JOURNAL OF WEED SCIENCE RESEARCH最新文献

{"title":"WEED COMMUNITY ANALYSIS IN MAIZE CROP IN NATURAL CLIMATE OF KHAIRPUR DISTRICT, PAKISTAN","authors":"N. K. Khaskheli, M. H. Sirohi, A. R. Mahar, A. A. Mirbahar, M. A. Saand, Mirza Hussain","doi":"10.28941/pjwsr.v27i1.874","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.874","url":null,"abstract":"Weeds are the noxious plants that stunt growth and yield of many crops. This study recorded the community composition of weeds in maize crops grown at District Khairpur, Sindh Pakistan. The weeds were collected from the maize crops at three different localities using the quadrat method (60 quadrats/site). The species were identified and herbarium samples were preserved in Herbarium, Shah Abdul Latif University, Khairpur, Sindh Pakistan, for future reference. The species community composition, habit, and life span were determined. The study confirmed 35 weed species belonging to 14 plant families. The weed community was dominated by the plant families Poaceae (8 spp.), Amaranthaceae (7 spp.), and Aizoaceae (3 spp.). The most frequent species with relatively higher densities include Digera muricata (Amaranthaceae), Trianthema portulacastrum (Aizoaceae), and Corchorus olitorius (Malvaceae). The weed community was dominated with annual herbs. The community composition among the study sites was highly comparable. The study found a lack of weed management practices across the sites.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88678538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maize MAIZE YIELD AS AFFECTED BY METHODS OF TILLAGE AND WEED MANAGEMEMNT","authors":"Haseeb Ahmad, M. Shafi, Waqas Liaqat, Mehmood Jan, Shahzad Ahmad, M. Farooq","doi":"10.28941/pjwsr.v27i1.892","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.892","url":null,"abstract":"An experiment entitled: Maize yield as affected by methods of tillage and weed control methods was conducted at Agronomy Research Farms, The University of Agriculture Peshawar during summer 2016. The study was conducted in randomized complete block design (RCBD) with split plot arrangement having four replications. Tillage practices 1) Chisel plough + rotavator 2) Mouldboard plough + rotavator 3) Cultivator + rotavator and 4) Rotavator were assigned to main plots. Weed management practices included 1) Control, 2) Hoeing 15 days after sowing 3) Hoeing 15 and 30 days after sowing 4) Hoeing 15, 30 and 45 days after sowing, and 4) Herbicide (nicosulfuron) were kept into the subplots. The results revealed that chisel plough + rotavator has significantly reduced weeds m-2 (122, 101 and 125 weeds m-2), weeds fresh weight (19.73 g m-2, 116.35 g m-2 and 252.56 g m-2) and weeds dry weight (6.83 g m-2, 38.69 g m-2 and 80.61 g m-2) at 30, 45 and 60 days after sowing, respectively. The operation of chisel plough + rotavator has produced tallest plants (221.22 cm) with maximum grain rows ear-1 (16), grain yield (3586 kg ha-1) and shelling percentage (78.14%). Among weed control methods, hoeing 15, 30 and 45 days after sowing revealed maximum plant height (226.41 cm), grain rows ear-1 (16), grain yield (3604 kg ha-1) and shelling percentage (79.11%). All weed control methods have showed significant reduction in weeds m-2, weeds fresh weight and weeds dry weight. Interaction was also found significant for weeds m-2 at 60 DAS and grain yield of maize. Lowest weeds (56 weeds m-2) at 60 DAS and highest grain yield (4569 kg ha-1) was recorded when seedbed was prepared with chisel plough + rotavator with 3 hoeings (hoeing 15, 30 and 45 days after sowing). It is concluded that treatment of chisel plough + rotavator and hoeing 15, 30 and 45 days after sowing has significantly produced maximum grain yield of maize crop.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"91 11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77182545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing allelopathic potential of Sonchus oleraceus L. (milk thistle) on germination and seedling growth of Oryza puncta","authors":"B. Khan, S. Anwar, R. Maqbool, M. Amin, M. Javaid, Amjed Ali, Durrishahwar","doi":"10.28941/pjwsr.v27i1.864","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.864","url":null,"abstract":"ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that maximum mean emergence time (5.26 days) and minimum germination index (1.67), germination percentage (40%), seedling fresh weight (59 g) and dry weight (8 g) of O. punctata were examined with 8% aqueous extract of S. oleraceus fruit. However, 4% aqueous extract of S. oleraceus fruit produced minimum root length (5.71). On the basis this experiment it was concluded that 8% aqueous extract of S. oleraceus fruit can be used for controlling O. punctata weed. Keywords: Aqueous extract, environment, allelochamicals, hermetic