Redroot Pigweed (Amaranthus retroflexus) Seedling Emergence and Growth in Soils Amended with Composted Dairy Cattle Manure and Fresh Dairy Cattle Manure under Greenhouse Conditions

Organic soil amendments are known to affect the composition and density of annual weed communities. The objective of this research was to measure the effect on emergence and growth of redroot pigweed seedlings when soil was amended with composted dairy manure at 18, 36, and 54 T/ha, or with raw dairy manure at 41, 82, and 123 T/ha. Data recorded (1) seedling emergence over 12 days, (2) number of leaves and total leaf area, (3) shoot and root dry weight, and (4) seed number. Maximum seedling emergence (32%) occurred in nonamended soil (the control). Emergence declined in a linear fashion when soil was amended with manure or with compost. Compost additions affected seedling emergence more severely than did manure additions. For every measure of redroot pigweed growth except seed production, amendment with manure at 123 T/ha retarded growth compared to soil alone or compost-amended mixes. Manure applied at 82 T/ha reduced leaf area and plant height relative to other treatments. Growth of redroot pigweed in soil amended with compost at 36 and 54 T/ha was always equal to or greater than growth in soil that was not amended. Seed production in one of two runs of the experiment was more than double in soils amended with compost at 36 and 54 T/ha compared to the nonamended soil. These results suggest that amending soils with raw dairy manure may decrease the competitiveness of redroot pigweed, whereas amending with composted manure is likely to increase competitiveness.

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Exogenous Antioxidants Enhance Seedling Growth and Yield of Artificially Aged Cabbage and Lettuce Seeds

Horticulturae ◽

10.3390/horticulturae7090274 ◽

2021 ◽

Vol 7 (9) ◽

pp. 274

Author(s):

Ademola Adetunji ◽

Sershen ◽

Boby Varghese ◽

Norman Pammenter

Keyword(s):

Leaf Area ◽

Seedling Growth ◽

Seedling Emergence ◽

Dry Weight ◽

Growth And Yield ◽

Seed Vigour ◽

Beneficial Effects ◽

Shoot Dry Weight ◽

Antioxidant Defence System ◽

Aged Seeds

Aged seeds exhibit compromised vigour in terms of germination, seedling emergence and growth, but this can to some extent be alleviated by invigoration treatments before sowing. This study aimed to investigate ageing rates and patterns in cabbage (Brassica oleraceae) and lettuce (Lactuca sativa) seeds and whether the beneficial effects of invigorating aged seeds with exogenous antioxidants translate to enhanced seedling performance. Seeds were artificially aged to 25% viability before soaking in 0.4 mM glycerol, 0.6 mM GSH and 0.2 mM trolox for cabbage, and 0.6 mM glycerol, GSH and trolox for lettuce; deionised water served as a control. After 14 days of sowing, seedling emergence percentage, mean emergence time, mean daily emergence, and time taken to 25% emergence were computed. Seedling vigour index, root and shoot dry weight, root:shoot ratio, leaf area, leaf area ratio, and leaf chlorophyll content were assessed 6 weeks after sowing. Furthermore, the photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (E), and chlorophyll fluorescence were measured 6 weeks after sowing. Notably, ageing resulted in the loss of seed vigour and viability at higher rates in lettuce than cabbage. Seed pretreatment with glycerol promoted seedling growth in both species and shoot dry weight in lettuce, while glycerol and GSH enhanced Pn, Gs and E in lettuce. Trolox also enhanced Pn and E in lettuce. The beneficial effects of the antioxidant treatments are thought to be associated with the protection of photosystems from oxidative stress and/or stimulation of enzymes involved in photosynthesis, possibly through an enhanced antioxidant defence system during the early development stages when seedlings are particularly vulnerable to stress.

