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We studied the allelopathic effects of aqueous extracts of two weed species viz., Ageratum conyzoides L. and Parthenium hysterophorus L. on seed germination and early seedling growth of bell pepper plants infected by Phytophthora capsici. The parameters studied were: Percent disease index (PDI), seed germination, seedling fresh weight and seedling height of bell pepper. The inhibition (%) of different aqueous extracts of both donor weed plants ranged from 74.82 % to 91.16 %. Of all 4-aqueous extracts, ethanolic extract of leaves showed the best antifungal effects. The GC-MS analysis revealed that these extracts had anti-fungal properties due to the presence of distinct groups of active compounds, suggesting their applied role in disease management. These allelochemicals can be potential tool to manage important plant diseases and replace synthetic fungicides for crop disease management. [ABSTRACT FROM AUTHOR]

We studied the allelopathic effects of mulch and aqueous extracts of Rice (Oryza sativa L.) straw and on growth of 8-weeds: Phalaris minor L., Cynodon dactylon L., Chenopodium album L., Rumex denticulate L., Anagalis arvensis L., Melilotus spp L., Parthenium hysterophorus L. and Cyperus rotundus (L.) was analyzed. Rice straw mulch at 4.0 t/ha and rice aqueous solution (10 g/L) spray significantly reduced these weeds density (Number/m2) (54, 55, 66, 79, 85, 73, 54 and 39 during 2020-21) respectively, than control. Rice straw mulch 4 t/ha followed by (metsulfuron methyl 4 g a.i./ha + clodinafop propargyl 60 g a.i./ha) and clodinafop propargyl 75 % of 60 g a.i./ha + rice aqueous solution (10 g/L) spray significantly reduced the density of test weeds. Density of grass weeds decreased in zero-till, but broad leaved weeds decreases in conventional tillage. Wheat growth (dry matter accumulation: g/plant), number of tillers per m, leaf area index (LAI) and yield) significantly increased by rice straw mulch at 4 t/ha followed by rice aqueous solution (10 g/L) spray than control. [ABSTRACT FROM AUTHOR]

This review consists of life cycle of Cuscuta its impact on main plants and its management techniques. There are various methods (physical, mechanical, chemical and biological) to control the infection of Cuscuta. Furthermore, the Integrated used management IWM of Cuscuta is a superior for productivity of both crops and ecosystems. The IWM has various elements (cultural practices, physical removal, biological control and chemical control). In addition, the impact of allelopathy and the use of genetic engineering stops the proliferation of Cuscuta. The IWM combined with allelopathy and biotechnology can effectively limit the infection of Cuscuta. [ABSTRACT FROM AUTHOR]

We investigated the allelopathic inhibitory effects of harmala (Peganum harmala L.) seeds, seed powder and water extracts on barley (Hordeum vulgare L.) seed germination and seedling growth. The harmala seeds inhibited the barley germination and seedling growth and also significant effected the on root growth than on shoot growth. Ground harmala seed (0.06-0.72 g) had highly significant inhibitory effects on barley germination, except at the lowest concentrations (0.06 and 0.12 g/dish). Water extracts of harmala seeds concentrations (0.6-7.2 %) inhibited the barley germination and seedling growth by 2.4 %. There were clear inhibitory effects on root elongation and plumule growth. Additionally, the harmala extract caused radicle decay in barley seedlings. In the field, 1 g of ground harmala seeds inhibited the germination and growth of barley seeds and monthly irrigation with 5 g/L inhibited the fresh and dry weight of barley plants. The inhibitory effects were also on spikes and roots, number and weight of seeds. The germination and growth of new seeds were also inhibited. Similarly, adding 5 g of ground harmala seeds significantly affected the fresh and dry weight of barley plants, with leaves, stems and roots were more affected than spikes. Overall, this study provides an explanation for the absence of barley growth in harmala-infested soil. [ABSTRACT FROM AUTHOR]

We did a preliminary investigation of the allelopathic activity of 60 invasive and medicinal plants in Sri Lanka on Lactuca sativa (lettuce) and Raphanus sativus (radish). Out of 60 plants, 14 significantly reduced lettuce seedling lengths than distilled water, and 55 plants reduced radish seedling growth. In consideration of all the parameters tested, Cardiospermum halicacabum and Canarium zeylanicum Blume showed the highest phytotoxicity. C. zeylanicum (family Burseraceae), an endemic plant in Sri Lanka was selected for the isolation of phytotoxic compounds. The whole tree has a distinct fragrance bears edible seeds and has potential health benefits. This plant is used for medicinal purposes and its bark contains 3-hydroxy-12-methoxy-8,11,13-podocarpatrien-3-one and acetyl aleuritolic acid. This is the first report of the aforementioned two compounds from C. zeylanicum. These compounds exhibited phytotoxicity against lettuce. [ABSTRACT FROM AUTHOR]

The microspectrophotometer/microspectrofluorimeter was used to find the azulenes on the intact surface of 30 allelopathic and medicinal plant species growing in moderate or drought climatic conditions. Here in the maxima range of 580-620 nm, peculiar to blue pigments (azulenes), were clearly observed. The pigments were found in blue or silver leaves (needles) or plant parts (petioles, flowers and pollen). The peaks 590-610 nm, characteristic to azulenes were also observed in the absorbance spectra of ethanolic 10 min -extracts from the leaf surface, and 24 h - extracts from whole leaves. Among plants studied, the pigments were first observed in 14 terrestrial species (Anthriscus sylvestris, Lolium perenne, Petasites spurius, Phlomis tuberosa, Crambe maritima, Seseli gummiferum, Filipendula ulmaria, Echinocystis lobata, Colutea cilica, Rhus coriaria, Quercus pubescens, Pinus brutia and 2 algae (Chara vulgaris and Spirogyra sp.) use of spectral methods is recommended to search new azulene-containing species for pharmacy, agriculture and ecology. [ABSTRACT FROM AUTHOR]

Lai (Durio kutejensis Hassk. Becc) an endemic plant of Kalimantan-Indonesia leaves contain secondary metabolites as allelochemicals (alkaloids, flavonoids, saponins, phenols, and steroids). We investigated the allelopathic effects of lai leaf extract on the seed germination and early growth of weeds (Ruellia tuberosa L. and Amaranthus spinosus L.) and crops (Oryza sativa L. and Zea mays L.). We conducted two experiments: Germination bioassay and Early growth greenhouse bioassay consisting of 0 (Control), 25, 50 and 75 % leaf extracts. The leaf extracts significantly decreased the germination and early growth of both test weeds and crops: Germination (%) (100 to 26.66 %), shoot length (9.40 to 3.16 cm); germination index (3.30 to 0.36); vigour index (9.40 to 0.84); biomass 1.43 to 0.14 g); and chlorophyll a (0.45 to 0.016 mg/L), b (0.077 to 0.024 mg/L), and total chlorophyll (0.122 to 0.038 mg/L) contents. In contrast, the extract increased the germination time (3.00 to 7.00 h), mortality (0 to 40 %), and phytotoxicity (0 to 2.33 %) of test plants. Higher concentrations of plant extracts were more inhibitory to germination and early growth in all test crops. Therefore, D. kutejensis leaf extract contains a natural compound that can be potentially suitable as an allelopathic-natural herbicide. In future, the results can be used to reduce the use of chemical herbicides in crop production. [ABSTRACT FROM AUTHOR]

