarios were more conducive to an expanded potential distribution. In addition, after 2050, high CO2 emission scenarios maintain the geographical distribution centroids of A. inebrians in lower latitudes, while low CO2 emission scenarios result in distribution centroids rising to higher latitudes. Further, low CO2 emission scenarios resulted in the average potential distribution elevation dropping lower than in high CO2 emission scenarios.

Diverse freshwater biological communities are threatened by invasive aquatic alien plant (IAAP) invasions and consequently, cost countries millions to manage. The effective management of these IAAP invasions necessitates their frequent and reliable monitoring across a broad extent and over a long-term. Here, we introduce and apply a monitoring approach that meet these criteria and is based on a three-stage hierarchical classification to firstly detect water, then aquatic vegetation and finally water hyacinth (Pontederia crassipes, previously Eichhornia crassipes), the most damaging IAAP species within many regions of the world. Our approach circumvents many challenges that restricted previous satellite-based water hyacinth monitoring attempts to smaller study areas. The method is executable on Google Earth Engine (GEE) extemporaneously and utilizes free, medium resolution (10–30 m) multispectral Earth Observation (EO) data from either Landsat-8 or Sentinel-2. The automated workflow employs a novel simple thresholding approach to obtain reliable boundaries for open-water, which are then used to limit the area for aquatic vegetation detection. Subsequently, a random forest modelling approach is used to discriminate water hyacinth from other detected aquatic vegetation using the eight most important variables. This study represents the first national scale EO-derived water hyacinth distribution map. Based on our model, it is estimated that this pervasive IAAP covered 417.74 km2 across South Africa in 2013. Additionally, we show encouraging results for utilizing the automatically derived aquatic vegetation masks to fit and evaluate a convolutional neural network-based semantic segmentation model, removing the need for detection of surface water extents that may not always be available at the required spatio-temporal resolution or accuracy. The water hyacinth species discrimination has a 0.80, or greater, overall accuracy (0.93), F1-score (0.87) and Matthews correlation coefficient (0.80) based on 98 widely distributed field sites across South Africa. The results suggest that the introduced workflow is suitable for monitoring changes in the extent of open water, aquatic vegetation, and water hyacinth for individual waterbodies or across national extents. The GEE code can be accessed here.

With increasing globalization, trade, and human movement, the rate of alien species introduction has increased all around the globe. In addition, climate change is thought to exacerbate the situation by allowing range expansion of invasive species into new areas. Predicting the distribution of invasive species under conditions of climate change is important for identifying susceptible areas of invasion and developing strategies for limiting their expansion. We used Maxent modeling to predict the distribution of one of the world's most aggressive invasive weeds, Ageratina adenophora (Sprengel) R. King and H. Robinson, in the Chitwan–Annapurna Landscape (CHAL) of Nepal under current conditions and 3 future climate change trajectories based on 3 representative concentration pathways (RCPs 2.6, 4.5, and 8.5) in 2 different time periods (2050 and 2070) using species occurrence data, and bioclimatic and topographic variables. Minimum temperature in the coldest month was the most important variable affecting the distribution of A. adenophora. About 38% (12,215 km2) of the CHAL area is climatically suitable for A. adenophora, with the Middle Mountain physiographic region being the most suitable one. A predicted increase in current suitable areas ranges from 1 to 2% under future climate scenarios (RCP 2.6 and RCP 8.5). All protected areas and 3 physiographic regions (Siwaliks, High Mountain, High Himalaya) are likely to gain climatically suitable areas in future climate scenarios. The upper elevational distribution limit of the weed is expected to expand by 31–48 m in future climate scenarios, suggesting that the weed will colonize additional areas at higher elevations in the future. In conclusion, our results showed that a vast area of CHAL is climatically suitable for A. adenophora. Expected further range expansion and upslope migration in the future make it essential to initiate effective management measures to prevent further negative impacts of this invasive plant.

Three main Ambrosia species (Ragweed)grow in Israel of which A. artemisiifolia and A. tenuifolia are of restricted distribution and the invasive A. confertiflora is the most abundant and widely distributed in roadsides, open land, waterways and cultivated fields and orchards. The present research was aimed to study the effect of temperatures regimes on the development and growth of the three main Ambrosia species in Israel, to elucidate the environmental conditions and plant traits that affect their development and infestation patterns. Seed germination studies were conducted in petri dish and pots. Ambrosia spp. plant emergence and development kinetics of different organs were conducted in pots and trays in a net house and at different temperature regimes in a phytotron. A. confertiflora, A. artemisiifolia and A. tenuifolia germinate best in light from the soil surface with no prerequisite of a stratification period. A. confertiflora seed emergence is inhibited at high temperature regimes (28-34oC), A. artemisiifolia at low temperature regimes (10-16oC) C, while A. tenuifolia is less affected by the temperature regimes. A. confertiflora plant height increased with increasing temperatures, and at lower temperatures develops a rosette. Root and rhizome biomass was less affected by the different temperatures regimes, A. artemisiifolia overground mass was not affected by temperature regimes while A. tenuifolia overground mass was reduced only at lower temperatures. The factors affecting A. confertiflora fast invasion and establishment are: easy long-distance seed dissemination, prolific seed germination and sprouting of rhizomes, rapid growth, massive viable seed fecundity, and adaptation to changing and adverse environmental conditions.

