oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Allelopathic Potential of Wheat on Sourgrass Resistant to Glyphosate  [PDF]
Marcio Akira Ito, Germani Concen?o, Rodolpho Freire Marques, Sabrina Alves dos Santos, Maxwell Eliezer dos Santos Alves, Waggner Gomes Palharini, Thais Stradioto Melo, Laryssa Barbosa Xavier Silva, Larissa Tagara Linhares, Samara Emerim Concen?o
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.67097
Abstract: We aimed with this study to assay the allelopathic potential of wheat genotypes in inhibiting germination and initial growth of sourgrass (Digitaria insularis) resistant to the herbicide glyphosate. Two experiments were installed under greenhouse conditions: the first one aimed to assay the potential of wheat genotypes in inhibiting emergence and initial growth of two test plants, and the second aimed to evaluate the potential of those wheat genotypes which performed better at the first experiment, inhibiting the emergence and initial growth of sourgrass biotypes resistant to the herbicide glyphosate. Five doses of aqueous cool-extracted extract from 32 wheat genotypes were applied to tomato and cucumber (Experiment 1) aiming to identify the ones with higher inhibitory effect. The five most inhibitory wheat genotypes were selected for Experiment 2, where the same doses of extract were applied on sourgrass. For both experiments, shoot fresh and dry mass, as well as water content, were assessed. Sourgrass germination is affected by wheat extracts, but initial seedling growth seems not to be affected; wheat genotypes differ in terms of their allelopathic potential in inhibiting sourgrass germination; wheat presents little inhibitory effect on sourgrass.
The Allelopathic Potential of Hairy Vetch (Vicia villosa Roth.) Mulch  [PDF]
Charles M. Geddes, Andrea Cavalieri, Fouad Daayf, Robert H. Gulden
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.616267
Abstract: Hairy vetch (Vicia villosa Roth.) has been recognized as a good candidate for weed suppressive mulch in organic no-till cropping systems. In our study, the allelopathic potential of hairy vetch, fall rye (Secale cereale L.) and winter wheat (Triticum aestivum L.) (extracted species) were evaluated at both vegetative and reproductive developmental stages (extract stage) based on the germination and radicle elongation of five response species using aqueous extracts in soil microcosms. Our study found hairy vetch shoot extract to have little allelopathic potential compared to fall rye or winter wheat, both species for which the allelopathic potential is well documented. Interestingly, hairy vetch was the only extracted species to increase in allelopathic suppression of radicle elongation at the reproductive stage when plant biomass is near maximum. This result was conceivably due to the increased concentration of the putative allelochemical cyanamide in reproductive tissue. Chemical inhibition of radicle elongation in this extract, however, was only observed in the domesticated response species wheat (Triticum aestivum L.) and canola (Brassica napus L.). The allelopathic effect on germination varied and depended on extracted species, extract stage, and response species; whereas the effect on radicle elongation was similar among extracted species, yet unique within response species. This research demonstrated that allelopathy studies should include multiple allelopathic and response species to accurately quantify the magnitude of chemical effects among allelopathic species and to rule out potential phytotoxic chemical defense/detoxification mechanisms that exist in some response species.
Advances of research on allelopathic potential in compositae
菊科植物化感作用研究进展

ZHOU Kai,
周凯

生态学报 , 2004,
Abstract: Recent advances on allelopathic potential of different genera and species belonging to Compositae family were reviewed. Allelopathic potential had been confirmed in more than 39 genera and many different species of Compositae, especially in Solidago, Helianthus, Ageratum, Parthenium, Artemisia. The allelochemicals identified from different parts of Compositae plant included mainly terpenoids, polyacetylenes, phenolics, organic acids, which inhibited or stimulated the growth of certain treated plants. Their possible mechanisms of the action were discussed, including damage to cell membrane stability and disturbance of plant-water relationships in hibition of the oxidative phosphorylation, promotion or retardarce of chlorophyll synthesis, influence upon absorbance and utilization of mineral elements. Prospects the using some allelochemicals as plant growth regulators, natural herbicides, pesticides or leads for a synthetic herbicides and pesticides were discussed. It was expected the allelopathic potential of Compositae families might play an important role in the biocontrol of the overspread of exotic weed and maintenance of ecosystem balances. Based on current progress, allelopathic research trends in Compositae plant in the future would focused as following (1) approach of biochemistry synthesize pathways and the key enzymes of allelochemicals; (2) investigation and evaluation of compositae germplasm of allelopathic potential; (3) evolvement of allelopathy in natural ecosystem; (4) biochemistry mechanisms of autotoxicity and the strategies to overcome in some important species; (5) gene clone encoding the key enzymes of allelochemicals, further transgenes and the study of the gene expression in target species; and (6) research and application for allelopathy in sustainable developmental agriculture, especially as natural herbicide and pesticide models.
Research advances in wheat ( Triticum aestivum ) allelopathy
小麦化感作用研究进展