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Stimulation of Common Cocklebur (Xanthium pensylvanicum) and Redroot Pigweed (Amaranthus retroflexus) Seed Germination by Injections of Ethylene into Soil

Weed Science ◽

10.1017/s0043174500061129 ◽

1980 ◽

Vol 28 (5) ◽

pp. 510-514 ◽

Cited By ~ 18

Author(s):

G. H. Egley

Keyword(s):

Seed Germination ◽

Laboratory Tests ◽

Seedling Emergence ◽

Amaranthus Retroflexus ◽

Redroot Pigweed ◽

Plastic Bags ◽

Viable Seeds ◽

Chamber Studies ◽

Growth Chamber Studies ◽

Stimulation Of

The effects of ethylene upon germination of common cocklebur (Xanthium pensylvanicumWallr.) and redroot pigweed (Amaranthus retroflexusL.) seeds were studied. In laboratory tests with seeds in sealed flasks in the dark, 10 μl/L ethylene increased germination of redroot pigweed seeds from 7% to 52% at 30 C, and increased germination of large and small common cocklebur seeds from 30% and 0% to 100% and 90% respectively, at 25 C. At least 12 h of exposure to ethylene was necessary for appreciable stimulation of germination. In growth chamber studies with known numbers of seeds in pots of soil, ethylene at 11 kg/ha was injected into the soil, and the pots were enclosed in plastic bags for 24 h. One such injection at 2 weeks after planting, and successive injections at 2, 3, and 4 weeks, significantly increased redroot pigweed seedling emergence, and significantly decreased the numbers of dormant, viable seeds remaining in the soil. When pots were not enclosed, injections did not significantly effect redroot pigweed seeds, but significantly increased common cocklebur seedling emergence and decreased the number of viable common cocklebur seeds remaining in the soil.

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Interference of Redroot Pigweed (Amaranthus retroflexus) in Corn (Zea mays)

Weed Science ◽

10.1017/s0043174500076967 ◽

1994 ◽

Vol 42 (4) ◽

pp. 568-573 ◽

Cited By ~ 131

Author(s):

Stevan Z. Knezevic ◽

Stephan F. Weise ◽

Clarence J. Swanton

Keyword(s):

Zea Mays ◽

Grain Yield ◽

Seed Production ◽

Field Experiments ◽

Amaranthus Retroflexus ◽

Corn Yield ◽

Leaf Stage ◽

Redroot Pigweed ◽

Emergence Date

Redroot pigweed is a major weed in corn throughout Ontario. Field experiments were conducted at two locations in 1991 and 1992 to determine the influence of selected densities and emergence times of redroot pigweed on corn growth and grain yield. Redroot pigweed densities of 0.5, 1, 2, 4 and 8 plants per m of row were established within 12.5 cm on either side of the corn row. In both years, redroot pigweed seeds were planted concurrently and with corn at the 3- to 5-leaf stage of corn growth. A density of 0.5 redroot pigweed per m of row from the first (earlier) emergence date of pigweed (in most cases, up to the 4-leaf stage of corn) or four redroot pigweed per m of row from the second (later) emergence date of pigweed (in most cases, between the 4- and 7-leaf stage of corn) reduced corn yield by 5%. Redroot pigweed emerging after the 7-leaf stage of corn growth did not reduce yield. Redroot pigweed seed production was dependent upon its density and time of emergence. The time of redroot pigweed emergence, relative to corn, may be more important than its density in assessing the need for postemergence control.

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Dog mustard (Erucastrum gallicum) response to crop competition

Weed Science ◽

10.1017/s0043174500093048 ◽

1997 ◽

Vol 45 (3) ◽

pp. 397-403

Author(s):

David A. Wall

Keyword(s):

Interspecific Competition ◽

Leaf Area ◽

Seed Production ◽

Growth And Development ◽

Dry Weight ◽

Field Studies ◽

Limiting Factor ◽

Shoot Dry Weight ◽

Summer Fallow ◽

Crop Competition

Greenhouse studies suggested that dog mustard was less competitive than wheat, but of similar competitiveness to flax. In field studies, dog mustard growth and development were markedly affected by crop competition. Competition from flax and wheat reduced dog mustard leaf area, shoot dry weight, plant height, and seed production compared with the weed grown on summer-fallow. Dog mustard was a prolific seed producer when grown in the absence of interspecific competition. On summer-fallow, dog mustard produced as many as 79,100 seeds plant−1when moisture was not a limiting factor. However, average seed production was 19,400 and 8000 seeds plant−1in 1994 and 1995, respectively.