Thermogravimetric analysis of two invasive weeds Prosopis juliflora (PJ) and Lantana camara (LC) are carried out by pyrolysis under dynamic conditions (20 to 900 °C) at different heating rates 5, 10, 20 and 40 °C/min. Gross calorific values of PJ and LC are estimated to 18.2 and 18.92 MJ/kg respectively. Activation energy obtained by FRM, M-FRM, KAS, OFW, STR, NL-INT, NL-DIF methods are 157.56, 151.24, 140.86, 143.39, 140.74, 141.19, 157.59 kJ/mol for PJ and 169.98, 167.67, 149.39, 151.51, 149.23, 149.70, 169.98 kJ/mol for LC respectively. Kinetic compensation effects were well fitted with the experimental data, which provided the value of the pre-exponential factor. To identify the appropriate reaction mechanism, the Popescu and Master-plot methods are employed. Thermodynamic parameters (ΔG, ΔH, and ΔS) are also determined by NL-INT, NL-DIF, and M-FRM methods. Results of kinetic and thermodynamic parameters confirm the suitability of PJ and LC invasive weeds as potential biomasses for pyrolysis process.

espanolEn este documento se revisa la experiencia en los trabajos de control y erradicacion de plantas invasoras realizados en los cultivos de Cataluna a partir del ano 2005, desde el punto de vista de su gestion. Los resultados permiten afirmar que se trata de un proceso complejo y no inmediato. Dado que evitar la entrada de nuevas plantas resulta muy dificil y costoso, resulta fundamental para tener exito, una rapida deteccion y una pronta actuacion sobre la mala hierba. Esto pone en relieve la importancia de disponer de una buena red de tecnicos sobre el terreno que de aviso cuando se detecte un problema, y tambien disponer de normativa que permita actuar de forma inmediata. La evaluacion del riesgo de invasion y de la viabilidad del control de cada mala hierba de forma individual, aumenta la probabilidad de tener exito en el proceso de erradicacion y ayuda a optimizar los recursos. Se describen los caracteres biologicos que se han observado como mas importantes para el exito de una nueva introduccion. Se repasan los criterios a tener en cuenta para el inicio y la finalizacion de actividades en una campana de gestion ante la introduccion de una nueva especie en los campos de cultivo de un territorio. Asi mismo, se mencionan los criterios economicos ligados a estas actividades, los costes de su realizacion y la posibilidad de indemnizar a los agricultores afectados analizando los baremos a tener en cuenta EnglishThis document describes the experience in the control and eradication tasks of invasive weeds carried out in the crops of Catalonia since 2005, from its management point of view. The results allow to affirm that is a complex and not immediate process. Since avoiding the arrival of new plants is very difficult and expensive rapid detection and rapid action on introduced weeds are essential for success. This fact highlights the importance of having a good network of technicians all around the agricultural areas that transfer the information when a problem is detected; also having regulations that allow immediate action is essential. The invasion risk evaluation and the viability of weed control increases the likelihood of success in the eradication process and helps optimizing resources. The biological characters that have been observed as most important for the success of a new introduction are described. The criteria to be taken into account for the start and end of activities in a management campaign after the introduc - tion of a new species in the fields of a territory are reviewed. Likewise, the economic criteria related to these activities are mentioned, such as the costs of their realization and the possibility of compensating economically the affected farmers by analyzing the criteria to be taken into account

