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Min Tian - One of the best experts on this subject based on the ideXlab platform.
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How Does the Billy-Goat Produce Milk? Sergei Eisenstein’s Disintegration and Reconstitution of Kabuki Theatre
The Use of Asian Theatre for Modern Western Theatre, 2018Co-Authors: Min TianAbstract:Sergei Eisenstein’s interpretation of Kabuki theatre has gone fundamentally unquestioned and unchallenged for several decades. But what was exactly in Kabuki theatre—essentially the product of an alien and distant feudal society—that fed and stimulated the intellectual questions of Eisenstein, a twentieth-century Soviet avant-garde theatre and film director? How exactly did Eisenstein find in this centuries-old art form “an unexpected juncture” with the modernity of the sound film, or more precisely, his theory of montage? By a close examination of Eisenstein’s interpretation of Kabuki theatre, this chapter demonstrates that Eisenstein displaced and disintegrated the principles and techniques of Kabuki theatre from its historical and aesthetic contexts and appropriated and reconstituted them into his theoretical discourse. Thus, the “milk” Eisenstein extracted and reformulated from Kabuki theatre was no longer organically Japanese; it was artificially Eisensteinian, as the “Goat” had been “transgendered,” “genetically” altered, and historically and aesthetically displaced.
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how does the Billy Goat produce milk sergei eisenstein s disintegration and reconstitution of kabuki theatre
2018Co-Authors: Min TianAbstract:Sergei Eisenstein’s interpretation of Kabuki theatre has gone fundamentally unquestioned and unchallenged for several decades. But what was exactly in Kabuki theatre—essentially the product of an alien and distant feudal society—that fed and stimulated the intellectual questions of Eisenstein, a twentieth-century Soviet avant-garde theatre and film director? How exactly did Eisenstein find in this centuries-old art form “an unexpected juncture” with the modernity of the sound film, or more precisely, his theory of montage? By a close examination of Eisenstein’s interpretation of Kabuki theatre, this chapter demonstrates that Eisenstein displaced and disintegrated the principles and techniques of Kabuki theatre from its historical and aesthetic contexts and appropriated and reconstituted them into his theoretical discourse. Thus, the “milk” Eisenstein extracted and reformulated from Kabuki theatre was no longer organically Japanese; it was artificially Eisensteinian, as the “Goat” had been “transgendered,” “genetically” altered, and historically and aesthetically displaced.
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How Does the Billy-Goat Produce Milk? Sergei Eisenstein's Reconstitution of Kabuki Theatre
New Theatre Quarterly, 2016Co-Authors: Min TianAbstract:Through a close examination of Eisenstein's writings on the Kabuki theatre, Min Tian demonstrates in this article that Eisenstein's interpretation of Kabuki from the perspective of his theory displaced the techniques and principles of Kabuki theatre from its historical and aesthetic contexts. Predicated upon his ‘montage thinking’, Eisenstein reconstituted the techniques and principles integral to Kabuki as an organic whole in the context of his evolving and synthesizing theory. Min Tian has a PhD in theatre history from the University of Illinois at Urbana-Champaign and a doctorate at the Central Academy of Drama in Beijing. Currently teaching at the University of Iowa, he is the author of Mei Lanfang and the Twentieth-Century International Stage (2012) and The Poetics of Difference and Displacement: Twentieth-Century Chinese–Western Intercultural Theatre (2008), and editor of China's Greatest Operatic Male Actor of Female Roles: Documenting the Life and Art of Mei Lanfang, 1894–1961 (2010).
Ravinder Kumar Kohli - One of the best experts on this subject based on the ideXlab platform.
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Role of root-mediated interactions in phytotoxic interference of Ageratum conyzoides with rice (Oryza sativa).