Field experiments were carried out at two sites to test the responses of weeds in cowpea crop to soil incorporation and surface mulching of corn residue alone or in combination with 50% rate of trifluralin herbicide. Conventional and zero tillage systems without corn residues, half of label rate and full label rate of trifluralin were included for comparison. Incorporated or mulched corn residues significantly reduced weed density and dry weight compared to conventional tillage treatment (control) at both sites. Residue incorporation and mulching plots in combination with 50% of label rate of trifluralin revealed significantly lower weed numbers and dry weight as compared to their respective controls. Soil incorporation and surface mulching of corn residue in combination with 50% rate of trifluralin achieved similar weed control and cowpea grain yield when compared to the 100% trifluralin treatment. Plots amended with corn residue showed greater levels of phenolics. Also, the periods of maximal suppressive effect against the test weed coincided with periods of maximum phenolic content, indicating the possible involvement of phenolics in weed suppression. Combination of allelopathic residues and a reduced rate of herbicides could reduce herbicide usage in agricultural systems while the weed control is not compromised. [ABSTRACT FROM AUTHOR]

Profiled metabolites from 5-donor plants; Mucuna pruriens, L. (Mc), Cymbopogon nardus L. (C), Desmodium uncinatum Jacq. DC. (D), (Zea mays, L. (Mz) and New Rice for Africa 1 (NERICA 1) were Terpenoids and Phenols. NERICA 1 (R) is a cross of Oryza sativa and Oryza glaberrima. C produced 10 terpenoids + 1 ester, R and D each released 6 Terpenoids + 3 Phenols. Mc produced 2 Terpenoids + 4 Phenols and 5 Terpenoids + 4 Phenols were profiled from Mz. We adopted a completely randomised block design with 3 replicates and eight combinations of 3 leaf+ stem+root powders namely; Mc+D+C, Mz+Mc+C, RDC, Mc+D+C, Mz+R+Mc, Mz+D+Mc, R+Mc+C and Mz+R+C, mixed with 1.5 kg soil (15, 30 and 45 %, w/w). Controls had no powders. Mixtures were placed in plastic pots and 20 seeds of Biden pilosa L. were sown in each pot. Every 2 days, 200 ml of water was applied to all treatments for 60 days. Mz+Mc controlled B. pilosa and volunteer weeds relative to R+C and C+D. Weed germination and biomass reduced with increased powder doses. Volunteer monocot weeds were more inhibited than dicots. High potential exists for functional allelopathy using allelochemicals in the donor plants to develop bio-herbicides. [ABSTRACT FROM AUTHOR]

Goat weed (Ageratum conyzoides L.) possesses several phytochemicals, which can be used environment friendly alternatives to synthetic chemical pesticides and herbicides. The major chemicals can serve as natural herbicides and pesticides to expand the range of the green biosphere. This paper: (i) overviews A. conyzoides L.; (ii) classification of A. conyzoides L.; (iii) botanical characteristics; (iv) invasiveness of A. conyzoides. (v) bioactivity of major compounds identified in Ageratum conyzoides L. and (vi) effects of A. conyzoides on different pathogens as biopesticide. [ABSTRACT FROM AUTHOR]

Allelopathy, the biochemical interaction between plants through the release of chemicals known as allelochemicals, plays a significant role in the invasion dynamics of many invasive species. This review explores the mechanisms by which allelopathy contributes to the competitive advantage of invasive plants, the types of allelochemicals involved, their modes of action, and the ecological impacts on native plant communities. We discuss the role of allelopathy in invasive species such as Ailanthus altissima (tree of heaven), Eucalyptus spp., and Fallopia japonica (Japanese knotweed), highlighting current research and identifying gaps for future study. [ABSTRACT FROM AUTHOR]

We evaluated the allelopathic potential of Ageratum conyzoides L. aqueous leaf extracts on germination and growth of Solanum lycopersicum L. (tomato), Zea mays L. (corn) and Lactuca sativa L. (lettuce). Total phenolic content (TPC) of the soil rhizosphere was determined by spectrophotometry method. We also investigated the habitat attributes (e.g., canopy openness and leaf area index (LAI)) of A. conyzoides infested region. Results revealed that aqueous leaf extracts had both inhibitory and stimulatory effects on the germination, plumule length and radicle length of crops. All extract concentrations inhibited the germination of Z. mays and L. sativa seeds, but no effects on S. lycopersicum, except at 50 gL-1. Conversely, plumule and radicle lengths were stimulated in S. lycopersicum and L. sativa for majority of extract concentrations but they were inhibited in Z. mays. The inhibitory allelopathic effects of A. conyzoides were maximum in Z. mays (i.e., S. lycopersicum < L. sativa < Z. mays). TPC values in invaded soil were 0.046 g/L and 0.48 g/L with gallic acid and catechol, respectively. This study showed that the presence of allelochemicals in A. conyzoides invaded soil, which potentially influenced the crops, thereby validating the 'novel weapon (NW) hypothesis'. The recorded values of habitat attributes were associated with the successful spread of A. conyzoides and hence, its allelopathic effects on test crops. [ABSTRACT FROM AUTHOR]

Pollen allelopathy positively or negatively influences the fertilization of plants and has great significance from ecological perspectives. The release of allelochemicals from foreign pollen grains on the stigmatic surface obstructs the processes of fertilisation, seed establishment, tube formation, stigma receptivity, and pollen germination. So far, pollen allelopathy has received little attention and still a growing topic of ecological studies. Therefore, a literature review was undertaken to provide the valuable information regarding the ecological and reproductive implications of pollen allelopathy, heterospecific pollen transfer mechanisms of allelopathic anemophilous and entomophilous plants, and to shed light on the biochemistry and mode of action of allelochemicals. The majority of entomophilous plants share pollinators within communities, and heterospecific pollen transfer by both anemophilous and entomophilous plants causes a reduction in their reproductive success, like pollen germination, tube development, ovule maturation and seed set. For detailed study of pollen allelopathy, a few factors should be considered like metrological parameters, distance travelled by pollen, pollen viability, and stigma receptivity during foreign pollen deposition. A thorough understanding of the biochemical and enzymatic processes that occur after foreign pollen is deposited on the native stigma will open up new perspectives on plant reproduction. Pollen allelochemicals, which have important significance as biocontrol agents for the maintenance of agroecosystems, need to be identified and characterised. The ecological aspects of pollen allelopathy may be well understood with the help of field studies. [ABSTRACT FROM AUTHOR]

