Seedling establishment early on an abandoned field

The effect of sporadic cultivation on seedling establishment on a field abandoned for 1–4 years was investigated in small-plot trials at Prague-Ruzyně in the spring periods 1993–1995. Cultivation included autumn ploughing, spring harrowing and rolling on all plots that were subsequently left to spontaneous weed infestation. Some plots were then mowed or shallowly cultivated in mid-June and late July, others were left without treatment. No significant differences in seedling establishment were found between plots with different treatments. The number of species varied between years, but without a trend to species enrichment or impoverishment. In all years most species were annuals, and species composition did not change in the course of the experiment. The dominant species were Amaranthus retroflexus, Lamium amplexicaule, Echinochloa crus-galli, Chenopodium album, Silene noctiflora and Thlaspi arvense. Species diversity during the experimental years increased due to decreasing dominance of A. retroflexus.

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Weed Species Composition of Agrophytocenoses in Altai Krai

Acta Biologica Sibirica ◽

10.3897/abs.7.e60884 ◽

2021 ◽

Vol 7 ◽

pp. 93-102

Author(s):

Tatiana A. Terekhina ◽

Alyona V. Nochevnaya ◽

Natalia V. Ovcharova ◽

Irina A. Lapshina

Keyword(s):

Species Composition ◽

Chenopodium Album ◽

Amaranthus Retroflexus ◽

Lower Percentage ◽

Weed Species ◽

Convolvulus Arvensis ◽

The Road ◽

Poaceae Family ◽

Weed Infestation ◽

Brassicaceae Family

The article reviews the weed species composition of oat, sunflower, wheat, buckwheat, rapeseed and flax agrophytocenoses on 390 fields in 21 districts of Altai Krai: Aleyskiy, Bistroistokskiy, Baevskiy, Burlinskiy, Kamenskiy, Kosikhinskiy, Krutikhinskiy, Kytmanovskiy, Loktevskiy, Mamontovskiy, Novichikhinskiy, Pankrushikhinskiy, Rebrikhinskiy, Rubtsovskiy, Shipunovskiy, Sovetskiy, Tretyakovskiy, Troitskiy, Tyumentsevskiy, Zarinskiy, and Zonalniy. The studied fields were surveyed by the route method, which involved the study of the plot by examining it along two diagonals and four sides, when the area did not exceed 20.0 hectares. Larger fields were divided into plots of 20.0 hectares before the survey. The areas adjacent to roads were examined most carefully, since it is often from the road that the field becomes infested. We used the ArcGis program to compile original maps for the main weed plant species. It was found that out of 45 species encountered, only 10 play a significant role in weed infestation and have a high frequency rate: aboriginal Convolvulus arvensis, Amaranthus retroflexus, Euphorbia virgata, Lathyrus tuberosus, Chenopodium album, as well as such adventive species as Fallopia convolvulus, Setaria pumila, Panicum miliaceum subsp. ruderale, Avena fatua and Echinochloa crusgalli. The largest number of species accounts for the Poaceae family (33.3%). The Brassicaceae family is characterized by a slightly lower percentage of participation in the adventitious flora (27.7%). Other families are not so well represented (by 1-2 species each).

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Efficacy and selectivity of post-emergent application of flumioxazin and oxyfluorfen in sunflower

Plant Soil and Environment ◽

10.17221/285/2011-pse ◽

2011 ◽

Vol 57 (No. 11) ◽

pp. 532-539 ◽

Cited By ~ 7

Author(s):

M. Jursík ◽

J. Andr ◽

J. Holec ◽

J. Soukup

Keyword(s):