Flora - Morphology Distribution Functional Ecology of Plants, 2009Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:Abstract Ageratum conyzoides L. (Billy Goat weed; Asteraceae) is an annual invasive weed native of tropical America and has now naturalized worldwide, particularly in Southeast Asia. The present study investigated the nature and potential of root-mediated allelopathic interference of A. conyzoides against rice ( Oryza sativa ). Root and shoot length and biomass accumulation of rice were significantly reduced (by 18–30%) when grown in the rhizosphere soil of the weed indicating the release of putative allelochemicals from the weed into the soil. The growth of rice was also progressively reduced in the soil amended with increasing amounts of root residues (5, 10 and 20 g kg −1 soil) of A. conyzoides . The addition of activated charcoal, an inert material with high affinity for organic biomolecules, partly ameliorated the negative effects of root residues amended in the soil. Further, there was no negative effect on the availability of soil nutrients in the root-amended soils. These were rather nutrient rich with greater electrical conductivity, and higher amount of organic matter, thus indicating no role in observed growth reduction. The reduction in allelopathic effects of root residue upon charcoal addition further indicated that putative phytotoxins released from the weed roots are water-soluble phenolic compounds. A significant amount of water-soluble phenolics were present in rhizosphere (∼6-times higher) and root-amended soils (∼5–10-fold higher) and their content was reduced (to ∼3.6–7.0-fold higher) when charcoal was added. The observed growth reduction in Ageratum rhizospheric or root-amended soils was concomitant with the amount of phenolic compounds. Upon HPLC analyses, these were identified as p- coumaric acid, gallic acid, ferulic acid, p- hydroxybenzoic acid and anisic acid. Under laboratory conditions, these phenolic acids reduced the root length and seedling weight of rice individually as well as in equimolar mixture, though no synergistic effect was noticed. The study concludes that root exudates and residues of A. conyzoides suppress the growth of rice by releasing phenolic allelochemicals into the soil rhizosphere and not through alteration of soil nutrients, and allelopathy plays a significant role in root-mediated negative interference of A. conyzoides .
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Nature of interference potential of leaf debris of Ageratum conyzoides
Plant Growth Regulation, 2008Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:The present study investigated the allelopathic interference of leaf debris of Ageratum conyzoides (Billy Goat weed; Asteraceae)—a weed of cultivated land—against rice ( Oryza sativa ). Seedling length and dry weight of rice were significantly reduced (16–20%) in soil from A. conyzoides infested fields compared to the soil from an area devoid of the weed. It indicated the presence of certain phytotoxins in the A. conyzoides infested soil. To explore the possible contribution of the weed in releasing these phytotoxins, growth studies involving leaf debris extracts and amended soils (prepared by incorporating leaf debris—5, 10, 20 g kg^−1 soil, w/w, or its extracts—0.5%, 1.0% and 2.0%, v/v) were conducted. The growth of rice was severely inhibited in A. conyzoides leaf debris- and debris extract-amended soils compared to unamended control soil. A significant amount of water-soluble phenolics, the potent phytotoxins, was found in the A. conyzoides infested soil, leaf debris, and debris-amended soils. These phenolics were identified as gallic acid, coumalic acid, protocatechuic acid, catechin and p- hydroxybenzoic acid. Among these, protocatechuic acid was in the maximum amount (35.72%) followed by coumalic acid (33.49%) and these two accounted for >69% of total phenolic compounds. Further, there was a significant increase in the available nutrient content in soil amended with A. conyzoides leaf debris thus ruling out the possibility of any resource depletion upon residue incorporation and their negative role in causing growth reduction. Based on the observations, the present study concludes that leaf debris of A. conyzoides deleteriously affects the early growth of rice by releasing water-soluble phenolic acids into the soil environment and not through soil nutrient depletion.
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Short communication Phytotoxicity of Ageratum conyzoides residues towards growth and nodulation of Cicer arietinum
2006Co-Authors: Daizy Rani Batish, Shalinder Kaur, Harminder Pal Singh, Ravinder Kumar KohliAbstract:AbstractA study was conducted to find out the phytotoxic effect of invasive weed Ageratum conyzoides on chickpea (Cicer arietinum). Weedresidues amended in the soil significantly reduced the chickpea growth. Root length, plant height and biomass of chickpea were lower in thesoilsamendedwithbelow-orabove-groundweedresidues.Inaddition,comparedtocontrol,thenodulation(nodulenumber,theirweightandleghemoglobin content) of chickpea was also reduced in the amended soils. The observed reduction in chickpea growth and nodulation wasattributed to the presence of phytotoxic phenolics in the residues.# 2005 Elsevier B.V. All rights reserved. Keywords: Residues; Phytotoxicity; Plant growth; Root nodules; Leghemoglobin content; Phenolics 1. IntroductionAgeratum conyzoides L. (Billy Goat weed; familyAsteraceae), a native of tropical America has now spreadtovarioustropicalandsubtropicalpartsoftheworldincludingIndia. It is an aromatic, annual weed of cultivated fields, butalso invades other ecosystems such as pastures, grasslands,wastelandsandevenforestareas.Intheagriculturalfields,itisvery troublesome, interferes with the growth and establish-ment of crops and reduces their yield (Bansal, 1988). Thesuccessful invasion of A. conyzoides is attributed to its widerange of environmental adaptability, higher reproductivepotentialandallelopathy.Asregardsitsallelopathicpotential,preliminary reports indicate that aqueous leaf, root andrhizospheresoilextractsinhibitthegrowthofotherplants(Jhaand Dhakal, 1990; Singh et al., 2003). Even, essential oilsextracted from the weed are inhibitory and suppress plantgrowth (Kong et al., 1999). In northwestern India, A.conyzoides is very common in thewheat and chickpea fieldsduringthewinterseasonandadverselyaffectsthecropgrowth(Bansal,1988).StudieshavedemonstratedthatA.conyzoidesaffects wheat growth by releasing water-soluble allelochem-icals into the immediate soil medium (Singh et al., 2003).However,nostudyhasbeendonetodetermineitsphytotoxiceffectonthegrowthofchickpea,whichisgenerallygrowninthe infested fields after manual removal of the weed. It ishypothesized that left over weed residues gradually mix intothe soil upon ploughing and/or decomposition, releasephytotoxicprinciplesandinterferewiththechickpeagrowth.To explore this, a study was therefore planned to assess theimpactofA.conyzoidesresiduesonthegrowthandnodulationof chickpea.2. Material and methodsResidues of A. conyzoides were collected from the weedinfested fields and brought to the laboratory. These wereshade dried, separated into above- and below-groundportions, powdered and filled into polyethylene bags.To study the phytotoxic impact of weed residues, soil was
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Impact of the invasive weed Ageratum conyzoides in the Shivalik Ranges of the north-western Himalayas, India.