The allelopathic potential of rizobacteria was investigated on root rot/wilt and on the growth of Citrus reticulata Blanco, Citrus limon Burmann and Citrus sinensis [L.] Osbeck seedlings. The highest means of incidence of disease and severity were recorded for lemon transplants (38.6 and 27.6.0 %, respectively) followed by mandarin transplants (34.5 and 23.8 %), while orange transplants revealed the lowest means (24.3 and 13.9 %). The most frequently fungi isolated from rotted roots of the citrus transplants were Fusarium oxysporum, F. solani and F. proliferatum. In pathogenicity tests, all the tested fungi were pathogenic to mandarin, lemon and orange transplants. The effect of plant growth promoting rhizobacteria (PGPR) individually and/or mixed when used as a soil drench treatment varied in reducing root rot/wilt incidence and severity under greenhouse conditions compared with control. The mixed culture of PGPR recorded the highly significant reduction in severity of root rot/wilt disease as compared to when the PGPR strains were used individually. On the other hand, the mixed culture of PGPR recorded the highest protection against infection with F. oxysporum (95-96 %) followed by F. solani (93-94 %) and F. proliferatum (89-91 %) in case of mandarin, lemon and orange transplants. Also, all treatments significantly increased plant height (cm), number of leaves transplanting-1, leaf area (cm2), fresh and dry weights transplanting-1(gm) compared with control treatment. This study indicated that soil drenched with PGPR strains can be used as a safe control measure of the disease in citrus transplants and as a stimulant of vegetative growth parameters. [ABSTRACT FROM AUTHOR]

Majority of cash crops have the problem of continuous cropping in the planting process, especially the genus Panax. A series of diseases occur in the process of ginseng planting, which will aggravate the obstacle of continuous cropping, directly lead to the significant decline of ginseng yield and quality, and seriously affect the development of ginseng planting industry. Taking two main species of Panax plants, namely Panax ginseng C. A. Mey and Panax notoginseng (Burkill)F.H. Chen ex C.H., this paper explains the three main factors affecting their continuous cropping, namely (i). Allelopathic autotoxic substances, (ii). Soil microbial community and (iii). Soil physico-chemical properties. The main methods to overcome continuous cropping obstacles were listed, including (i). Biological breeding, (ii). Soil sterilization, (iii). Establishment of reasonable farming system, (iv). Use of microbial fertilizer and (v). The directions of future research were discussed to provide scientific reference for the cultivation and management of alleviating or overcoming the obstacle of continuous cropping of ginseng. [ABSTRACT FROM AUTHOR]

We investigated the effects of Alfalfa (Medicago sativa L.) and Bermudagrass (Cynodon dactylon L.) extracts concentrations on callus induction and rye (Secale cereale L.) embryo regeneration and growth of rye seedlings in both greenhouse and in-vitro conditions. Immature rye embryos were used as explants for generating callus, and water extracts of alfalfa and bermudagrass were added to the environment with a concentration of 5, 10, 15, 20, 25 and 30 %. This extract was also used in the regeneration period. The use of 25 and 30 % alfalfa extracts stopped callus induction and its components. The application of bermudagrass extract with a concentration of 30 %, reduced rye callus induction to 50 %. Alfalfa extract concentrations of 20 and 25 %, respectively caused a reduction of 35 and 75 % in callus fresh weight in comparison with the control conditions. Applying 25 and 30 % concentrations of bermudagrass extract led to a reduction of 68 and 80 % respectively. Alfalfa extracts with 15, 20 and 25 % concentrations caused reductions of 40, 63 and 69 % in rooting. The 30 % concentration of M. sativa extract stopped rooting in rye callus. Concentrations of 15, 20, 25 and 30 % caused reductions of 31, 50, 55 and 81 % in the shooting of rye callus, respectively. The results indicate that alfalfa extract had greater effect on rooting, and the bermudagrass extracts had greater effect on shooting. The analysis of the results shows that Alfalfa and bermudagrass extracts have a strong allelopathic effect, which can be used in the production of herbicides of natural origin. [ABSTRACT FROM AUTHOR]

We evaluated the effects of Taraxacum officinale L. and Ricinus communis L. on growth and physiology of sunflower and maize plants. Seeds of sunflower (cv Parson 3) and maize (cv TP 1217) were surface sterilized and soaked in 0.3 % and 0.5 % aqueous extracts of T. officinale L. and R. communis L. prior to sowing, plants were grown in pots under natural conditions. Fresh and dry weight of shoot and root, chlorophyll, carotenoids, protein, proline, phenols and flavonoids and phytohormones contents in leaves of sunflower and maize were determined. The activities of antioxidant enzymes (Superoxide dismutase (SOD), Peroxidase (POD) and defense related enzymes viz. Phenylalanine ammonia-lyase (PAL) and Polyphenol oxidase (PPO) were also recorded in leaves of maize and sunflower at vegetative phase. Phytohormones indole acetic acid (IAA), gibberellic acid (GA) and abscisic acid (ABA) were detected in T. officinale L. and R. communis L. Extract of T. officinale L. and R. communis L. significantly enhanced the shoot biomass in maize and sunflower as compared to control. Proline, phenolics, flavonoids, protein, chlorophyll, carotenoids and terpenoids content of fresh leaves were enhanced in all the treatments as compared to control. Activities of PAL, SOD, PPO and POD were also enhanced. Among all the treatments 0.3 % aqueous extract of T. officinale L. and 0.5 % aqueous extract of R. communis L. were more effective in sunflower and maize plants. The extracts of T. officinale L. and R. communis L. may be implicated to improve the growth and defensive system of maize and sunflower and induce tolerance to stresses by augmenting osmoregulation and enhancing the antioxidant and defense related enzymes. [ABSTRACT FROM AUTHOR]