Chenopodium Album ◽

Field Trials ◽

Amaranthus Retroflexus ◽

Alcohol Ethoxylate ◽

Thlaspi Arvense ◽

Full Control ◽

Application Rates ◽

Herbicide Treatments ◽

Small Plot ◽

Mercurialis Annua

Four efficacy and selectivity small plot field trials were carried out in four sunflower hybrids at two localities in Middle Bohemia during 2008 and 2009 with herbicides containing the active ingredients flumioxazin and fluorochloridone. For Chenopodium album, an efficacy of 97% was found after pre-emergent application of fluorochloridone + acetochlor; the efficacy of oxyfluorfen was 88–95%; the efficacy of flumioxazin was below 50% at both tested application rates (30 and 60 g/ha) and application timings (2 sunflower leaves and 4 to 6 sunflower leaves); efficacy of flumioxazin increased to 67% and 69%, when surfactants were added (isodecyl alcohol ethoxylate and heptamethyltrisiloxan). Full control of Amaranthus retroflexus was found after all pre-emergent and early post-emergent herbicide treatments; efficacy of late post-emergent herbicide treatments was below 93%. Full control of Mercurialis annua was found only after application of oxyfluorfen. Thlaspi arvense was fully controlled by fluorochloridone + acetochlor (pre-emergent) and oxyfluorfen (in both application terms). Selectivity of the four tested sunflower hybrids to fluorochloridone + acetochlor, bifenox and flumioxazin was acceptable (phytotoxicity 6 to 27%). Higher phytotoxicity (23–45%) was recorded when surfactants were added to flumioxazin. The highest phytotoxicity (68–81%) was recorded after the application of oxyfluorfen.  

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Composition and diversity of anurans in the Restinga of the Conde municipality, northern coast of the state of Bahia, northeastern Brazil

Biota Neotropica ◽

10.1590/1676-0611-bn-2016-0157 ◽

2016 ◽

Vol 16 (3) ◽

Cited By ~ 3

Author(s):

Felipe Augusto Trindade Gondim-Silva ◽

Alessandra Rodrigues Santos Andrade ◽

Rafael Oliveira Abreu ◽

Jamile Santos Nascimento ◽

Geovane Paixão Corrêa ◽

...

Keyword(s):

Species Richness ◽

Species Diversity ◽

Species Composition ◽

Rainy Season ◽

Dominant Species ◽

The State ◽

Northeastern Brazil ◽

Freshwater Wetland ◽

Northern Coast ◽

Anuran Species

Abstract The Conde municipality is located in the northern coast of the state of Bahia (NC), northeastern Brazil, and is part of the Atlantic Tropical domain. The anuran fauna of the northern portion of the NC is still poorly known if compared to the southern portion. The Restinga is one of the predominant environments of the coastal plains of the NC and it is characterized essentially by presenting sandy soil covered by herbaceous and shrubby vegetation. The objective of this study was to determine the anuran species composition and diversity for the Restinga of the Conde municipality. Sampling was carried out at night by active search over four periods of five consecutive days each, two over the 'main rainy season' and two in a 'lesser rainy season', using 14 sample units (SUs) and five extra sample plots (EPs). We calculated dominance and species diversity using the Berger-Parker and Shannon-Wiener H' indices, respectively. We used accumulation curves and the Jackknife 1 estimator to estimate anuran species richness, considering only the data obtained from the SUs. We recorded 713 anuran specimens distributed within 33 species, 13 genera and five families (Bufonidae, Craugastoridae, Hylidae, Leptodactylidae and Microhylidae). The Hylidae and Leptodactylidae families had the highest species richness. Considering only the SUs (Jackknife 1 estimator in brackets), we recorded 28 species in the study area (33.9 ± 2.3), 13 in Shrubby Vegetation Zones - SVZ (20.8 ± 2.9) and 25 in Freshwater Wetland Zones - FWZ (28.9 ± 1.9). The abundance and species diversity of the FWZ (n = 638 specimens; H'= 2.4) were higher than those recorded for the SVZ (n = 52 specimens; H' = 1.9). The SVZ and FWZ showed distinct dominant species, wherein Pristimantis paulodutrai was the dominant species in SVZ and Scinax fuscomarginatus in FWZ. The Restinga of the Conde municipality stands out as the one with the highest anuran species richness already recorded considering only SVZ and FWZ. Moreover, its anuran species composition represented 55% of the anuran species known for the NC and included taxa common to three different morphoclimatic domains (Tropical Atlantic, Cerrado and Caatinga).