ZHANG Xiaoke,JIANG Yong,LIANG Wenju,KONG Chuihua,
张晓珂
,姜勇,梁文举,孔垂华

应用生态学报 , 2004,
Abstract: Wheat (Triticum aestivum ) is the main food crop in the world,and plays an important role in agricultural production.In order to enhance wheat yield,herbicides and germicides were intensively applied and made negative effects on the environment.Wheat possesses allelopathic potential for weed suppression and disease control through the release of secondary metabolites from its living plants or residues,which could avoid the environment pollution brought by herbicides and germicides.This paper reviewed the research advances in wheat allelopathy.Hydroxamic acids and phenolic acids are the predominant allelochemicals frequently reported which could produce plant natural defense against weed,pest and disease.The allelopathic activity of allelochemicals is determined not only by the allelochemicals,but also by the factors of inheritance,environment and biology.The retention,transportation and transformation processes of allelochemicals,and the relationship between wheat allelopathy and soil biota and its mechanism were seldom studied and still needed to be researched profoundly.Utilizing wheat allelopathy in plant protection,environment protection and crop breeding would improve the stress-resistance,yield and quality of wheat in agricultural production.
Fluorescence kinetics of different ecotypes of allelopathic wheat varieties at heading stage
不同生态型化感冬小麦抽穗期的荧光动力学特性