The use of allelopathic rice varieties has recently been increasing due to their safety and sustainability in weed management. This study aims to investigate the allelopathic effects of rice varieties developed through N-methyl-N-nitrosourea (MNU) mutation on the growth of lettuce and barnyard grass, as well as to establish the relationship between grain quality and the allelopathy of rice plants. Rice straw, husk, and grain samples of rice varieties K1, K2, K3 and K4 were collected and extracted with methanol. The methanol extracts were investigated for antioxidants, total phenolic content (TPC), total flavonoid content (TFC) and the presence of momilactones A (MA) and B (MB). They were subjected to high-performed liquid chromatography (HPLC) coupled with a UV detector and tested for their allelopathic potential. MA and MB were quantified using Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS). The results revealed that mutant varieties exhibited higher antioxidants and TPC in both the grain and straw. Additionally, the mutant varieties increased the presence of MA and MB in the straw and husk. The straw exhibited stronger inhibitory effects compared to the husk. The straw samples from mutant rice varieties exhibited stronger inhibition towards lettuce (Lactuca sativa L.) and barnyard grass (Echinochloa crus-galli L.). Both the straw and husk strongly inhibited seed germination, shoot length and root length in barnyardgrass compared to lettuce. The inhibition was more pronounced in root growth than shoot growth. Rice varieties with higher allelochemical contents in their straw and husk exhibited stronger allelopathic effects. These findings suggest that rice varieties developed through the MNU mutation exhibited higher allelopathic activity compared to their wild-type cultivars. Therefore, the MNU mutation shows promise for breeding allelopathic rice varieties, which can help reduce the reliance on synthetic herbicides for weed control. [ABSTRACT FROM AUTHOR]

We characterized the chemical compounds present in the extract of dry leaves from Duranta erecta L. using ESI-MSn mass spectrometry and assessed their phytotoxic potential on Lactuca sativa L.. The extraction process involved exhaustive extraction with 50% ethanol, and the resulting extracts were subsequently dried through lyophilization. Solutions of 2.5, 5, 10, 20, and 40 mg/mL concentrations were prepared from the dried extracts to investigate their allelopathic effects on L. sativa, focusing on germination, germination speed, root elongation, shoot length, and fresh biomass. Statistical analysis was performed using Analysis of Variance, and means were compared using the Scott-Knott test (p < 0.05). The ESI-MSn analysis identified a total of 20 compounds in the extract, with 12 of them being reported for the first time in Duranta sp. Our findings suggest that D. erecta possesses allelopathic potential, as evidenced by its cytotoxicity, mitodepressive effects, and phytotoxicity on germination and morphological parameters in the bioassay conducted with L. sativa. [ABSTRACT FROM AUTHOR]

We investigated the allelopathic effects of A. philoxeroides stem on E. crassipes and found reduction in plant height (32 to 61 %), number of leaves (13 to 38 %), number of branches (20 to 43%) and fresh weight (63 to 73 %). The E. crassipes plants got dried in cisterns treated with A. philoxeroides. The allelochemicals present in A. philoxeroides plants were inhibitory to water hyacinth. The allelopathic leachate of A. philoxeroides caused maximum decrease in growth of E. crassipes, due to presence of alkaloids and phenols. In control, there were no detrimental effects on growth of E. crassipes. [ABSTRACT FROM AUTHOR]

We investigated the effects of Azadirachta indica Juss. agroforestry tree aqueous leaf extract on seed germination and seedling growth of Oryza sativa L. and Zea mays L. The allelopathic effects of 0 (control),10,20,30,40 and 50 % concentrations of A. indica aqueous leaf extracts were determined on germination, growth, synthesis of photosynthetic pigments and biochemical constituents (starch, protein and aminoacid) of maize and rice seedlings. These extracts had both inhibitory and stimulatory effects on O. sativa and Z. mays at different stages of plant growth and development. Seed germination decreased with increasing concentration of leaf extracts from 20 % to 50 %. At lower concentration of 0 % (control) the shoot length, vigour index, and total chlorophyll were significantly increased. The inhibitory and stimulatory activity depended on the extract concentrations, higher concentration strongly inhibited the pigments, vigour index, seedling length, starch, protein and aminoacid. We found that the A. indica extract had water-soluble allelochemicals which significantly reduced the growth of O. sativa and Z. mays. [ABSTRACT FROM AUTHOR]

Molisch in 1937 coined Allelopathy from two Greek words, 'allelo' (means two organisms) and 'pathos' (means harm). The term defined as plant released metabolites into environment through ecological processes (volatilization, leaching, root exudation and decomposition of plant debris in soil), resulting in detrimental effects on understory or neighboring plants sharing the same habitat. This essay aimed to describe the allelopathy researches in the past, present and future, dealing with the allelopathy in natural and managed ecosystems and the allelochemicals in biomedical researches. It has 3-parts: Part I. Role of allelopathy in natural ecosystems, Part II. Allelopathy in managed ecosystems (Role in agroecology and sustainable agriculture) and Part III. Isolation and identification of allelochemicals, which exhibit bioactivities (anti-microbial, anti-hepatitis, anti-cancers and anti-diabetes to be potentially used to cure human diseases. For example, many natural products, such as flavonoids, terpenoids and alkaloids isolated from Rhododendron and Alstonia, exhibited anti-microbial activity against several microorganisms (Enterococcus faecalis, Pseudomonas aeruginosa and Klebsiella pneumoniae). The allelochemicals, ursolic acid, betulinic acid, botulin and 2,3,28-lup-20(29)-ene triol isolated from A. scholaris, showed the proliferative activity of non-small-cell-lung cancer (NSCLC). The ursolic acid isolated from R. formosanum also showed pronounced growth inhibition of NSCLC, in addition, cinnamtannin D1 also exhibited anti-cancer efficacy that induced G1 arrest and autophagy via the mTOR pathway inhibition and ERK 1/2 pathway activation. Several Solanum species are traditionally used to treat HBV infection. In Cucurbitace family, fruits and stems of Momordica charantia (called bitter melon) possess anti-diabetic and anti-lipedemic compounds. This essay also describes the mode of actions of the aforementioned allelochemicals in the metabolomic pathway of anticancer or antimicrobial activities. The authors create a new scientific term called "Allelochemicology", which hopefully, inspires young scientists in life sciences to explore this field, to solve the most difficult tasks on ecology, sustainable agriculture, pharmaceutical and medicine that can be beneficial to human beings for reaching the Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

Allelopathy Journal is the official publication of 'Allelopathy Books' that promotes allelopathy research and publish researches related to plant sciences and health sciences. This study aimed to present an insight about the researches published in this journal, to help the Authors, Readers and Editorial team to understand the journal in depth. We analyzed the scholarly publications published in the Allelopathy Journal, their Citations, focussing on other aspects such as Publication output, Citation analysis, Co-authorship patterns, Collaboration networks, Research productivity, Research topics and International collaboration. This study is useful to identify emerging trends and evaluate research impact. The data for the study was extracted from the Scopus Database for the period from 1996 to 2022. The results showed that the journal has published 1209 papers during this period, which received 9826 citations with an average of 8.13 citations per paper. F.Z. Wu was the most prolific author with 22 papers receiving 127 citations and Prof. S.S. Narwal, with second highest papers in the journal, received the highest number of citations (242). China was the most productive country with 425 papers in the journal, followed by India (243 papers). The Chinese Academy of Sciences was the most productive institute in the journal and published 67 papers with 678 citations. A total of 4870 authors have appeared in 1209 papers with 0.91 degree of collaboration and a collaboration index of 4.03. Thematic maps indicated that the topics represented by keywords such as "Distribution", "Habitat", "Essential Oil", "Lettuce", "Morphology," have potential importance for future research. [ABSTRACT FROM AUTHOR]