In the present study, we conducted field surveys to detect the population density of the most important invasive weed species and their associated virus vectoring aphids in crops grown under high input field (HIF) vs. low-input field (LIF) conditions, with and without fertilizers and pesticides. The most frequent invasive weed species were annual fleabane, Erigeron annua (L.), Canadian horseweed, Erigeron canadensis (L.) and Canadian goldenrod, Solidago canadensis (L.). These species were predominantly hosts of the aphids Brachycaudus helichrysi and Aulacorthum solani under both management systems. The 13% higher coverage of E. annua under LIF conditions resulted in a 30% higher B. helichrysi abundance and ∼85% higher A. solani abundance compared with HIF conditions. To reveal the incidence of virus infection in crop plants and invasive weeds, high-throughput sequencing of small RNAs was performed. Bioinformatics analysis combined with independent validation methods revealed the presence of six viruses, but with strikingly different patterns under LIF and HIF conditions. Their presence without symptoms in invasive weeds and crop plants supports the necessity of employing new approaches to those currently employed in invasive weed management. These findings also suggest that invasive weeds could serve as hosts for local aphid species and reservoirs for plant pathogenic viruses, both under low and high input management systems. In this light, as here demonstrated, viruses transmitted by local aphid species were found to differ between the management systems; hence, the importance of B. helichrysi and A. solani as virus vectors in particular clearly needs to be re-evaluated. Altogether, we accept that the present study is a pilot one and individual virus vectoring of aphids still needs to be directly tested. Even so, it represents one of the first contributions to this particular area, and thereby paves the way for further similar applied research in the future.

The weeds are generally defined as the unwanted plants growing in an agricultural field. The weeds are not very useful and occupy the space in the field to successfully outnumber the plants that are cultivated for regular use. Thus, a popular agronomical belief is that “The Weeds Always Win”. Weeds typically generate large numbers of seeds, supporting their spread by wind or some other natural factors. They can also grow in adverse conditions and are very adaptable. These unique properties of weed growth shows the way for the development of optimization techniques. One of the algorithms motivated by this common phenomenon in agriculture field is based on the expansion of invasive weeds. The algorithm is known as Invasive Weed Optimization (IWO). In this chapter, we have described the IWO algorithm and its use in obtaining the optimal solution of common popular functions.

A new technology for the detection and chemical treatment of the Sosnowski hogweed using neural networks and ground and air robotic systems was tested. Confirmation is obtained of the possibility of detecting invasive weeds and their state using satellite imagery and UAVs. The features of the chemical treatment of dicotyledonous plants using UAVs are investigated. The effectiveness of the weed control by chemical pesticides sprayed with UAVs was confirmed by the example of the “Graund” herbicide.

About 10% of the weeds introduced to new habitats can compete with and replace native plants. These invasive species cause a decline of diversity, productivity, and stability, they disrupt ecosystem processes, and they even alter the soil microbiome. During the past few centuries, people have introduced invasive weeds to every ecosystem on the planet. A few Eurasian weeds that reached the interior of the Western USA during the 1600s spread along trails and roads across the land. Mid-nineteenth century explorers reported finding invasive weeds in remote mountain canyons visited only by loggers (Watson 1874). Today the same weeds dominate many millions of acres. In 2007, the U.S. Bureau of Land Management (BLM) the largest landholder in the Western USA had this to say about the spreading weeds.

Natural herbicides based on essential oils (EOs) extracted from aromatic plants are gaining relevance in contemporary agriculture. Due to their allelopathic properties, they have an inhibitory effect on the germination and growth of different species, having, in general, the advantage of high specificity. For this reason, the analysis of the effects of these natural compounds on noxious weeds is continuously increasing. In the present study, three commercial EOs extracted from Mentha piperita L., Thymbra capitata (L.) Cav. and Santolina chamaecyparissus L. were tested on two invasive weeds with an increasing presence in southern Europe, Erigeron bonariensis L. and Araujia sericifera Brot. Five concentrations (0.125, 0.25, 0.50, 1 and 2 µL mL–1) were tested in a randomized manner for each essential oil and five replicates with 20 seeds each for E. bonariensis and 10 replicates with 10 seeds each for A. sericifera. Two higher concentrations of 4 and 8 μL mL–1 of the three EOs were applied with irrigation on the plants of the two species at the vegetative growth stage. The number of replicas for each treatment and species was 7. The results obtained confirmed the significant inhibitory effects on seed germination and early seedling development, especially in E. bonariensis; of the three EOs, peppermint had the strongest effect, completely preventing germination in both species. Multivariate analysis, performed on several morphological traits scored after one month of treatment in young plants, showed a different pattern: the highest inhibition was recorded in A. sericifera and the greatest reduction in growth in the treatment with the highest dose of Santolina EO. The results obtained revealed the efficacy of these natural compounds and the specificity of their toxicity according to the species and stage of development.

Invasive aquatic macrophytes in Lake Victoria including water hyacinth (Eichhornia crassipes) exhibit periodic cyclical patterns of decline and proliferation with attendant ecological and economic impacts. This study aimed to monitor the extent of macrophytes and other invasive weeds on Lake Victoria to establish their impact on fisheries. The study employed a combination of remote sensing and geographical information system (GIS) techniques to estimate the coverage of water hyacinth and other invasive macrophytes. Data on fish landings and their respective market values were acquired from the Electronic Fish Market Information Service (EFMIS) database, which is hosted by the Kenya Marine and Fisheries Research Institute (KMFRI). Analysis of consistent temporal satellite data showed that the weeds frequently cover sheltered bays and river mouths. These areas of Winam Gulf had higher coverage (average 5000 ha) of macrophytes than the open waters (

Chinese tallowtree, Triadica sebifera (L.) Small (Euphorbiaceae), is one of the worst invasive weeds of the southeastern USA impacting coastal wetlands, forests, and natural areas. A proposed biolo...