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A COMPARISON OF MCP AND 2,4-D FOR THE CONTROL OF ANNUAL WEEDS IN GRAIN CROPS

Canadian Journal of Plant Science ◽

10.4141/cjps57-008 ◽

1957 ◽

Vol 37 (1) ◽

pp. 69-83 ◽

Cited By ~ 1

Author(s):

H. A. Friesen ◽

D. R. Walker

Keyword(s):

Chenopodium Album ◽

Amaranthus Retroflexus ◽

Seedling Stage ◽

Dichlorophenoxyacetic Acid ◽

Growth Stages ◽

Thlaspi Arvense ◽

Wild Mustard ◽

The Difference ◽

Lamb’S Quarters ◽

2,4 Dichlorophenoxyacetic Acid

Oats, flax and barley were sprayed with various formulations of MCP (2-methyl-4-chlorophenoxyacetic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid) at a number of Experimental Farms in Western Canada in 1954 and 1955. Each formulation was applied at 4 and 8 ounces of acid equivalent per acre at each of two dates, viz., Date 1, when the weeds were in the seedling stage less than 3 inches in height; and Date 2, at a stage coinciding with the first appearance of buds on the major weed species.Stinkweed (Thlaspi arvense, L.), wild mustard (Brassica kaber (DC.) L.C. Wheeler var. pinnatifida (Stokes) L.C. Wheeler), lamb's quarters (Chenopodium album L.), Russian pigweed (Axyris amarantoides L.), and ball mustard (Neslia paniculata L.), were effectively controlled by each of the MCP and 2,4-D formulations used. Russian thistle (Salsola kali L.), and red-root pigweed (Amaranthus retroflexus L.), were not satisfactorily controlled by MCP, whereas hemp nettle (Galeopsis tetrahit L.) was not controlled by 2,4-D. Wild buckwheat (Polygonum convolvulus L.) was not controlled by any of the treatments. Each treatment was more effective when applied during the seedling stage of the weeds.On the basis of wood control and yield of grain the results of this study favour the use of MCP over 2,4-D with either oats or flax. Oats was significantly more tolerant to MCP, particularly if treated during the early growth stages when weed competition was most critical. With flax, the difference in tolerance was most pronounced in favour of MCP at the later date of treatment. The 2,4-D ester and low volatile ester resulted in a preponderance of plant deformities, lowered the yields of both oats and flax and delayed the maturity of flax significantly. Barley yields in this study were not adversely affected by any of the treatments.

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AMINO ACID AND PROXIMATE ANALYSES OF WEED SEEDS

Canadian Journal of Plant Science ◽

10.4141/cjps77-033 ◽

1977 ◽

Vol 57 (1) ◽

pp. 243-249 ◽

Cited By ~ 13

Author(s):

RUSSELL TKACHUK ◽

V. JEAN MELLISH

Keyword(s):

Amino Acid ◽

Chenopodium Album ◽

Essential Amino Acids ◽

Amaranthus Retroflexus ◽

Thlaspi Arvense ◽

Wild Mustard ◽

Acid Protein ◽

Weed Seeds ◽

Lamb’S Quarters ◽

Amino Acid Balance

Weed seeds commonly found in Western Canadian cereals and oil seeds as dockage were examined for their amino acid, protein, oil and fiber contents. The weeds analyzed were Sinapis arvenis L.(wild mustard), Thlaspi arvense L. (stinkweed), Descurainia sophia (L.) Webb (flixweed), Polygonum convolvulus L. (wild buckwheat), Rumex pseudonatronatus L. (field dock), Avena fatua L. (wild oats), Setaria viridis (L.) Beauv. (green foxtail), Iva xanthifolia Nutt. (false ragweed), Chenopodium album L. (lamb’s-quarters), and Amaranthus retroflexus L. (redroot pigweed). Composite analysis showed that some of the weed seeds are high in protein and oil content. Amino acid analysis showed that many weeds have an excellent essential amino acid balance, and also a higher content of essential amino acids than do the commonly grown cereals. These results suggest that some weed seeds could be excellent sources of protein and oil for feed or food purposes.