Allelopathy can seriously affect the growth and vitality of plants and microorganisms. We analyzed the effects of Willow (Salix matsudana Koidz) root exudates on soil bacterial diversity to explore the interactions between plants and soil microorganisms. A total of 18 compounds were identified from the root exudates of S. matsudana variety Yanjiang by GCMS in which the butylacetate content was maximum (72.20 %). Soil was treated with S. matsudana root exudates and genomic DNA of microorganisms was extracted and analyzed by 16s-rDNA sequencing. A total of 374 bacterial species were identified, 91 % of which were uncultured. Uncultured&lowbar;bacterium&lowbar;c&lowbar;subgroup&lowbar;6 was the dominant bacteria in both treated and control samples. Two species of uncultured&lowbar;bacterium&lowbar;f&lowbar;Acetobacterales&lowbar;incertae&lowbar;sedis and uncultured&lowbar;bacterium&lowbar;f&lowbar;Lachnospiraceae were found only in the treated sample, whereas, two species of Kofleria&lowbar;flava and uncultured&lowbar;bacterium&lowbar;f&lowbar;Enterobacteriaceae were present only in the control sample. The abundance of most species differed between the treated and control bacterial communities, e.g., the abundance of uncultured&lowbar;bacterium&lowbar;f&lowbar;Amb-16S-1034 was 7.22 times higher in the control than in the treated sample and uncultured&lowbar;bacterium&lowbar;g&lowbar;Bacteroides was 6.65 times higher in the treated community than in the control. Functional analysis showed that bacteria in the treated sample were enriched for some disease-resistant and cellulose-decomposing strains. The results demonstrated that willow root exudates can change the soil microbial community structure, which might correspondingly affect the plant growth. [ABSTRACT FROM AUTHOR]

Molish in 1937 coined Allelopathy from two Greek words, 'allelo' (means two organisms) and 'pathy' (means harm). The term defined as plant released metabolites into environment through ecological processes: volatilization, leaching, root exudation and decomposition of plant debris in soil, resulting in detrimental effects on understorey or neighbouring plants sharing the same habitat. This essay aimed to describe the allelopathy researches dealing with the allelopathy in natural and managed ecosystems in the past, present and future. The allelopathy plays an important role in managed ecosystems, particularly in agricultural productivity. The yield reduction of rice (Oryza stiva L.) in the second crop season was 25 to 50 % lower than the first crop season in Taiwan. This phenomenon was designated as auto-intoxication, which is another phase of allelopathy. The potential of allelochemicals are often modified by environmental stresses (temperature, soil pH, drought, nutrients deficiency, light and physiological or biochemical interactions) under varied environmental conditions. The action modes of allelochemicals on the structure and function of plants are via physiological and molecular interactions. Allelochemicals released from plants, microorganisms, or algae can be used as agro-chemicals (Herbicides, fungicides, nematicides and anti-pathogens), these are environmental friendly for sustainable agriculture. For example, the win-win strategy of pasture-forest intercropping results in the kikuyu grass suppresses the weed growth due to the allelopathic effects of kikuyu grass, but is good for the regeneration of chinese fir. Furthermore, the mechanisms of allelochemicals action on crops are discussed. The allelochemicals cover very broad aspects of chemical interactions among organisms, thus, the fundamental studies of natural products from organisms need trainings in multi-disciplinary sciences viz., Biology, ecology, biochemistry, organic chemistry, molecular biology, soil science and earth sciences. The authors coined a new scientific term called "Allelochemicology", which hopefully, inspires young scientists in life sciences to explore this field to solve the most difficult tasks in ecology, sustainable agriculture, pharmaceutical and medicinal applications. The research finding of allelopathy, indeed, can be beneficial to human beings in reaching the Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the allelopathic effects of abscised plant parts of Terminalia arjuna on germination, growth, and physio-biochemical processes of Triticum aestivum L. Different doses of plant material obtained from fruits (F100 and F50), branches (B100 and B50), leaves (L100 and L50), and the mixture of all plant parts (A100) were applied to the seedbeds of two varieties of T. aestivum, DPW-62150 and DBW-17. It was observed that both the varieties differed in the intensity of response towards the treatments measured in terms of seed germination, shoot length, root length, dry weight, vigour index, tolerance index, total chlorophyll, nitrogen and organic carbon. The mixture of all the plant parts of T. arjuna stimulated most of the studied parameters and wheat variety DBW-17 performed better as compared to DPW-62150. A total of 49 allelochemicals were identified in the GC-MS analysis, of which 28, 28, and 30 were present in the fruit, branch and leaf powder, respectively. It can be inferred from the study that T. aestivum, particularly variety DBW-17, can be successfully intercropped with T. arjuna. However, further field studies should be undertaken on a wider scale to validate the results of this study. [ABSTRACT FROM AUTHOR]

This essay aimed to describe the allelopathy researches in the past, present and future, dealing with the allelopathy in natural and managed ecosystems. The unique allelopathic patterns of chaparral, coniferous forests, fern vegetations, tropical and subtropical vegetations from forests to grassland communities and introduced and invasive species are presented. The aforementioned species exhibit unique inhibitory effects on the growth of the adjacent plants or understory species. The allelopathy plays an important role in vegetation dominance and succession. The potential of allelochemicals are often modified by environmental stresses (soil pH, drought, nutrients deficiency, light etc.) and physiological or biochemical interactions. The allelopathic interactions among the aquatic organisms, such as algae, seaweeds and coral are also presented. Of which, the formation of algae red-bloom and the effects of global climatic change on ocean acidification to marine organisms is also presented. The modes of action allelochemicals on the structure and function of plants via physiological, molecular interactions are expressed. The allelochemicals cover very broad aspects of chemical interactions among organisms, thus, the fundamental studies of natural products from organisms need trainings of multidisciplinary sciences. The authors create a new scientific term called “Allelochemicology”, which hopefully, inspires young scientists in life sciences to explore this field to solve the most difficult tasks in Ecology, Sustainable Agriculture, Pharmaceutical and Medicine that can be beneficial to human welfare in reaching the Sustainable Development Goals. This eassy covers the research in the past, present and future in 3-parts: Part I. Natural Ecosystems, Part II. Managed Ecosystems and Part III. Allelochemicals use in Pharmaceutical Agents and Biomedical Sciences. [ABSTRACT FROM AUTHOR]