response, stimulatory ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that maximum mean emergence time (5.26 days) and minimum germination index (1.67), germination percentage (40%), seedling fresh weight (59 g) and dry weight (8 g) of O. punctata were examined with 8% aqueous extract of S. oleraceus fruit. However, 4% aqueous extract of S. oleraceus fruit produced minimum root length (5.71). On the basis this experiment it was concluded that 8% aqueous extract of S. oleraceus fruit can be used for controlling O. punctata weed. Keywords: Aqueous extract, environment, allelochamicals, hermetic response, stimulatory ABSTRACT Aqueous extracts of plants are used to control weeds and having no hazards to environment and are inexpensive. Present study was undertaken to investigate the effect of aqueous extracts of Sonchus oleraceus L. on the Oryza punctata L. emergence and initial seedling growth. It consists of aqueous extract of leaves, stem and fruit of S. oleraceus at varying concentrations 0.25, 0.50, 1, 2, 4 and 8 % (w/v) along with a distilled water control. The allelochemicals present in the aqueous extracts showed stimulatory, inhibitory and hormetic responses depending upon the concentration and the plant part. Results directed that m","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"107 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91296955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation of leaf and root extracts from Allium sativum and Mentha piperita plants; evaluation of their antioxidant and anti-tyrosinase activities in-vitro","authors":"M. Rafiq, Farrukh Avais, Anser Ali, H. Javed, M. Saleem, Tehreem Tahir","doi":"10.28941/pjwsr.v27i1.869","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.869","url":null,"abstract":"Abstract-Tyrosinase is a key enzyme of melanogenesis which determines the mammalian skin, hair and eye colour. Hyper-pigmentation leads to various skin disorders like melasma, sunspots, age spots and freckles. Moreover, abnormal skin pigmentation is a serious aesthetic concern which leads to psychosocial problems. Thus to achieve melanin inhibition, inhibition of tyrosinase might be an effective approach. To this end we prepared methanolic (MeOH) extracts from leaves and roots of Allium sativum (AS) and Mentha piperita (MP), which were further processed for 1:1 fractional distillation to prepare methanolic n-hexane (MeOH_n-Hx), methanolic ethyl acetate (MeOH_EA) and methanolic chloroform (MeOH_CHCl3) extracts, aiming to evaluate tyrosinase and anti-oxidant activities in-vitro. Our results confirmed that all MeOH-crude AS and MP extracts showed significant anti-oxidant activity with IC50 values ranging from 0.05 ± 0.2 mg/ml to 4.3 ± 2.3mg/ml. Moreover, AS and MP all 16 extracts have significant anti-tyrosinase activity with IC50 range from 0.014 ± 0mg/ml to 1.205 ± 0.07mg/ml. Interestingly, AS leaf MetOH_EA, AS leaf MetOH_CHCl3, AS root MetOH_EA and MP leaf MetOH_CHCl3 showed significant anti-tyrosinase activity even higher than positive control kojic acid. AS leaf MetOH_CHCl3 extract being the most potent among all tested extracts is proposed as potential candidate to treat tyrosinase rooted hyper-pigmentation in future.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"76 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86634755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Long horned beetles ( Cerambycidae: Coleoptera) with new records from Pakistan","authors":"W. A. Panhwar, Kamran Ahmed Pathan, A. M. Shaikh, S. Ujjan, J. A. Ujan, K. Memon, Irfan Ahmed Pathan, Shabana Mangi","doi":"10.28941/pjwsr.v27i1.919","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.919","url":null,"abstract":"The longhorn beetles belongs to family Cerambycidae. The beetles are present in almost all ecosystems, except the ocean and Polar Regions. They are most the important biological control agents into agro-ecosystems. The beetles help in the biological control they eat extensive assortments of tree dwelling, soil dwelling insects and also eat caterpillars, maggots, aphids, bug, ants, wasp. Long horned beetles were gathered from different sites (agricultural fields and their surrounding vegetation) of district Naushahro Feroze with insect net (7.79 cm in diameter and 49.9 cm in length) and hand picking. A of 234 specimens were captured from October 2018 to July 2019. The material was identified into 07 species out of 06 genera. Of which Batocera rubus (Linnaeus, 1758), New Record from Sindh, Batocera rufomaculata (Charles De Geer, 1775), New Record from Sindh, Apriona cinerea (Chevrolat, 1852), New Record from Sindh, Archopalus exoticus (Sharp, 1905), New Record from Pakistan Macrotoma crenata (Fabricius, 1801), New Record from Pakistan, Prionus corpulantus (Bates, 1878) New Record from Sindh, Dorysthenes hugelii (Redtenbacher, 1848), New Record from Pakistan. The highest ratio of specimens were recorded from Mehrabpur and lowest ratio of specimens were recorded from Moro.