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Coir as an Alternative to Peat in Media for Tomato Transplant Production

HortScience ◽

10.21273/hortsci.37.2.309 ◽

2002 ◽

Vol 37 (2) ◽

pp. 309-312 ◽

Cited By ~ 40

Author(s):

M. Arenas ◽

C.S. Vavrina ◽

J.A. Cornell ◽

E.A. Hanlon ◽

G.J. Hochmuth

Keyword(s):

Leaf Area ◽

Seedling Emergence ◽

C:N Ratio ◽

Dry Weight ◽

Medium Composition ◽

Stem Diameter ◽

Tomato Seed ◽

Root Dry Weight ◽

Growth Differences ◽

Summer Fruit

Sixteen media prepared from peat, coir, vermiculite, or perlite were used to determine the optimum growing media for tomato (Lycopersicum esculentum Mill.) transplants. Medium composition did not affect tomato seed emergence, although seedling emergence was higher in winter (90%) than summer (85%). Greatest transplant root dry weight, stem diameter, and leaf area were achieved in 50% to 75% peat + 25% to 50% vermiculite in summer. In winter, greatest transplant root dry weight, stem diameter, and leaf area were achieved in eight media: 100% peat, 75% peat + 25% vermiculite, 75% peat + 25% perlite, 50% peat + 50% vermiculite, 50% peat + 50% perlite, 25% peat + 50% coir + 25% vermiculite, 50% peat + 25%coir + 25% vermiculite, and 25% peat +25% coir +25% vermiculite +25% perlite. Transplants grown with >50% coir exhibited reduced plant growth compared to peat-grown transplants, a response that may be associated with high N immobilization by microorganisms and high C:N ratio. Despite transplant growth differences during the summer, fruit yields generally were unaffected by transplant media.

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Competition and Canopy Architecture as Affected by Soybean (Glycine max) Row Width and Density of Redroot Pigweed (Amaranthus retroflexus)

Weed Science ◽

10.1017/s0043174500055909 ◽

1989 ◽

Vol 37 (1) ◽

pp. 84-92 ◽

Cited By ~ 65

Author(s):

Anne Légère ◽

Marvin M. Schreiber

Keyword(s):

Leaf Area ◽

Distribution Patterns ◽

Field Trials ◽

Amaranthus Retroflexus ◽

Total Biomass ◽

Canopy Architecture ◽

Redroot Pigweed ◽

Row Width ◽

Narrow Row ◽

Soybean Leaves

The effects of soybean row width and redroot pigweed density on growth of crop and weed were studied in field trials in 1983, 1984, and Structural relationships within the canopies of soybean and redroot pigweed in relation to row width and weed density were studied in 1984 and 1985 to assess canopy geometry in relation to intra- and interspecific competition. Early in the growing season, soybean biomass was reduced in the presence of both high and low densities of pigweed. Pigweed biomass was also reduced in the presence of soybeans, especially when grown in narrow rows (25 cm). By midseason, pigweed's contribution to total biomass had reached 43% in wide-row (76-cm) stands and 24% in narrow rows. Soybean produced two to four times more leaf area than pigweed during the first half of the growth season. Narrow-row planting favored soybean leaf area production. Soybean LAI values from weedy stands were reduced compared to those from weed-free stands. Pigweed's contribution to total leaf area averaged 29% in wide-row spacing and 15% in narrow rows. Pigweed leaf area was concentrated in the upper strata of the canopy and thus reduced light available to soybean leaves lower in the canopy. Leaf area distribution patterns suggested that soybean and pigweed were competing for light even though soybean had produced more leaf area than pigweed. These relations were consistent from year to year in spite of variable water conditions.

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Effect of Seeding Systems and Dinitroaniline Herbicides on Emergence and Control of Rigid Ryegrass (Lolium Rigidum) in Wheat

Weed Technology ◽

10.1614/wt-06-016.1 ◽

2007 ◽

Vol 21 (1) ◽

pp. 53-58 ◽

Cited By ~ 30

Author(s):

Bhagirath S. Chauhan ◽

Gurjeet S. Gill ◽

Christopher Preston

Keyword(s):