Ageratum conyzoides L. (family- Asteraceae), called billygoat, is an annual aromatic plant. It is an invasive weed in tropical and subtropical regions of the world. It contains a wide variety of secondary metabolites with many biological activities [antibacterial, antifungal, antiinsecticidal and herbicidal]. This review describes the taxonomy, description, botanical characteristics, future research lines and the herbicidal potential of its secondary metabolites for weeds management based on literature from 1999-2021. Its herbicidal potential varies with extract sources, solvent types, phytochemical test methods, target weed species and plant interferences. Based on the review, A. conyzoides extract and its constituents may act as a promising biosource for formulations of effective bio-herbicides. [ABSTRACT FROM AUTHOR]

In pot culture, we investigated the allelopathic effects of 3-donor plants [Artemisia fragrans Willd., Tanacetum chiliophyllum (Fisch. & E.Mey. ex DC.) Sch.Bip. and Teucrium polium L.] on establishment of sown Medicago scutellata (L.) Mill. in shrubland invaded by grasses. We used 4-concentrations (0, 5, 10 and 20 %) of aqueous extracts of 3 -donor plant spp. (A. fragran, T. chiliophyllum and T. polium) on germination and seedlings growth of recipient M. scutellata. The seeds germination of M. scutellata decreased with increasing concentrations of aqueous extract. The T. chiliophyllum 5 % aqueous extract was least inhibitory to seeds germination of M. scutellata. While the A. fragrans 20 % aqueous extract was most inhibitory and significantly delayed the seeds germination than control. Seed vigour index in T. chiliophyllum aqueous extracts was significantly higher than other treatments and control. T. chiliophyllum 5 % aqueous extract stimulated the root length. The A. fragrans aqueous extracts were most inhibitory to plant biomass, leaf number and leaf area. The inhibitory effects of aqueous extracts of all donor plants on M. scutellata seeds germination and seedlings growth increased with increasing aqueous extracts concentrations i.e. concentration dependent. The 20 % aqueous extract of A. fragrans was most inhibitory, while, 5 % aqueous extract of T. chiliophyllum were least inhibitory. The inhibitory alleloopathic effects of donor spp ranked as A. fragrans, T. polium and T. chiliophyllum. Therefore, it is necessary to consider the allelopathic effects of introduced species on rangeland plant spp. Therefore, for sowing ofM. scutellata, the under story canopy of T. chiliophyllum is best. Moreover, the sites with low or moderate density of T. chiliophyllum and T. polium have the highest chances of success to reclaim shrubland. Whereas in areas with abundant A. fragrans, the sowing should be done cautiously due to its very drastic inhibitory effects. Additionally, the research on success of other forage species to restore the A. fragrans dominated rangelands is suggested. [ABSTRACT FROM AUTHOR]

We investigated the allelopathic effects of aqueous extracts of shoots (leaf, stem, fruits) of Cucumis melo L weed on the growth, photosynthetic, and antioxidant system of Brassica napus and Sinapis arvensis weeds. The fruit, leaf, and stem aqueous extracts of Cucumis melo L were sprayed at 0, 2.5, 5 and 10 % concentrations on the plants of Brassica napus and Sinapis arvensis at rosette stage and after one month the effects on plants were studied. The higher concentration of Donor Cucumis melo aqueous extracts, decreased the growth parameters in recipient Brassica napus and Sinapis arvensis weeds. The higher concentrations of Cucumis melo extracts increased the phenolic compounds and decreased the flavonoid compounds in both test plants and these changes were higher in Brassica napus than in Sinapis arvensis. The aqueous extracts of leaves, stems and fruits of Cucumis melo analyzed by GC-MS contained 30, 23 and 12 allelochemical compounds, respectively. These allelochemical compounds in extracts of leaf, stem and fruit of Cucumis melo influenced the morpho-physiological characteristics of Brassica napus and Sinapis arvensis weeds. [ABSTRACT FROM AUTHOR]

We studied the allelopathic potential of above-ground vegetative shoots of 3-cultivars ('Ani', 'Bila', and 'Nandu') of Poa pratensis and their effects on the initial growth and development of 6-Acceptor plants spp (Agrostis capillaris cv. Niwa, Festuca arundinacea cv. Asterix, Festuca ovina cv. Espro, Festuca rubra cv. Areta, Lolium perenne cv. Stadion and P. pratensis cv. Bila) present in grass lawn community. Aqueous extracts from shoots of P. pratensis 3-cultivars were tested in Petri dishes on filter paper. Whereas, the dried chopped leaves of P. pratensis cultivars were incorporated in pots containing sand for assay. The phenolics and flavonoids in the plant materials were analyzed by liquid chromatography. The allelopathic potential of Donor P. pratensis cultivars on the acceptor plants were correlated with the leaf contents of flavonoids and phenolic acids and followed the Order: 'Ani' > 'Nandy' > 'Bila'. The allelopathic potential of Donor cultivars on the Acceptor plants in Petri dish Bioassays was higher than in Pot assays. Aqueous extracts were more inhibitory to root growth than to seed germination and shoot growth. In contrast, in Pot assay allelopathic substances released from the decomposing cut leaves were more inhibitory to sprouting seeds than shoot elongation. The A. capillaris was most sensitive to allelopathic effects of P. pratensis cultivars followed by F. rubra and P. pratensis. The plants of F. arundinacea and L. perenne were least sensitive. With this in mind, it is advised to remove the cut grass from the lawn surface. [ABSTRACT FROM AUTHOR]

Echinochloa crus-galli (Barnyard grass) seriously damages crops in China. It has become resistant to many herbicides, hence, new and effective control measures need to be found. We did bioassay to find the herbicidal potential of 11-plant species essential oils on barnyard grass. The essential oils ofArtemisia argyi Lévl. et Van. (Green Wormwood oil), Curcuma zedoaria (Christm.) Rosc. (Turmeric oil) and Pogostemon cablin (Blanco) Benth. (Patchouli oil) effectively inhibited the growth of barnyard grass. The green wormwood oil had the most potent herbicidal effects (EC50=0.0107 g/mL). After treatment with green wormwood oil, the activities of defence enzymes [catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD)], dramatically increased 8 h after-treatment, and then decreased to initial levels within 72 h. Gas chromatography-mass spectrometry (GC-MS) results revealed that borneol and eudesmol are two major components of green wormwood oil. The herbicidal activity assays revealed that eudesmol was more potent than borneol (Borneol, EC50=0.0865 g/mL; Eudesmol, EC50=0.0134 g/mL). The experiments indicate that green wormwood oil is a valuable raw material for developing new eco-friendly herbicides for agriculture. [ABSTRACT FROM AUTHOR]