2005Co-Authors: H. P. Singh, Ravinder Kumar Kohli, D. R. Batish, Vandana Arora, Shalinder Kaur, D. V. Alford, G. F. BackhausAbstract:In India, the north-western Himalayas are well-known for their rich floral diversity. However, during the last two decades a number of exotic weeds have invaded the area, thereby greatly threatening the natural vegetation (Kohli et al., 2005), causing irreversible damage to the structure and dynamics of natural communities. The allelopathic interference of these invading weeds also plays an important role in their invasiveness (Callaway & Aschehoug, 2003). Billy Goat weed (BGW) (Ageratum conyzoides) (Asteraceae) is an aromatic, invasive and exotic weed from tropical America that quickly encroaches upon any given area. BGW possesses a number of ecological strategies, such as fast growth rate, quick regenerative and reproductive potential, and greater tolerance/adaptability, helping it to form monocultural stands in the Shivalik Ranges of the north-western Himalayas. The weed has spread extensively in the Shivaliks, occupying various habitats (forests, plantations, agricultural fields, wastelands, grasslands) and now greatly affects the landscape (Kohli et al., 2004). However, a quantitative assessment of the native vegetation following BGW invasion in different habitats have not been done. A study was therefore conducted to assess the status of vegetation in various habitats (such as grasslands, a plantation, riparian regions and wastelands invaded by BGW in the Shivaliks. The studies were further extended to explore the effect of BGW residues on the growth of native species.
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Impact of Invasive Plants on the Structure and Composition of Natural Vegetation of Northwestern Indian Himalayas1
Weed Technology, 2004Co-Authors: Ravinder Kumar Kohli, Kuldip S. Dogra, Daizy R. Batish, Harminder Pal SinghAbstract:Abstract Himachal Pradesh situated in the lap of northwestern Himalayas is one of the richest repositories of plant diversity in India. However, during the past three decades, because of the increased pace of development and interference of humans through introduction of invasive exotics, the ecology of the state has changed tremendously. Ragweed parthenium, Billy Goat weed, and lantana—the three exotics from South America—have caused much harm in the state because of their invasive potential. A study conducted to assess the changes in the structural composition and dynamics of vegetation shows that density and diversity of native flora were adversely affected because of invasion by these three exotics. Because all the three exotic weeds are known to exhibit allelopathy, it might be one of the major nonresource–based hypothesis for the successful invasion by these exotic species. Nomenclature: Billy Goat weed, Ageratum conyzoides L.; lantana, Lantana camara L.; ragweed parthenium, Parthenium hysterophorus...
Daizy R. Batish - One of the best experts on this subject based on the ideXlab platform.
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Role of root-mediated interactions in phytotoxic interference of Ageratum conyzoides with rice (Oryza sativa).