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Changes in fish species diversity and dominant species composition in the Yellow Sea

Fisheries Research ◽

10.1016/0165-7836(95)00422-x ◽

1996 ◽

Vol 26 (3-4) ◽

pp. 337-352 ◽

Cited By ~ 59

Author(s):

Xianshi Jin ◽

Qisheng Tang

Keyword(s):

Species Diversity ◽

Species Composition ◽

Fish Species ◽

Yellow Sea ◽

Dominant Species ◽

The Yellow Sea ◽

Fish Species Diversity

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The competitive ability of Chenopodium album and Echinochloa crus-galli in maize crops depending on the time of their occurrence or removal

Acta Agrobotanica ◽

10.5586/aa.1688 ◽

2016 ◽

Vol 69 (4) ◽

Cited By ~ 2

Author(s):

Hanna Golebiowska ◽

Renata Kieloch

Keyword(s):

Competitive Ability ◽

Stem Elongation ◽

Chenopodium Album ◽

Weed Competition ◽

Growth Stages ◽

Competitive Effect ◽

Leaf Stage ◽

Weed Infestation ◽

Small Plot ◽

Weed Emergence

Small-plot experiments for two levels of infestation (20 and 40 plants per m2) with Chenopodium album L. and Echinochloa crus-galli (L.) P. Beav were conducted in the 2009–2011 seasons. In the first variant, the effect of time of weed removal on maize was investigated. Weeds were removed in the following growth stages of maize: one, three, five, and seven leaves, the beginning of stem elongation, and the stage from the fourth to sixth node. The second variant concerned the effect of time of weed emergence on maize and included the same maize growth stages as mentioned above. In both treatments, weed competition was compared to the control – the plot completely free from weeds, as well as to the plot fully covered with weeds. Echinochloa crus-galli in the amount of 20 plants per m2, which were not removed until the five-leaf stage or which emerged immediately after the seven-leaf stage of maize, did not show any competitive effect on the growth and development of maize. Chenopodium album was characterized by a similar effect at the same level of weed infestation severity and when not removed until the five-leaf stage as well as in the case of plants that emerged after the seven-leaf stage of maize. Both species present in an amount of 40 plants per m2 needed to be removed no later than at the three-leaf stage of maize.

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Tram tracks as specific anthropogenic habitats for the growth of plants

10.7287/peerj.preprints.2606 ◽

2016 ◽

Author(s):

Paulina Woźnica ◽

Alina Urbisz ◽

Andrzej Urbisz ◽

Izabella Franiel

Keyword(s):

Species Composition ◽

Dominant Species ◽

Nitrate Nitrogen ◽

Plantago Lanceolata ◽

Floristic Composition ◽

Amaranthus Retroflexus ◽

Achillea Millefolium ◽

Silene Vulgaris ◽

Anthropogenic Habitats ◽

Hieracium Pilosella

Although tramway tracks are found in most cities, their flora is not thoroughly researched. Many more studies relate to railway areas as specific anthropogenic habitats for the development of plants. Both railway and tram tracks represent specific ecological migration corridors for plants. The objective of this study was to determine the relationship between the floristic composition and selected soil parameters of tram tracks. In 2014-2015, floristic studies were carried out along tram tracks in the Upper Silesian conurbation (southern Poland). Depending on the dominant species, five groups of sites with varying floristic composition were distinguished. Five plots with an area of 1 m2 were randomly selected in each of the sites. The species composition was determined at each plot together with the cover-abundance of all species occurring at a given plot according to Westhoff’s and van Maarel’s scale. Soil samples were collected from each plot and analysed for pH, the content of biogenic elements and heavy metals. A total of 329 species of vascular plants were identified on the tram tracks of the surveyed area, and 40 species on the plots. The dominant species included: Amaranthus retroflexus, Achillea millefolium, Plantago lanceolata, Hieracium pilosella, Silene vulgaris, Taraxacum sp. and Trifolium repens. Grouping of plots in respect of soil factors largely reflects their species composition. It has been found that the content of nitrate nitrogen, lead and phosphorus has the strongest impact on the floristic diversity of the railway tracks. Based on these parameters, three groups of species were distinguished: nitrophytes, metallophytes and common, i.e. not closely associated with the studied soil properties. Three habitat types of varying plant species composition were distinguished based on the content of nitrate nitrogen and lead: 1) nitrophilous dominated by Amaranthus retroflexus, 2) with increased content of heavy metals, dominated by Silene vulgaris and 3) mesotrophic dominated by meadow species (Achillea millefolium, Plantago lanceolata, Hieracium pilosella, Taraxacum sp., Trifolium repens).