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"131 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77974589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"eng English","authors":"Imtiaz Khan","doi":"10.28941/pjwsr.v27i1.915","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.915","url":null,"abstract":"A field experiment was conducted at the new developmental farm, the University of Agriculture Peshawar during rabi season 2016-17. A wheat variety Ata Habib was selected to be investigated to check its performance by adopting methods of sowing and mixed tank herbicides application. The experiment was arranged in split plot with randomized complete block (RCB) design and 4 replications to reduce the error of the results. For practical adaptation of the experiment, the sowing methods were presented as the main plots, while tank mixed herbicides were kept in the sub-plots to get good prominent results for possible positive differences among the treatments. The sub-plot size measured as 1.5 X 3 m while row to row distance was kept 30 cm. Data were recorded on weed density m-2, fresh and dry weed biomass (kg) , plant height (cm), spike length (cm), leaf area (cm) , number of tillers (m-2) , Number of grains spike-1, 1000 grain weight (g), biological yield (kg ha-1), and grain yield (kg ha-1), Harvest index (%). These data parameters were formally observed with great care to avoid any repetition or error of the data. Few noxious weeds were observed and recorded in the field viz. Avena fatua, Anagallis arvensis, Euphorbia helioscopia, Phalaris minor, Poa annua, Medicago denticulata, Convolvulus arvensis, Coronopus didymus, Fumaria polymorpha, Melilotus parviflora, Chenopodium album and Rumex crispus. The obtained results indicated that sowing methods were statistically significant for plant height, grains spike-1, 1000-grain weight and biological yield that showed a clear effectiveness of the recorded data parameters. In addition to this, herbicides applications were also were also statistically significant for all the parameters except grains spike-1, while the interaction of sowing methods and herbicides application were also non-significant. In sowing methods, line sowing provided satisfactory results. As general understandings various weeds were managed significantly through tank mixed herbicide applications with a ratio of 60-72% for broad leaf and grassy weeds respectively. Consequently the instant results provided 54% increased yield compared to the untreated treatments. Hence it is concluded that , line sowing in combination with tank mixed herbicides are more suitable for management of weeds in the wheat field and increased yield in the agro climatic conditions of Peshawar-Pakistan.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88273184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ETHYL ACETATE EXTRACT OF Chenopodium murale ROOT, A SOURCE OF BIOACTIVE COMPOUNDS","authors":"A. Javaid, S. F. Naqvi, Iqra Khan","doi":"10.28941/pjwsr.v27i1.926","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.926","url":null,"abstract":"Chenopodium murale L. is a winter weed of Chenopodiaceae. In this study, bioactive compounds present in ethyl acetate fraction of root extract of C. murale were identified. The weed plants were collected from Jehlem, Pakistan. Its roots were dried, powdered and extracted in methanol. After evaporation of the solvent, the remaining extract was mixed in water and partitioned with n-hexane, chloroform and finally with ethyl acetate. The last fraction was analyzed through GC-MS that indicated the presence of 15 compounds. These included the three major compounds namely o-xylene (15.03%), cyclopentanol (13.42) and 2-hexanol (13.99%). The moderately and less abundant compounds were ethylbenzene (5.47); methyl acetate (6.00%); cholestrol (4.33%); 2-phenanthrenol (3.01%); cyclohexanone (5.32%); p-xylene (5.12%); furostan-3,26-diyl dibenzoate (3.29%); dihexyl phthalate (4.99%); tricosanoic acid (2.74%); dioctyl phthalate (4.99%), hexanal (3.05%) and ergostane (1.29%). Literature survey showed that 10 of the identified compounds exhibited various biological activities including antifungal, antibacterial, antioxidant, anticancer and antipsoriatic. Most of the compounds were antimicrobial in nature.