Flora - Morphology Distribution Functional Ecology of Plants, 2009Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:Abstract Ageratum conyzoides L. (Billy Goat weed; Asteraceae) is an annual invasive weed native of tropical America and has now naturalized worldwide, particularly in Southeast Asia. The present study investigated the nature and potential of root-mediated allelopathic interference of A. conyzoides against rice ( Oryza sativa ). Root and shoot length and biomass accumulation of rice were significantly reduced (by 18–30%) when grown in the rhizosphere soil of the weed indicating the release of putative allelochemicals from the weed into the soil. The growth of rice was also progressively reduced in the soil amended with increasing amounts of root residues (5, 10 and 20 g kg −1 soil) of A. conyzoides . The addition of activated charcoal, an inert material with high affinity for organic biomolecules, partly ameliorated the negative effects of root residues amended in the soil. Further, there was no negative effect on the availability of soil nutrients in the root-amended soils. These were rather nutrient rich with greater electrical conductivity, and higher amount of organic matter, thus indicating no role in observed growth reduction. The reduction in allelopathic effects of root residue upon charcoal addition further indicated that putative phytotoxins released from the weed roots are water-soluble phenolic compounds. A significant amount of water-soluble phenolics were present in rhizosphere (∼6-times higher) and root-amended soils (∼5–10-fold higher) and their content was reduced (to ∼3.6–7.0-fold higher) when charcoal was added. The observed growth reduction in Ageratum rhizospheric or root-amended soils was concomitant with the amount of phenolic compounds. Upon HPLC analyses, these were identified as p- coumaric acid, gallic acid, ferulic acid, p- hydroxybenzoic acid and anisic acid. Under laboratory conditions, these phenolic acids reduced the root length and seedling weight of rice individually as well as in equimolar mixture, though no synergistic effect was noticed. The study concludes that root exudates and residues of A. conyzoides suppress the growth of rice by releasing phenolic allelochemicals into the soil rhizosphere and not through alteration of soil nutrients, and allelopathy plays a significant role in root-mediated negative interference of A. conyzoides .
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Nature of interference potential of leaf debris of Ageratum conyzoides
Plant Growth Regulation, 2008Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:The present study investigated the allelopathic interference of leaf debris of Ageratum conyzoides (Billy Goat weed; Asteraceae)—a weed of cultivated land—against rice ( Oryza sativa ). Seedling length and dry weight of rice were significantly reduced (16–20%) in soil from A. conyzoides infested fields compared to the soil from an area devoid of the weed. It indicated the presence of certain phytotoxins in the A. conyzoides infested soil. To explore the possible contribution of the weed in releasing these phytotoxins, growth studies involving leaf debris extracts and amended soils (prepared by incorporating leaf debris—5, 10, 20 g kg^−1 soil, w/w, or its extracts—0.5%, 1.0% and 2.0%, v/v) were conducted. The growth of rice was severely inhibited in A. conyzoides leaf debris- and debris extract-amended soils compared to unamended control soil. A significant amount of water-soluble phenolics, the potent phytotoxins, was found in the A. conyzoides infested soil, leaf debris, and debris-amended soils. These phenolics were identified as gallic acid, coumalic acid, protocatechuic acid, catechin and p- hydroxybenzoic acid. Among these, protocatechuic acid was in the maximum amount (35.72%) followed by coumalic acid (33.49%) and these two accounted for >69% of total phenolic compounds. Further, there was a significant increase in the available nutrient content in soil amended with A. conyzoides leaf debris thus ruling out the possibility of any resource depletion upon residue incorporation and their negative role in causing growth reduction. Based on the observations, the present study concludes that leaf debris of A. conyzoides deleteriously affects the early growth of rice by releasing water-soluble phenolic acids into the soil environment and not through soil nutrient depletion.
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Status, invasiveness and environmental threats of three tropical American invasive weeds (Parthenium hysterophorus L., Ageratum conyzoides L., Lantana camara L.) in India
Biological Invasions, 2006Co-Authors: Ravinder K. Kohli, H. P. Singh, Daizy R. Batish, Kuldip S. DograAbstract:Invasive weeds have threatened the integrity of ecosystems throughout the world. They affect not only the species diversity of native areas but also their biological integrity. In India, a number of invasive exotic weeds have been reported but some viz. Parthenium hysterophorus, Lantana camara and Ageratum conyzoides , especially those from tropical America are troublesome and have caused adverse ecological, economic and social impact. These weeds can be seen growing in different landscapes but are luxuriantly localized in unattended forests and cultivated areas. Parthenium hysterophorus (Asteraceae, commonly known as congress grass) is perhaps the most troublesome and noxious weed of urban and rural India. Besides rapidly colonizing areas replacing the native vegetation, it is also known to cause a number of human health problems such as skin allergy, rhinitis and irritation to eyes of the residents in the vicinity. Likewise, it causes fodder scarcity in addition to being unpalatable and toxic to livestock. Lantana camara (Verbenaceae), another serious tropical American pest, has encroached upon large areas of land, especially the forests where it has virtually replaced the forest floor vegetation and reduced tree growth. Also because of its bushy and spreading type of growth it obstructs forest operations. The third weed, Ageratum conyzoides (Asteraceae, Billy Goat weed) has invaded agricultural fields. It interferes with crops and causes yield reductions of major staple crops of India. When it invades rangeland areas, it out competes native grasses causing scarcity of fodder. These weeds have similar growth strategies such as fast growth rates, short life-cycles, greater reproductive potential, high competitive abilities and allelopathy that make them successful invaders of native habitats. Mechanical, chemical, biological and cultural control tactics have failed individually, though integrated approaches combining all these approaches along with community participation and proper land management have been relatively successful. This paper presents various aspects of biology, ecology, hazards and control measures of these weeds.
