Competitive ability of corn in coexistence with goosegrass

Competition between plants is one of the main interferences that occurs in agricultural systems and accounts for significant crop yield reductions. The aim of this study was to assess the competitive ability of corn in coexistence with the weed species Eleusine indica. The experiments were conducted in a greenhouse, in the growing season 2010/2011, and were arranged in a completely randomized design with four replications. The experimental units consisted of plastic pots with a volumetric capacity of 8 L. Treatments were arranged in a replacement series with five proportions of corn plants and weed: 100:0, 75:25, 50:50, 25:75, and 0:100, respectively, with a constant population of eight plants per pot, at the end of each treatment. The competitiveness analysis was conducted through diagrams applied to the replacement series experiment and competitiveness index, and the variables evaluated were root, shoot, and total dry mass, and plant height. When in equal proportions, corn showed competitive ability equivalent to goosegrass in relation to the variables shoot, root, and total dry mass. Goosegrass was more competitive than the crop in relation to plant height.

Download Full-text

Competitiveness of alexandergrass or Bengal dayflower with soybean

Planta Daninha ◽

10.1590/s0100-83582010000300008 ◽

2010 ◽

Vol 28 (3) ◽

pp. 515-522 ◽

Cited By ~ 7

Author(s):

A.C.R. Dias ◽

S.J.P. Carvalho ◽

L.W. Marcolini ◽

M.S.C. Melo ◽

P.J. Christoffoleti

Keyword(s):

Competitive Ability ◽

Dry Mass ◽

Total Density ◽

Weed Species ◽

Replacement Series ◽

Commelina Benghalensis ◽

Randomized Design ◽

Full Flowering ◽

Completely Randomized Design ◽

Soybean Plants

Weeds compete with field crops mainly for water, light and nutrients, and the degree of competition is affected by the weed density and the intrinsic competitive ability of each plant species in coexistence. The objective of this research was to compare the competitiveness of alexandergrass (Brachiaria plantaginea) or Bengal dayflower (Commelina benghalensis) in coexistence with soybean, cv. M-Soy 8045. A factorial experiment (2 x 5) with two weed species and five competition proportions was carried out in a completely randomized design with four replicates. Proportions were based on a replacement series competition design, always maintaining the total density of four plants per 10 L plastic pots, which corresponded to 60 plants m ². The weed-crop proportions were: 0:4; 1:3; 2:2; 3:1; 4:0; that corresponded to the proportion of 100, 75, 50, 25 and 0% of soybean plants and the opposite for weeds, B. plantaginea or C. benghalensis plants. Leaf area, shoot dry mass of the weeds and soybean and number of soybean trifoliate leaves were evaluated when the soybean reached the phenologic stage of full flowering. B. plantaginea was a better competitor than soybean plants. Otherwise, C. benghalensis revealed a similar competitive ability that of the soybean. In both cases, there were evidences that intraspecific competition was more important.

Download Full-text

Does the resistance to glyphosate herbicide affect the competitive ability of ryegrass with soybean?

Planta Daninha ◽

10.1590/s0100-83582014000100021 ◽

2014 ◽

Vol 32 (1) ◽

pp. 189-196 ◽

Cited By ~ 2

Author(s):

C. Oliveira ◽

D. Agostinetto ◽

L. Vargas ◽

L.A. Ávila ◽

C.P. Tarouco

Keyword(s):

Statistical Analysis ◽

Leaf Area ◽

Intraspecific Competition ◽

Competitive Ability ◽

Dry Mass ◽

Replacement Series ◽

Soybean Crop ◽

Randomized Design ◽

Glyphosate Herbicide ◽

Completely Randomized Design

The objective this work was to investigate the competitive ability between resistant and susceptible ryegrass biotypes and of these with soybean crop. Four experiments were carried under greenhouse, in a completely randomized design with four replications, in 2011 and 2012. Treatments were arranged in additive series and replacement series assay. In each series, the proportions among ryegrass resistant and susceptible plants related to soybean were: 100:0, 75:25, 50:50, 25:75 e 0:100. Leaf area and shoot dry mass were evaluated. Competitiveness statistical analysis consisted in applying diagrams to the replacement series and alternative interpretations of the competitiveness indexes. The soybean crop had equivalent competitiveness to the susceptible ryegrass biotype and inferior to the resistant biotype, while the biotypes, both susceptible and resistant to glyphosate, present equivalent competitive ability. In general, the intraspecific competition is more harmful to ryegrass when in competition with soybean, while interspecific competition is predominant for culture.