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75102506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COMPARATIVE EFFICACY OF FOUR ORGANIC SOLVENT FRACTIONS OF LEAF EXTRACT OF HEMP AGAINST Aspergillus versicolor","authors":"I. H. Khan, A. Javaid, Nadeem Shad","doi":"10.28941/pjwsr.v27i1.927","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.927","url":null,"abstract":"The fungus Aspergillus versicolor is generally found on food products and produces sterigmatocystin, a carcinogenic and hepatotoxic mycotoxin. This study reports the usefulness of polar and non-polar fractions of methanolic extract of hemp (Cannabis sativa L.) leaves against this fungus. Dried leaves of hemp were soaked in methanol for two weeks. After filtration and evaporation, water was added to the residual and partitioned with n-hexane, chloroform, ethyl acetate and n-butanol. Different concentrations of each fraction were prepared which ranged from 1.562 to 200 mg mL-1. Antifungal activity was carried out in malt extract broth medium. In general, all the concentrations of the four organic solvent fractions significantly controlled the growth of A. versicolor. There was 71–82%, 59–82%, 65–80% and 69–82% decline in biomass of A. versicolor due to n-hexane, chloroform, ethyl acetate and n-butanol fractions, respectively. It is concluded that different fractions of leaf extract of C. sativa has remarkable potential in controlling growth of A. versicolor.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89974051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PROXIMATE, MACRO ELEMENTAL AND GC-MS ANALYSIS OF SORBARIA TOMENTOSA","authors":"Shabnam Javed, A. Shoaib, Z. Mehmood","doi":"10.28941/pjwsr.v27i1.930","DOIUrl":"https://doi.org/10.28941/pjwsr.v27i1.930","url":null,"abstract":"Sorbaria tomentosa (LindI.) of family Rosaceae, is a wild, medicinal, ornamental, large, woody plant locally known as “Karhee or Berre”, native to Pakistan. Proximate composition gives important information to assess the suitability of medicinal flora or their extracts taken orally by the trivial communities. In the current study, different proximate parameters like carbohydrate, ash, protein, moisture content and fat, along with carbon, hydrogen, nitrogen and sulphur were analyzed in whole plant of S. tomentosa. The results revealed the occurrence of considerable proportion of carbohydrates (52%) and protein (23.80%). Moisture, fat and ash contents were found in small content 6.25, 2.02 and 0.20%, respectively. Elemental analysis displayed the greater content of carbon (44.92%) followed by content of hydrogen (6.16%), nitrogen (5.17%) and sulphur (0.43%). GC-MS analysis of n-hexane fraction of S. tomentosa led to identification of five compounds viz., 3, 13-Dimethylpentadecanoic acid (1), 2, 4-Dimethyltetradecanoic acid (2), 2, 4-Heptadecadienoic acid; Etester (3), 2-Butylcyclopropanedodecanoic acid (4) and Heptadecanoic acid; Et ester (5). Toxicity tests, further isolation and identification of active constituents of test weed could confirm the discovery of novel plant drugs and safety in administration.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82008879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A, The ESTIMATION OF ECONOMIC THRESHOLDS OF JUNGLE RICE (ECHINOCHLOA COLONA L.) AND FALSE AMARANTH (DIGERA ARVENSIS FORSSK.) IN DIRECT SEEDED RICE","authors":"Amir Ehsan, M. Safdar, Amjed Ali","doi":"10.28941/pjwsr.v26i4.890","DOIUrl":"https://doi.org/10.28941/pjwsr.v26i4.890","url":null,"abstract":"ABSTRACT There is little understanding about ecological interference of weeds in direct-seeded rice. To get estimates of economic thresholds of two weeds in direct seeded rice, two-year field trials were conducted at research area of College of Agriculture, University of Sargodha, Punjab-Pakistan. Treatments included 0, 22, 44, 66 and 88 plants m-2 densities of each of Echinochloa colona and Digera arvensis laid out in randomized complete block design. Augmented densities of E. colona (0, 22, 44, 66 and 88 weed plants m-2) enhanced its plant dry biomass up to 348 and 353%; and relative competitive index maximally to 80 and 77% in years 2015 and 2016, respectively. While the corresponding increases in plant dry weight and relative competitive index of D. arvensis were 367 and 360% and 79 and 82%. The enhancement in N (up to 258 & 257 %), P (up to 220 & 232%) and K (up to 293 & 301%) uptake in years 2015 and 2016, respectively were made by E. Colona whereas the corresponding increases in N, P and K assimilation by D. arvensis were as far as 265 & 257%, 238 & 233% and 305 & 298%, respectively. The declines in growth and yield of rice were observed in response to growing number of both the weeds. Rice grain yield losses ranged between 9.8 to 80% and 28 to 80% by E. Colona and D. arvensis. The economic thresholds of false amaranth and jungle rice were estimated to be 1.6-1.4 plants m-2 and 2.2-2.6 plants m-2, respectively.","PeriodicalId":17469,"journal":{"name":"JOURNAL OF WEED SCIENCE RESEARCH","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91087776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}