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Impact of Invasive Plants on the Structure and Composition of Natural Vegetation of Northwestern Indian Himalayas1
Weed Technology, 2004Co-Authors: Ravinder Kumar Kohli, Kuldip S. Dogra, Daizy R. Batish, Harminder Pal SinghAbstract:Abstract Himachal Pradesh situated in the lap of northwestern Himalayas is one of the richest repositories of plant diversity in India. However, during the past three decades, because of the increased pace of development and interference of humans through introduction of invasive exotics, the ecology of the state has changed tremendously. Ragweed parthenium, Billy Goat weed, and lantana—the three exotics from South America—have caused much harm in the state because of their invasive potential. A study conducted to assess the changes in the structural composition and dynamics of vegetation shows that density and diversity of native flora were adversely affected because of invasion by these three exotics. Because all the three exotic weeds are known to exhibit allelopathy, it might be one of the major nonresource–based hypothesis for the successful invasion by these exotic species. Nomenclature: Billy Goat weed, Ageratum conyzoides L.; lantana, Lantana camara L.; ragweed parthenium, Parthenium hysterophorus...
Harminder Pal Singh - One of the best experts on this subject based on the ideXlab platform.
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Role of root-mediated interactions in phytotoxic interference of Ageratum conyzoides with rice (Oryza sativa).
Flora - Morphology Distribution Functional Ecology of Plants, 2009Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:Abstract Ageratum conyzoides L. (Billy Goat weed; Asteraceae) is an annual invasive weed native of tropical America and has now naturalized worldwide, particularly in Southeast Asia. The present study investigated the nature and potential of root-mediated allelopathic interference of A. conyzoides against rice ( Oryza sativa ). Root and shoot length and biomass accumulation of rice were significantly reduced (by 18–30%) when grown in the rhizosphere soil of the weed indicating the release of putative allelochemicals from the weed into the soil. The growth of rice was also progressively reduced in the soil amended with increasing amounts of root residues (5, 10 and 20 g kg −1 soil) of A. conyzoides . The addition of activated charcoal, an inert material with high affinity for organic biomolecules, partly ameliorated the negative effects of root residues amended in the soil. Further, there was no negative effect on the availability of soil nutrients in the root-amended soils. These were rather nutrient rich with greater electrical conductivity, and higher amount of organic matter, thus indicating no role in observed growth reduction. The reduction in allelopathic effects of root residue upon charcoal addition further indicated that putative phytotoxins released from the weed roots are water-soluble phenolic compounds. A significant amount of water-soluble phenolics were present in rhizosphere (∼6-times higher) and root-amended soils (∼5–10-fold higher) and their content was reduced (to ∼3.6–7.0-fold higher) when charcoal was added. The observed growth reduction in Ageratum rhizospheric or root-amended soils was concomitant with the amount of phenolic compounds. Upon HPLC analyses, these were identified as p- coumaric acid, gallic acid, ferulic acid, p- hydroxybenzoic acid and anisic acid. Under laboratory conditions, these phenolic acids reduced the root length and seedling weight of rice individually as well as in equimolar mixture, though no synergistic effect was noticed. The study concludes that root exudates and residues of A. conyzoides suppress the growth of rice by releasing phenolic allelochemicals into the soil rhizosphere and not through alteration of soil nutrients, and allelopathy plays a significant role in root-mediated negative interference of A. conyzoides .