Allelopathic effect can lead to continuous cropping problem in plants. Mixed sowing of different species/varieties may overcome this problem. Two turfgrass (Festuca arundinacea Schreb.) varieties Millennium2 and Arid3 were studied for their growth potential in mixture and effects on growth of lawns. The results showed that the mixed sowing proportion had significant impact on the growth of turfgrass. The main variety 0 showed improved physiological indices and better growth in mixture ratio of 4:1. The variety Millennium2 was more sensitive to mixture than Arid3. GC-MS analysis showed that the root aqueous extracts of Millennium2 and Arid3 contained 15 and 22 allelopathic compounds, respectively, and the content of 1,1-diethoxy-3-methylbutane was highest. Both varieties shared 9-chemicals (1,1-Diethoxybutane, 2-methylpentanoyl 2-methylpentanoate, 1,1-diethoxy-3-methylbutane, octamethylcyclotetrasiloxan, 6-ethyl-2-methyloctane, 5-methylundecane, 4,6-dimethyldodecane, henicosane and icosane), while Arid3 and Millennium2 individually contained 13 and 6 unique compounds, respectively. Thus, the selection of compatible species/varieties and their suitable proportion is very important for ideal mixture to improve the appearance of lawn and ecological effects. [ABSTRACT FROM AUTHOR]

Eucalyptus provides various timber, firewood, landscaping and pulp for paper. Eucalyptus species have been introduced in many countries due to their fast growth, easy management and environmental tolerance. Allelopathy is major cause of biodiversity reduction in Eucalyptus plantations. However, no systematic work has been done on this allelopathic plant and its allelopathic effects on other recipient plants. In this review, allelopathic effects of 75-Eucalyptus species [7-Major Eucaluptus spp: (E. camaldulensis, E. citriodora, E. globulus, E. grandis, E. grandis x E. urophylla, E. tereticornis and E. urophylla) and 68-minor investigated species] are reported. The allelopathic effects of Eucalyptus sp. on acceptors (e.g., plants, crops and microorganisms) have been summarized and the recent progresses in the allelopathic research and future research prospects are discussed. It provides a quick reference to the Eucalyptus spp, their allelopathic effects and uses. It also provides beneficial informations on use of Eucalypus sp., in medicine and agriculture, and suggests how to best manage a forest ecosystem by avoiding allelopathic inhibitory effectgs on other plants. [ABSTRACT FROM AUTHOR]

Itchgrass [Rottboellia cochinchinensis (Lour.) W.D. Clayton] is a C4 annual upland grass, which is self-pollinated and invades disturbed and agricultural areas in more than 40 countries in tropical and subtropical regions of the world. The plant exerts high competition for row crops due to its high tillering capacity. Conversely, itchgrass is an allelopathic plant, which is often used as a mulching material for weed control in vegetable fields in Chae Hom district, Lampang Province, Northern Thailand. Itchgrass plant mulch can conserve soil moisture, minimize soil erosion and suppress other weed species. In this review, the available published literature has been compiled to understand the mechanism of allelopathic action of this important grass and to highlight its significance in the cropping systems. It has been noted from the literature that the allelochemicals released from itchgrass in the soil can adversely influence the germination of some adjacent weeds and test crops, causing a growth reduction of seedlings. Various authors have concluded that transp-coumaric acid (trans-4-hydroxycinnamic acid) is the major allelochemical present in itchgrass. Additionally, two active substances have been reported to be isolated from n-hexane crude extracts of the itchgrass aerial part and has been identified as linoleic acid (9,12-octadecadienoic acid) and linolenic acid (9,12,15-octadecatrienoic acid). It can be concluded that both direct and indirect allelopathic effects are involved in facilitating succession of itchgrass plant. Better understanding of its allelopathic potential will provide a basis for improving the non-chemical weed management strategies in vegetable fields for sustainable agriculture. [ABSTRACT FROM AUTHOR]

Soil sickness is a serious problem to establish new fruit orchards at the old orchard site. It is a complex soil sickness syndrome that reduces the plant growth, survival and yield of replanted trees. Various factors are responsible for soil sickness viz., (i) biotic factors i.e. rhizospheric microflora (bacteria, fungi, actinomycetes, nematodes and their interactions) and (ii) abiotic factors (phytotoxins, nutrient imbalance, low or high pH, soil structure and lack of excess soil moisture). In many cases, autotoxins may enhance soil-borne diseases by predisposing the roots to infection by soil-borne pathogens through direct biochemical and physiological effects. It is not easy to prevent the soil sickness problem because of its exact etiology and complex nature of problem and different biotic and abiotic factors are associated with it. The nature and intensity of incidence are variable from region to region and country to country and there is a lack of quick diagnostic methods. It cannot be controlled with one method and require integrated management practices. This review outlines the current knowledge on methods to reduce the negative effects of soil sickness in fruit orchards, which may be a promising strategy to improve the growth and yield of fruit trees in sick soils. [ABSTRACT FROM AUTHOR]

Generally, the laboratory assessment of allelopathy involves the determination of germination rates and measurements of the roots and shoots elongation of receptor plant species exposed to an allelochemical source (e. g. extracts, leachates, root exudates) or a purified allelochemical. However, these assessments are time consuming and laborious. In the present study, a new centrifuge tube agar profile method (CTAP) was introduced to determine the allelopathic effects of aqueous extracts from 30 plant species on lettuce (Lactuca sativa L.). The results demonstrated that the water extract of Melilotus officinalis (L.) Pall. had the strongest inhibitory effects on lettuce. Water extract of M. officinalis (L.) Pall. was analyzed by GC-MS, and the allelopathic effects of coumarin on 5-plant species (Lactuca sativa L., Raphanus sativus L., Raphanus sativus L., Lycopersicon esculentum Mill., Lactuca sativa L., and Brassica campestris var. chinensis) were determined by CTAP. The exposure of coumarin at 100 mg·L-1 for 2 days stimulated the growth of radish (Raphanus sativus L.). This study introduces a new method for the rapid determination of allelopathic potential of plants and allelochemicals. [ABSTRACT FROM AUTHOR]

Soil sickness of ginseng (Panax ginseng C. A. Mey.) has become a major limiting factor in ginseng cultivation. We found that Total Ginsenoside in Ginseng Root (TSPG) significantly decreased the activities of soil urease, acid phosphatase and laccase. Its high concentration of TSPG (10.00 mg L-1) significantly reduced the activity of soil sucrose. Besides, the TSPG can inhibited the growth of ginseng and increased the incidence of disease. Therefore, allelopathic effects of TSPG may be one of the main causes of Soil Sickness in ginseng. [ABSTRACT FROM AUTHOR]