ZUO Sheng-Peng,YE Liang-Tao,MA Yong-Qing,
左胜鹏
,叶良涛,马永清

中国生态农业学报 , 2011,
Abstract: The agronomic traits of four ecotypes of allelopathic winter wheat varieties bred in different years were analyzed,and based on which fluorescence kinetics characteristics at heading stage were investigated via fluorescence quench technology.Potato was used as receptor to measure the allelopathic indices of the wheat varieties,and then the relationship of allelopathic potential with agronomic traits and chlorophyll fluorescence kinetics parameters analyzed.With the exception of Ningdong No.1,the agronomic t...
Allelopathic potential of sunflower (Helianthus annus L.) on soil metals and its leaves extracts on physiology of wheat (Triticum aestivum L.) seedlings.
J Kamal, A Bano
African Journal of Biotechnology , 2008,
Abstract: The effect of a sunflower (Helianthus annuus L.) variety, namely Hysun 38, on metals and of aqueous extracts of its leaves on germination in two varieties of wheat, namely Margalla 99 and Chakwall 97, were studied under laboratory conditions. In particular, the effect of leaf extract on hormones produced by wheat seedlings and on electrical conductivity, pH, Mn, Ca, K, P, and soil moisture content was examined. The leaf extract significantly inhibited the rate of germination and growth of seedlings.
POTENCIAL ALELOPáTICO DIFERENCIAL DE CULTIVARES DE TRIGO (TRITICUM AESTIVUM L.) CHILENO SOBRE BALLICA ANUAL (LOLIUM RIGIDUM) VAR. WIMMERA THE DIFFERENTIAL ALLELOPATHIC POTENTIAL OF CHILEAN WHEAT CULTIVARS (TRITICUM AESTIVUM L.) ON ANNUAL RYEGRASS (LOLIUM RIGIDUM) VAR. WIMMERA
Emma Bensch T,Heidi Schalchli S,Ricardo Fuentes P,Peter Seemann F
IDESIA , 2007,
Abstract: Los objetivos de esta investigación fueron: validar el método ECAM (Wu et al., 2000a) y determinar el potencial alelopático de cincuenta cvs. de trigo cultivados en Chile sobre ballica anual (Lolium rigidum) var. Wimmera. El dise o experimental fue completamente al azar y en bloque con cuatro repeticiones. Se evaluó largo radical mayor de la especie receptora (ballica) a los diez días de establecida. Los datos transformados a porcentaje de inhibición del largo radical de la especie receptora en relación al testigo fueron sometidos a ANDEVA, Análisis Cluster y Duncan o Tukey (P=0.05). El método ECAM modificado fue eficaz para evaluar el potencial alelopático de los cincuenta cultivares de trigo y, en general, se produjo inhibición del crecimiento radical de ballica con un rango de inhibición de 20 a 80%. Los cultivares más alelopáticos fueron Tukan, Oracle y Casta o y los con menor potencial Baroudeur, Paillaco y Domo. The objectives of this investigation were: to validate the ECAM method and to validate the allelopatic potential of 50 wheat cultivars on Lolium rigidum var. Wimmera. The experimental design was completely at random or in blocks with four repetitions. The longest main root of the receptive species (lolium grass) was evaluated ten days after the establishment of the last one. The transformed data into percentage of inhibition of root length of the receptive species in relation to the control was analized using ANDEVA, cluster analysis, Duncan or Tukey (P=0.05). The modified ECAM method was efficient to evaluate the allelopathic potential of fifty wheat cultivars. In most cases root development of Lolium rigidum var. Wimmera was inhibited, the range of inhibition varied for lolium grass beteween 20 to 80%. The most allelopathic cultivars were Tukan, Oracle and Casta o and with less potential Baroudeur, Paillaco and Domo.
Antifungal activity of wheat root exudate extracts on Gaeumannomyces graminis var. Tritici growth
Schalchli,H; Pardo,F; Hormazábal,E; Palma,R; Guerrero,J; Bensch,E;
Journal of soil science and plant nutrition , 2012, DOI: 10.4067/S0718-95162012000200012
Abstract: wheat (triticum aestivum l.) is known for its ability to produce and release al-lelopathic compounds, which have potential for controlling weeds and diseases. previous reports have shown the fungitoxic effects of allelochemicals present in wheat. thus, these compounds can be exuded by roots to protect the tissues directly affected by gaeumannomyces graminis var. tritici (ggt) fungus that causes wheat take-all disease. the aim of this research was to evaluate in vitro the allelopathic effect of root exudate extracts from four chilean wheat cultivars on ggt growth. root exudates were released from wheat seedlings to a sterile culture medium without nutrients. afterward, the exudates in the culture medium were separated by liquid-liquid extraction using ethyl acetate. eight different concentrations were tested for each cultivar. the results showed that the degree to which the extracts strongly inhibit the phytopathogen growth is highly dependent on both the concentration and the cultivar. the root extract of the domo cultivar was significantly active against ggt (mic=0.36 mg ml-1). ic50 and mic values obtained for dollinco and domo root exudate extracts showed toxicity to ggt. these findings may be considered in future studies related to the use of allelopathic potential as a selection factor in order to reduce the yield losses caused by various take-all diseases, as an alternative to chemical controls.
Antifungal activity of wheat root exudate extracts on Gaeumannomyces graminis var. Tritici growth  [cached]
H Schalchli,F Pardo,E Hormazábal,R Palma
Journal of Soil Science and Plant Nutrition , 2012,
Abstract: Wheat (Triticum aestivum L.) is known for its ability to produce and release al-lelopathic compounds, which have potential for controlling weeds and diseases. Previous reports have shown the fungitoxic effects of allelochemicals present in wheat. Thus, these compounds can be exuded by roots to protect the tissues directly affected by Gaeumannomyces graminis var. tritici (Ggt) fungus that causes wheat take-all disease. The aim of this research was to evaluate in vitro the allelopathic effect of root exudate extracts from four Chilean wheat cultivars on Ggt growth. Root exudates were released from wheat seedlings to a sterile culture medium without nutrients. Afterward, the exudates in the culture medium were separated by liquid-liquid extraction using ethyl acetate. Eight different concentrations were tested for each cultivar. The results showed that the degree to which the extracts strongly inhibit the phytopathogen growth is highly dependent on both the concentration and the cultivar. The root extract of the Domo cultivar was significantly active against Ggt (MIC=0.36 mg mL-1). IC50 and MIC values obtained for Dollinco and Domo root exudate extracts showed toxicity to Ggt. These findings may be considered in future studies related to the use of allelopathic potential as a selection factor in order to reduce the yield losses caused by various take-all diseases, as an alternative to chemical controls.
Allelopathic potential of Asarum europaeum toward Lycopersicon esculentum  [PDF]
Monica MARIAN,Anca PETER,Lucia MIHALESCU,Zorica VOSGAN
Analele Universitatii din Oradea, Fascicula Biologie , 2011,
Abstract: Asarum europaeum L. contains water-soluble substances which manifest allelopathic potential. Aqueous extracts from leaves and stems of Asarum europaeum were assayed to determine their allelopathic effects on Lycopersicon esculentum and Zea mays seeds germination and early seedling growth. The germination of the investigated seeds was found to be inhibited with increasing of the Asarum europaeum L. extract concentration. Moreover, the active substances extracted from leaves were found to be more inhibitory on the seeds germination in comparison with those extracted from stems.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.