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Nature of interference potential of leaf debris of Ageratum conyzoides
Plant Growth Regulation, 2008Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:The present study investigated the allelopathic interference of leaf debris of Ageratum conyzoides (Billy Goat weed; Asteraceae)—a weed of cultivated land—against rice ( Oryza sativa ). Seedling length and dry weight of rice were significantly reduced (16–20%) in soil from A. conyzoides infested fields compared to the soil from an area devoid of the weed. It indicated the presence of certain phytotoxins in the A. conyzoides infested soil. To explore the possible contribution of the weed in releasing these phytotoxins, growth studies involving leaf debris extracts and amended soils (prepared by incorporating leaf debris—5, 10, 20 g kg^−1 soil, w/w, or its extracts—0.5%, 1.0% and 2.0%, v/v) were conducted. The growth of rice was severely inhibited in A. conyzoides leaf debris- and debris extract-amended soils compared to unamended control soil. A significant amount of water-soluble phenolics, the potent phytotoxins, was found in the A. conyzoides infested soil, leaf debris, and debris-amended soils. These phenolics were identified as gallic acid, coumalic acid, protocatechuic acid, catechin and p- hydroxybenzoic acid. Among these, protocatechuic acid was in the maximum amount (35.72%) followed by coumalic acid (33.49%) and these two accounted for >69% of total phenolic compounds. Further, there was a significant increase in the available nutrient content in soil amended with A. conyzoides leaf debris thus ruling out the possibility of any resource depletion upon residue incorporation and their negative role in causing growth reduction. Based on the observations, the present study concludes that leaf debris of A. conyzoides deleteriously affects the early growth of rice by releasing water-soluble phenolic acids into the soil environment and not through soil nutrient depletion.
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Short communication Phytotoxicity of Ageratum conyzoides residues towards growth and nodulation of Cicer arietinum
2006Co-Authors: Daizy Rani Batish, Shalinder Kaur, Harminder Pal Singh, Ravinder Kumar KohliAbstract:AbstractA study was conducted to find out the phytotoxic effect of invasive weed Ageratum conyzoides on chickpea (Cicer arietinum). Weedresidues amended in the soil significantly reduced the chickpea growth. Root length, plant height and biomass of chickpea were lower in thesoilsamendedwithbelow-orabove-groundweedresidues.Inaddition,comparedtocontrol,thenodulation(nodulenumber,theirweightandleghemoglobin content) of chickpea was also reduced in the amended soils. The observed reduction in chickpea growth and nodulation wasattributed to the presence of phytotoxic phenolics in the residues.# 2005 Elsevier B.V. All rights reserved. Keywords: Residues; Phytotoxicity; Plant growth; Root nodules; Leghemoglobin content; Phenolics 1. IntroductionAgeratum conyzoides L. (Billy Goat weed; familyAsteraceae), a native of tropical America has now spreadtovarioustropicalandsubtropicalpartsoftheworldincludingIndia. It is an aromatic, annual weed of cultivated fields, butalso invades other ecosystems such as pastures, grasslands,wastelandsandevenforestareas.Intheagriculturalfields,itisvery troublesome, interferes with the growth and establish-ment of crops and reduces their yield (Bansal, 1988). Thesuccessful invasion of A. conyzoides is attributed to its widerange of environmental adaptability, higher reproductivepotentialandallelopathy.Asregardsitsallelopathicpotential,preliminary reports indicate that aqueous leaf, root andrhizospheresoilextractsinhibitthegrowthofotherplants(Jhaand Dhakal, 1990; Singh et al., 2003). Even, essential oilsextracted from the weed are inhibitory and suppress plantgrowth (Kong et al., 1999). In northwestern India, A.conyzoides is very common in thewheat and chickpea fieldsduringthewinterseasonandadverselyaffectsthecropgrowth(Bansal,1988).StudieshavedemonstratedthatA.conyzoidesaffects wheat growth by releasing water-soluble allelochem-icals into the immediate soil medium (Singh et al., 2003).However,nostudyhasbeendonetodetermineitsphytotoxiceffectonthegrowthofchickpea,whichisgenerallygrowninthe infested fields after manual removal of the weed. It ishypothesized that left over weed residues gradually mix intothe soil upon ploughing and/or decomposition, releasephytotoxicprinciplesandinterferewiththechickpeagrowth.To explore this, a study was therefore planned to assess theimpactofA.conyzoidesresiduesonthegrowthandnodulationof chickpea.2. Material and methodsResidues of A. conyzoides were collected from the weedinfested fields and brought to the laboratory. These wereshade dried, separated into above- and below-groundportions, powdered and filled into polyethylene bags.To study the phytotoxic impact of weed residues, soil was
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Impact of Invasive Plants on the Structure and Composition of Natural Vegetation of Northwestern Indian Himalayas1
Weed Technology, 2004Co-Authors: Ravinder Kumar Kohli, Kuldip S. Dogra, Daizy R. Batish, Harminder Pal SinghAbstract:Abstract Himachal Pradesh situated in the lap of northwestern Himalayas is one of the richest repositories of plant diversity in India. However, during the past three decades, because of the increased pace of development and interference of humans through introduction of invasive exotics, the ecology of the state has changed tremendously. Ragweed parthenium, Billy Goat weed, and lantana—the three exotics from South America—have caused much harm in the state because of their invasive potential. A study conducted to assess the changes in the structural composition and dynamics of vegetation shows that density and diversity of native flora were adversely affected because of invasion by these three exotics. Because all the three exotic weeds are known to exhibit allelopathy, it might be one of the major nonresource–based hypothesis for the successful invasion by these exotic species. Nomenclature: Billy Goat weed, Ageratum conyzoides L.; lantana, Lantana camara L.; ragweed parthenium, Parthenium hysterophorus...