Facilitative interactions occur between the plants in intercropping systems, however, the underlying allelopathy mechanisms are poorly understood. We determined the effects of potato-onion (Allium cepa var. agrogatum Don.) intercrop on root morphology of tomato (Lycopersicon esculenum L.) through volatile organic compounds (VOCs). There were four treatments as (i) Tomato/tomato without VOCs interaction (-TT), (ii) Tomato/tomato with VOCs interaction (+TT, control), (iii) Potato-onion/tomato without VOCs interaction (-OT) and (iv) Potato-onion/tomato with VOCs interaction +(OT) in glasshouses. As compared to tomato, VOCs from potato-onion significantly increased the number of root tips total length but decreased the root diameter of tomato, however significantly the increase the tomato root length (0-0.5 mm mean diameter). These results indicated that the tomato root morphology has influenced by aboveground secreted VOCs from neighboring plants in potato-onion intercropping system. [ABSTRACT FROM AUTHOR]

We studied the inhibitory effects of allelochemicals extracted from celery (Apium graveolens L.) rotten roots and rhizosphere soil on Fusarium oxysporum f. sp. cucumerinum (FOC). The allelochemicals were extracted and separated by column chromatography from the acetone extracts of celery rotten roots and rhizosphere soil. After extraction each fraction was mixed with potato dextrose agar (PDA) culture medium and then inoculated with FOC. The best fraction was screened by measuring the colony diameter and its effects on FOC was determined by evaluating the activities of antioxidant enzymes. The allelochemicals of best fractions were detected using GC-MS. The best fractions obtained after second run in column chromatography were labeled as RRA32, RRA38, RRA101, RRA102 and RRSA55, RRSA56, RRSA105, RRSA106 and they had allelopathic potential of 29.68 %, 31.97 %, 40.38 %, 41.55 % and 29.51 %, 29.47 %, 29.30 % and 32.85 % respectively. The antioxidants enzymes (peroxidase, catalase and superoxide dismutase) activities were significantly lower in treated FOC than control. Using the 8-best fractions, the GC-MS analysis yielded, total 47 compounds viz., 7 organic acids, 17 esters, 1 phenol, 1 alcohol, 1 aldehyde, 5 nitrogen-containing compounds and 2 carbides. [ABSTRACT FROM AUTHOR]

Udo Blum had a teaching and research career of 34 years. His primary role was teaching, advising, and mentoring undergraduate and graduate students. He authored or co-authored research publications on plant-plant allelopathic interactions, air pollution biology, and salt marsh biology. He retired in 2002 and has subsequently written a three-volume retrospective analysis of his research on plant-plant allelopathic interactions involving phenolic acids. His primary research goals were to understand: (i) how cinnamic and benzoic acids released from plants into the soil affect sensitive seedlings and soil and rhizosphere microorganisms, (ii) how phenolic acids are distributed and partitioned in seedling-microbe-soil-sand systems and (iii) how their effects on sensitive seedlings are modified by abiotic soil factors (soil pH, soil moisture, soil nutrients, presence of other organic compounds) and soil processes (microbial utilization and soil sorption) in laboratory and field model systems. In 1999 he received the Molisch Award from the International Allelopathic Society for his research contributions to our understanding of Plant-plant allelopathic interactions. [ABSTRACT FROM AUTHOR]

Plant allelopathy is a biological phenomenon in which plants adapt to defend against the pests (weeds, insects, nematodes and pathogens) adverse environment. It is one of the hotspots in Ecology and Agronomy. In this paper, we have retrieved from the Web of Science (WoS) SCI-E database the allelopathy-related studies (1960-2019). The Annual Number of Publications, Authors, Countries, Institutions, Journals and Keywords were analyzed by the bibliometric method to determine the research trends and hotspot changes in this field over the past 6 decades. From 1960-2019, the WoS database included 4,114 studies in the field of plant allelopathy. During this period of 60 years, the number of publications has gone through three stages: (i). Initial Stage (1960-1990), (ii). Growing Stage (1991-2009) and (iii). Stable Stage (2010-2019). The studies were conducted by 9,956 authors at 2,166 institutions across 100 countries. The United States, China, and Japan have the highest number of publications. The top three institutions with the highest number of publications are the Chinese Academy of Sciences, Kagawa University and USDA, USA. The top three authors are H. Kato-Noguchi, F.A. Macias, and C.H. Kong. The major Journals in this field are: (i). Allelopathy Journal, (ii). Journal of Chemical Ecology and (iii). Plant and Soil. The results of keyword clustering showed that the main research directions in this field are: (i). Metabonomics undergoing allelopathy, (ii). Functions of allelopathy substances, (iii). Molecular biology, (iv). Allelopathy of aquatic plants, (v). Alien plants invasion and (vi). Application of plant allelopathy in agroforestry production. Plant allelopathy is a research field that aims to maintain stable development. Future studies should focus on strengthening the cooperation among international scholars in plant allelopathy research and improving the output in frontier and hotspot areas. [ABSTRACT FROM AUTHOR]

Notoginseng Radix et Rhizoma is the tuberous root and rhizome of Panax notoginseng (Burk) F.H. Chen, a perennial plant of Ginseng (family Araliaceae). Traditional Chinese Medicine (TCM) considers it has strong flavour and provides warmth in liver and stomach. It is highly effective medicine to treat blood stasis, haemorrhage and pain. Many scholars have conducted research on the Panax notoginseng allelopathy. This review attempts to provide insight into the records of Sanchi in TCM, verify its name, efficacy of its producing areas and information about its cultivation and medicinal development. [ABSTRACT FROM AUTHOR]

We studied the allelopathic stress of C. ambrosioides volatile oil using the epidermal strip bioassay, microscopy and histochemical techniques on stomatal movement in leaves from broad beans (Vicia faba L.), peanuts (Arachis hypogaea L.) and peas (Pisum sativum L.). We also studied the changes in vacuoles, microfilaments and signalling molecules ROS, NO and Ca2+ in guard cells. The stomatal aperture of 3-test legume species decreased significantly (P < 0.05) in volatile oil concentration-dependent manner. Compared with control, the applied volatile oil increased the numbers of vacuoles but decreased their volume in guard cells of all 3-test crops. Aggregation of microfilament skeletons, increased the in ROS, NO and Ca2+ concentrations. These effects could be alleviated, when related inhibitors (Cytochalasin B, AS, LaCl3 and L-NAME) were used with volatile oil. It is speculated that the dynamic changes in guard cell microfilaments caused by volatile oil of C. ambrosioides could lead to increased ROS and NO levels by activating the related enzymes, which increased the cytoplasmic free Ca2+ levels in guard cells. Thereby the ion channels in plasma membrane and vacuolar membrane were affected. The bigger vacuoles in guard cells were divided into smaller ones, turgor pressure was decreased and stomata were closed. The stomatal movement of broad bean was most sensitive to volatile oil of C. ambrosioides, which showed strong allelopathy. [ABSTRACT FROM AUTHOR]