Seed Production ◽

Dry Matter ◽

Seedling Emergence ◽

South Australia ◽

Dry Weight ◽

Soil Disturbance ◽

Yorke Peninsula ◽

Rigid Ryegrass ◽

And Control ◽

Dinitroaniline Herbicides

Experiments were conducted at Minlaton on the Yorke Peninsula of South Australia in 2004 and 2005 to study the effect of four different seeding systems and dinitroaniline herbicides on the seedling emergence and growth of rigid ryegrass in wheat. The seeding systems were low soil-disturbance discs (DayBreak and K-Hart) and high soil-disturbance tines (narrow point and Ribbon seeder); and the herbicides were oryzalin, pendimethalin, and trifluralin at rate of 0.72 kg ai/ha. The total seedling emergence of rigid ryegrass was higher in nontreated plots planted with the tines compared with the discs. In general, oryzalin was the least-effective herbicide in controlling emergence of rigid ryegrass. All herbicides were more effective in reducing the number of plants, spikes, dry matter, and seed production of rigid ryegrass in combination with tines than with discs. However, in the absence of herbicides, plant and spike numbers, plant dry weight, and seed production of rigid ryegrass were significantly lower where discs were used to sow, rather than tines. In the absence of herbicide, rigid ryegrass was less competitive with wheat under the disc-sown systems. The response of grain yield to herbicides was greater under the tine-sown systems than the disc-sown systems.

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The Interaction of Soybean (Glycine max) and Five Weed Species in the Greenhouse

Weed Science ◽

10.1017/s0043174500083065 ◽

1985 ◽

Vol 33 (5) ◽

pp. 669-672 ◽

Cited By ~ 10

Author(s):

Janet L. Shurtleff ◽

Harold D. Coble

Keyword(s):

Glycine Max ◽

Dry Matter ◽

Dry Weight ◽

Amaranthus Retroflexus ◽

Matter Content ◽

Dry Matter Content ◽

Weed Species ◽

Common Ragweed ◽

Common Lambsquarters ◽

Redroot Pigweed

The influence of relative planting date on the growth of common cocklebur (Xanthium pensylvanicumWallr. ♯ XANST), common ragweed (Ambrosia artemesiifoliaL. ♯ AMBEL), sicklepod (Cassia obtusifoliaL. ♯ CASOB), and redroot pigweed (Amaranthus retroflexusL. ♯ AMARE) grown in competition with soybean [Glycine max(L.) Merr. ‘Bragg’] was studied in the greenhouse. Increases in dry matter and height were slower for the five weed species than for soybean throughout the period of the study. The root: shoot ratio of soybean was the highest of any plant in the study, while common ragweed, common cocklebur, common lambsquarters, and sicklepod were intermediate, and redroot pigweed was the lowest. Soybean dry weight was always reduced when grown in competition with a weed. Soybean dry-matter production was reduced most when weeds were planted 2 weeks before soybean, especially with common cocklebur and common lambsquarters. Weed dry-matter content was severely reduced when the weed seed were planted simultaneously with or following soybean. Soybean height was usually reduced by competition with the weeds. The height of common ragweed was increased, however, when planted simultaneously with soybean. Common lambsquarters, redroot pigweed, and common ragweed heights were increased when planted 2 weeks prior to soybean.

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Responses of soybean and five weeds to CO2 enrichment under two temperature regimes

Canadian Journal of Plant Science ◽

10.4141/cjps93-164 ◽

1993 ◽

Vol 73 (4) ◽

pp. 1249-1260 ◽

Cited By ~ 19

Author(s):

David C. Tremmel ◽

David T. Patterson

Keyword(s):