Shalinder Kaur - One of the best experts on this subject based on the ideXlab platform.
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Role of root-mediated interactions in phytotoxic interference of Ageratum conyzoides with rice (Oryza sativa).
Flora - Morphology Distribution Functional Ecology of Plants, 2009Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:Abstract Ageratum conyzoides L. (Billy Goat weed; Asteraceae) is an annual invasive weed native of tropical America and has now naturalized worldwide, particularly in Southeast Asia. The present study investigated the nature and potential of root-mediated allelopathic interference of A. conyzoides against rice ( Oryza sativa ). Root and shoot length and biomass accumulation of rice were significantly reduced (by 18–30%) when grown in the rhizosphere soil of the weed indicating the release of putative allelochemicals from the weed into the soil. The growth of rice was also progressively reduced in the soil amended with increasing amounts of root residues (5, 10 and 20 g kg −1 soil) of A. conyzoides . The addition of activated charcoal, an inert material with high affinity for organic biomolecules, partly ameliorated the negative effects of root residues amended in the soil. Further, there was no negative effect on the availability of soil nutrients in the root-amended soils. These were rather nutrient rich with greater electrical conductivity, and higher amount of organic matter, thus indicating no role in observed growth reduction. The reduction in allelopathic effects of root residue upon charcoal addition further indicated that putative phytotoxins released from the weed roots are water-soluble phenolic compounds. A significant amount of water-soluble phenolics were present in rhizosphere (∼6-times higher) and root-amended soils (∼5–10-fold higher) and their content was reduced (to ∼3.6–7.0-fold higher) when charcoal was added. The observed growth reduction in Ageratum rhizospheric or root-amended soils was concomitant with the amount of phenolic compounds. Upon HPLC analyses, these were identified as p- coumaric acid, gallic acid, ferulic acid, p- hydroxybenzoic acid and anisic acid. Under laboratory conditions, these phenolic acids reduced the root length and seedling weight of rice individually as well as in equimolar mixture, though no synergistic effect was noticed. The study concludes that root exudates and residues of A. conyzoides suppress the growth of rice by releasing phenolic allelochemicals into the soil rhizosphere and not through alteration of soil nutrients, and allelopathy plays a significant role in root-mediated negative interference of A. conyzoides .
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Nature of interference potential of leaf debris of Ageratum conyzoides
Plant Growth Regulation, 2008Co-Authors: Daizy R. Batish, Harminder Pal Singh, Shalinder Kaur, Ravinder Kumar KohliAbstract:The present study investigated the allelopathic interference of leaf debris of Ageratum conyzoides (Billy Goat weed; Asteraceae)—a weed of cultivated land—against rice ( Oryza sativa ). Seedling length and dry weight of rice were significantly reduced (16–20%) in soil from A. conyzoides infested fields compared to the soil from an area devoid of the weed. It indicated the presence of certain phytotoxins in the A. conyzoides infested soil. To explore the possible contribution of the weed in releasing these phytotoxins, growth studies involving leaf debris extracts and amended soils (prepared by incorporating leaf debris—5, 10, 20 g kg^−1 soil, w/w, or its extracts—0.5%, 1.0% and 2.0%, v/v) were conducted. The growth of rice was severely inhibited in A. conyzoides leaf debris- and debris extract-amended soils compared to unamended control soil. A significant amount of water-soluble phenolics, the potent phytotoxins, was found in the A. conyzoides infested soil, leaf debris, and debris-amended soils. These phenolics were identified as gallic acid, coumalic acid, protocatechuic acid, catechin and p- hydroxybenzoic acid. Among these, protocatechuic acid was in the maximum amount (35.72%) followed by coumalic acid (33.49%) and these two accounted for >69% of total phenolic compounds. Further, there was a significant increase in the available nutrient content in soil amended with A. conyzoides leaf debris thus ruling out the possibility of any resource depletion upon residue incorporation and their negative role in causing growth reduction. Based on the observations, the present study concludes that leaf debris of A. conyzoides deleteriously affects the early growth of rice by releasing water-soluble phenolic acids into the soil environment and not through soil nutrient depletion.