This study attempts to measure the growth of invasive plant species Mikania micrantha Kunth, which is considered as one among the top hundred worst invasive weeds worldwide. Seedlings of Mikania micrantha were propagated through vegetative part as well as seed for the study. The juvenile plants were allowed to grow on different hosts such as poles (nonliving support) and a garden plant (living support) in a soil that contains minimum requirements for growth. Growth of the seedlings was recorded daily by measuring the length of the stem, a number of twines and number of leaves for a growth period of fourteen days. The plants thrived on both types of support. The growth rate was higher in vegetatively propagated plants. It ensures re-growth even from a single node and is responsible for successful invasion of the weed after mechanical weeding.

Ageratina adenophora is one of the major invasive weeds that causes instability of the ecosystem. Research has reported that A. adenophora produces allelochemicals that inhibit the growth and development of food crops, and also contain some toxic compounds that cause toxicity to animals that consume it. Over the past decades, studies on the identification of major toxic compounds of A. adenophora and their toxic molecular mechanisms have been reported. In addition, weed control interventions, such as herbicides application, was employed to reduce the spread of A. adenophora. However, the development of therapeutic and prophylactic measures to treat the various A. adenophora—induced toxicities, such as hepatotoxicity, splenotoxicity and other related disorders, have not been established to date. The main toxic pathogenesis of A. adenophora is oxidative stress and inflammation. However, numerous studies have verified that some extracts and secondary metabolites isolated from A. adenophora possess anti-oxidation and anti-inflammation activities, which implies that these extracts can relieve toxicity and aid in the development of drug or feed supplements to treat poisoning-related disorders caused by A. adenophora. Furthermore, beneficial bacteria isolated from rumen microbes and A. adenophora can degrade major toxic compounds in A. adenophora so as to be developed into microbial feed additives to help ameliorate toxicity mediated by A. adenophora. This review presents an overview of the toxic mechanisms of A. adenophora, provides possible therapeutic strategies that are available to mitigate the toxicity of A. adenophora and introduces relevant information on identifying novel prophylactic and therapeutic measures against A. adenophora—induced toxicity.

Predicting the distribution of invasive weeds under climate change is important for the early identification of areas that are susceptible to invasion and for the adoption of the best preventive measures. Here, we predicted the habitat suitability of 16 invasive weeds in response to climate change and land cover changes in South Korea using a maximum entropy modeling approach. Based on the predictions of the model, climate change is likely to increase habitat suitability. Currently, the area of moderately suitable and highly suitable habitats is estimated to be 8877.46 km2, and 990.29 km2, respectively, and these areas are expected to increase up to 496.52% by 2050 and 1439.65% by 2070 under the representative concentration pathways 4.5 scenario across the country. Although habitat suitability was estimated to be highest in the southern regions (&lt, 36° latitude), the central and northern regions are also predicted to have substantial increases in suitable habitat areas. Our study revealed that climate change would exacerbate the threat of northward weed invasions by shifting the climatic barriers of invasive weeds from the southern region. Thus, it is essential to initiate control and management strategies in the southern region to prevent further invasions into new areas.

Integrating classical biological control with other management techniques such as herbicide, fire, mechanical control, grazing, or plant competition, can be the most effective way to manage invasive weeds in natural areas and rangelands. Biological control agents can be protected from potential negative impacts of these weed control methods through untreated refugia or by applying the treatment at a time when the agent is not vulnerable. A literature review of experiments that integrated biological control with other management strategies from 1987 to 2017 yielded 39 terrestrial and 16 aquatic studies. The tactics most frequently integrated with biological control were herbicide applications and plant competition. Despite numerous examples of successful programs and calls for more widespread integration of biological control with other weed management strategies, there was no increase in the number of studies reported annually over time. Additional studies investigating the ecological and economic benefits of integrated weed management are needed.

Because of the globalization and global warming the emergence of invasive weeds in Hungary are more common. The woolly cupgrass (Eriochloa villosa [Thunb.] Kunth) is published as an important invasive weed in Hungary. Woolly cupgrass is native in East Asia and it spreads into several parts of the World and causes difficulties in plant protection. It has been spreading extensively during the last few years,as the weed shows a very serious invasion potential.