Leaf Area ◽

Plant Biomass ◽

Co2 Enrichment ◽

Amaranthus Retroflexus ◽

Redroot Pigweed ◽

Temperature Regimes ◽

Elytrigia Repens ◽

Glycine Max L ◽

Two Temperatures ◽

Temperature Interaction

Rising atmospheric CO2 levels could affect plant growth both directly, through effects on physiology, and indirectly, through the effects of possible CO2-induced temperature increases. In this study we examined the interacting effects of CO2 enrichment and temperature on the growth and allocation of soybean and five weeds. Individual plants of soybean [Glycine max (L.) Merr. ’Braxton’], johnsongrass [Sorghum halepense (L.) Pers.], quackgrass [Elytrigia repens (L.) Nevski], redroot pigweed (Amaranthus retroflexus L.), sicklepod (Cassia obtusifolia L.), and velvetleaf (Abutilon theophrasti Medic.) were grown in growth chambers in all combinations of two temperatures (avg. day/night of 26/19 °C and 30/23 °C) and two CO2 concentrations (350 and 700 ppm) for 35 d. Leaf area and plant biomass were greater at higher temperatures, regardless of CO2 level, in all species except quackgrass. Quackgrass (C3) produced its greatest leaf area and biomass at elevated CO2, whereas johnsongrass (C4) showed little response. Redroot pigweed (C4) and the C3 dicotyledenous species (soybean, sicklepod, velvetleaf) produced their greatest biomass at high CO2, though effects on leaf area were less consistent or absent. In general, when significant CO2 by temperature interactions were found, CO2 responses were smallest at higher temperatures. These differential responses to elevated CO2 concentrations may cause changes in the relative importance of competitive pressure from these weeds. Key words: CO2 by temperature interaction, soybean, johnsongrass, quackgrass, redroot pigweed, sicklepod, velvetleaf

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Crescimento inicial de Erythrina velutina em diferentes substratos com adubação orgânica

Revista Verde de Agroecologia e Desenvolvimento Sustentável ◽

10.18378/rvads.v11i5.3594 ◽

2016 ◽

Vol 11 (5) ◽

pp. 30

Author(s):

Mychelle Karla Teixeira de Oliveira ◽

Jeferson Luiz Dallabona Dombroski ◽

Rita De Cássia Araújo de Medeiros ◽

Valmor Elias Tomczak ◽

Raul Martins de Farias

Keyword(s):

Growth Rate ◽

Leaf Area ◽

Folk Medicine ◽

Weight Ratio ◽

Dry Weight ◽

Cattle Manure ◽

Experimental Unit ◽

Initial Growth ◽

Organic Fertilization ◽

Basal Diameter

Erythrina velutina é uma espécie arbórea nativa do Nordeste Brasileiro, empregada no paisagismo, na regeneração de áreas degradadas e na medicina popular. Objetivou-se com este trabalho avaliar o crescimento de mudas de Erythrina velutina produzidas em substratos com adubação orgânica. O experimento foi conduzido em delineamento inteiramente casualizado, com parcelas subdivididas no tempo, com cinco repetições, sendo a unidade experimental representada por 20 mudas. O primeiro fator foi constituído por dois substratos (solo de Mossoró-RN + esterco bovino (4:1) e solo de Angicos-RN + esterco bovino (4:1)), e o segundo fator constituído de dois acessos. Ao longo do experimento foram realizadas coletas, para avaliação de crescimento (28, 56, 84, 112 e 140 dias após a semeadura), com intervalos de 28 dias. Em cada coleta, as mudas foram analisadas quanto ao comprimento da parte aérea, ao número de folhas, ao diâmetro de coleto, à área foliar, à massa da matéria seca (caule, folhas, raiz, parte aérea, relação da parte aérea e raiz, e total). Pode-se concluir que os acessos de Erythrina velutina tiveram crescimento rápido e uniforme quando produzidas nos dois substratos (solo de Mossoró-RN + esterco bovino curtido (4:1) e solo de Angicos-RN + esterco bovino curtido (4:1)).Initial growth of Erythrina velutina in different substrates with organic fertilization Abstract: Erythrina velutina is a tree native to the Brazilian northeast, used in landscaping, regeneration of degraded areas and in folk medicine. The objective of this work was to obtain information on Erythrina velutina of two accessions conducted in substrates with organic fertilization. The experiment was conducted in a completely randomized design with split plot with five replications and the experimental unit was represented by 20 seedlings. The first factor was composed of two substrates (sand + cattle manure (4:1) and soil + cattle manure (4:1)) and the second factor consisted of two accessions. Throughout the experiment were five collections of plants for evaluation of growth (28, 56, 84, 112 and 140 days after sowing), with intervals of 28 days. At each sampling date, the following characteristics were analyzed: shoot length, leaf number, basal diameter, leaf area, dry matter (aerial part, branches, leaves, roots, shoots, shoot to root dry weight ratio), leaf area ratio, leaf weight ratio, specific leaf area, absolute growth rate, relative growth rate and net assimilation rate. It can be concluded that accessions of Erythrina velutina grew fast and even when produced in the two substrates consisting of sand and / or soil with added manure.

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