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Short communication Phytotoxicity of Ageratum conyzoides residues towards growth and nodulation of Cicer arietinum
2006Co-Authors: Daizy Rani Batish, Shalinder Kaur, Harminder Pal Singh, Ravinder Kumar KohliAbstract:AbstractA study was conducted to find out the phytotoxic effect of invasive weed Ageratum conyzoides on chickpea (Cicer arietinum). Weedresidues amended in the soil significantly reduced the chickpea growth. Root length, plant height and biomass of chickpea were lower in thesoilsamendedwithbelow-orabove-groundweedresidues.Inaddition,comparedtocontrol,thenodulation(nodulenumber,theirweightandleghemoglobin content) of chickpea was also reduced in the amended soils. The observed reduction in chickpea growth and nodulation wasattributed to the presence of phytotoxic phenolics in the residues.# 2005 Elsevier B.V. All rights reserved. Keywords: Residues; Phytotoxicity; Plant growth; Root nodules; Leghemoglobin content; Phenolics 1. IntroductionAgeratum conyzoides L. (Billy Goat weed; familyAsteraceae), a native of tropical America has now spreadtovarioustropicalandsubtropicalpartsoftheworldincludingIndia. It is an aromatic, annual weed of cultivated fields, butalso invades other ecosystems such as pastures, grasslands,wastelandsandevenforestareas.Intheagriculturalfields,itisvery troublesome, interferes with the growth and establish-ment of crops and reduces their yield (Bansal, 1988). Thesuccessful invasion of A. conyzoides is attributed to its widerange of environmental adaptability, higher reproductivepotentialandallelopathy.Asregardsitsallelopathicpotential,preliminary reports indicate that aqueous leaf, root andrhizospheresoilextractsinhibitthegrowthofotherplants(Jhaand Dhakal, 1990; Singh et al., 2003). Even, essential oilsextracted from the weed are inhibitory and suppress plantgrowth (Kong et al., 1999). In northwestern India, A.conyzoides is very common in thewheat and chickpea fieldsduringthewinterseasonandadverselyaffectsthecropgrowth(Bansal,1988).StudieshavedemonstratedthatA.conyzoidesaffects wheat growth by releasing water-soluble allelochem-icals into the immediate soil medium (Singh et al., 2003).However,nostudyhasbeendonetodetermineitsphytotoxiceffectonthegrowthofchickpea,whichisgenerallygrowninthe infested fields after manual removal of the weed. It ishypothesized that left over weed residues gradually mix intothe soil upon ploughing and/or decomposition, releasephytotoxicprinciplesandinterferewiththechickpeagrowth.To explore this, a study was therefore planned to assess theimpactofA.conyzoidesresiduesonthegrowthandnodulationof chickpea.2. Material and methodsResidues of A. conyzoides were collected from the weedinfested fields and brought to the laboratory. These wereshade dried, separated into above- and below-groundportions, powdered and filled into polyethylene bags.To study the phytotoxic impact of weed residues, soil was
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Impact of the invasive weed Ageratum conyzoides in the Shivalik Ranges of the north-western Himalayas, India.
2005Co-Authors: H. P. Singh, Ravinder Kumar Kohli, D. R. Batish, Vandana Arora, Shalinder Kaur, D. V. Alford, G. F. BackhausAbstract:In India, the north-western Himalayas are well-known for their rich floral diversity. However, during the last two decades a number of exotic weeds have invaded the area, thereby greatly threatening the natural vegetation (Kohli et al., 2005), causing irreversible damage to the structure and dynamics of natural communities. The allelopathic interference of these invading weeds also plays an important role in their invasiveness (Callaway & Aschehoug, 2003). Billy Goat weed (BGW) (Ageratum conyzoides) (Asteraceae) is an aromatic, invasive and exotic weed from tropical America that quickly encroaches upon any given area. BGW possesses a number of ecological strategies, such as fast growth rate, quick regenerative and reproductive potential, and greater tolerance/adaptability, helping it to form monocultural stands in the Shivalik Ranges of the north-western Himalayas. The weed has spread extensively in the Shivaliks, occupying various habitats (forests, plantations, agricultural fields, wastelands, grasslands) and now greatly affects the landscape (Kohli et al., 2004). However, a quantitative assessment of the native vegetation following BGW invasion in different habitats have not been done. A study was therefore conducted to assess the status of vegetation in various habitats (such as grasslands, a plantation, riparian regions and wastelands invaded by BGW in the Shivaliks. The studies were further extended to explore the effect of BGW residues on the growth of native species.