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Effect of precipitation on the dissipation, efficacy and selectivity of three chloroacetamide herbicides in sunflower

Plant Soil and Environment ◽

10.17221/750/2012-pse ◽

2013 ◽

Vol 59 (No. 4) ◽

pp. 175-182 ◽

Cited By ~ 11

Author(s):

M. Jursík ◽

M. Kočárek ◽

K. Hamouzová ◽

J. Soukup ◽

V. Venclová

Keyword(s):

Active Ingredient ◽

Field Trial ◽

Chenopodium Album ◽

Soil Layer ◽

Growing Season ◽

Amaranthus Retroflexus ◽

Low Level ◽

Small Plot ◽

Higher Temperature ◽

The Mean

The aim was to compare the efficacy, selectivity to sunflower and dissipation of three chloracetamide herbicides (acetochlor, metolachlor and pethoxamid) in dependence on precipitation after application. A small plot field trial was carried out with sunflower in Central Bohemia in 2010 and 2011. The remaining concentration of active ingredient in the soil of all studied herbicides was lower in the year with a higher temperature and a low level of total natural precipitation at the beginning of the growing season. Higher leaching of metolachlor and pethoxamid was recorded in irrigated plots. No leaching was found in the case of acetochlor. The highest leaching was found for metolachlor (9.2–25.5% in soil layer 5–10 cm). The highest phytotoxicity was found for acetochlor (9.8%) > pethox-amid (4.6%) > metolachlor (1.8%). The mean phytotoxicity in the irrigated plots was 6.9%, compared with 3.9% in the non-irrigated plots. The efficacy of the tested herbicide was affected by wet conditions. The highest efficacy on Chenopodium album, Amaranthus retroflexus, Echinochloa crus-galli and Solanum physalifolium was recorded after application of acetochlor and irrigation.

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SPECIES COMPOSITION OF WEEDS IN RAPESEED CROPS IN GEOGRAPHICALLY REMOTE REGIONS ON THE EXAMPLE OF LIPETSK AND SVERDLOVSK REGIONS

Agro-industrial technologies of the Central Russia ◽

10.24888/2541-7835-2020-18-96-107 ◽

2020 ◽

Vol 18 (4) ◽

pp. 96-107

Author(s):

N.N. Luneva ◽

◽

A.S. Tret'yakova ◽

P.V. Kondratkov ◽

V.L. Zakharov ◽

...

Keyword(s):

Species Composition ◽

Chenopodium Album ◽

Raphanus Raphanistrum ◽

Stellaria Media ◽

Echinochloa Crusgalli ◽

Erodium Cicutarium ◽

Thlaspi Arvense ◽

Species Similarity ◽

Silene Pratensis ◽

Heat And Moisture

The aim of the study is to identify differences in the species composition of weeds in spring rapeseed crops in two geographically remote regions of the Russian Federation – Lipetsk (Central black earth region) and Sverdlovsk (Ural region). The analysis was carried out using methods of comparative Floristics and distribution of species by classes of constancy of occurrence. Differences between segetal weed flora elements in the agrophytocenoses of canola compare regions, as in floral structure, consisting of the first two "triads" of the floristic spectra and confirmed the low rate coefficient of species similarity. Species differences are represented by species that pollute rapeseed crops only in one of the compared regions. Among the species common to the agrophytocenoses of rapeseed in the two regions are such species as, Chenopodium album L., Echinochloa crusgalli (L.) Beauv., Silene praténsis (Rafn) Godr., Euphorbia helioscopia L, Fallopia convolvulus (L.) A. Loeve, Viola arvensis Murr. they are characterized by higher rates of occurrence in the Lipetsk region, and Capsella bursa-pastoris (L.) Medik., Cirsium setosum (Willd.) Bess, Erodium cicutarium (L.) L. Her., Thlaspi arvense L. – in the Sverdlovsk region. The dominant species in the Lipetsk region are Raphanus raphanistrum L., Chenopodium album L., Echinochloa crusgalli (L.) Beauv., Silene praténsis (Rafn) Godr., and in the Sverdlovsk region - Galium vaillantii DC., Stellaria media (L.) Vill., Capsella bursa-pastoris (L.) Medik., Thlaspi arvense L., Chenopodium album L., Cirsium setosum (Willd.) Bess. To protect rapeseed crops from weeds in different regions that differ in terms of heat and moisture availability, it is necessary to develop regional protection systems, preceded by mandatory monitoring studies.

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