Download Full-text

COMPETITIVE ABILITY OF CANOLA HYBRIDS WITH WEEDS

Planta Daninha ◽

10.1590/s0100-83582015000300004 ◽

2015 ◽

Vol 33 (3) ◽

pp. 413-423 ◽

Cited By ~ 2

Author(s):

L. GALON ◽

L. R. AGAZZI ◽

L. VARGAS ◽

F. NONEMACHER ◽

F. J. M. BASSO ◽

...

Keyword(s):

Leaf Area ◽

Competitive Analysis ◽

Raphanus Sativus ◽

Competitive Ability ◽

Lolium Multiflorum ◽

Dry Mass ◽

Replacement Series ◽

Randomized Design ◽

Competition Ability ◽

Completely Randomized Design

ABSTRACTThe objective of the study was to assess the relative competitive ability of canola hybrids in the presence of turnip (Raphanus sativus) and ryegrass (Lolium multiflorum) in different ratios of plants in the mixture. The experiments were conducted in a greenhouse, in a completely randomized design with four replications. Treatments were arranged in ratios of canola against turnip or ryegrass: 100:0, 75:25, 50:50, 25:75 and 0:100. Competitive analysis of the species was accomplished by means of diagrams usually applied to replacement series and also by the relative competitiveness indices. Fifty days after the emergence of the species, measurements of leaf area and shoot dry mass were performed. There was a competition between canola hybrids and weeds, with reduction for all variables. There was a differential competitive ability among canola hybrids in the presence of turnip and/or ryegrass. Canola hybrid Hyola 433 was more competitive in the presence of turnip than Hyola 61, 76 and 571 CL. Hyola 61, 76, 433 and 571 CL do not differ in terms of competition ability when growing with ryegrass.

Download Full-text

Competitive interaction between commom black bean cultivars and Euphorbia heterophylla 1

Pesquisa Agropecuária Tropical ◽

10.1590/1983-40632018v4851669 ◽

2018 ◽

Vol 48 (3) ◽

pp. 254-260 ◽

Cited By ~ 1

Author(s):

Leandro Galon ◽

César Tiago Forte ◽

Francisco Wilson Reichert Júnior ◽

Ricardo Trevisol ◽

Gismael Francisco Perin

Keyword(s):

Leaf Area ◽

Chlorophyll Content ◽

Plant Height ◽

Growth And Development ◽

Competitive Ability ◽

Dry Mass ◽

Black Bean ◽

Randomized Design ◽

Bean Plants ◽

Completely Randomized Design

ABSTRACT Weeds can interfere in the growth and development of bean plants if not properly managed, especially the wild poinsettia (Euphorbia heterophylla L.). This study aimed to evaluate the competitive ability of black bean cultivars coexisting with wild poinsettia. The experiment was conducted in a greenhouse, in a completely randomized design, with four replications. Each treatment consisted of one bean plant of the BRS Campeiro, IPR Uirapuru or SCS Predileto cultivars, living with 0, 1, 2, 3, 4 or 5 wild poinsettia plants, corresponding to populations of 0 plants m-2, 22 plants m-2, 44 plants m-2, 66 plants m-2, 88 plants m-2 and 110 plants m-2. Bean and wild poinsettia plants were assessed for stem diameter, leaf area, chlorophyll content, plant height and shoot dry mass. The bean cultivars behaved differently when cultivated with distinct wild poinsettia populations. The SCS Predileto cultivar showed a higher competitive ability against the wild poinsettia than the BRS Campeiro and IPR Uirapuru, what can be verified by the reduction of leaf area and dry mass of the weed. On average, at a density of 110 plants m-2, the wild poinsettia reduces in approximately 32 % the leaf area and 50 % the dry mass of the bean plants.

Download Full-text

INFLUENCE OF SUGARCANE STRAW AND SOWING DEPTH ON THE EMERGENCE OF WEED SPECIES

Planta Daninha ◽

10.1590/s0100-83582015000300003 ◽

2015 ◽

Vol 33 (3) ◽

pp. 405-412 ◽

Cited By ~ 2

Author(s):

P. V. SILVA ◽

P. A. MONQUERO ◽

F. B. SILVA ◽

N. C. BEVILAQUA ◽

M. R. MALARDO

Keyword(s):

Ricinus Communis ◽

Seedling Emergence ◽

Dry Mass ◽

Weed Species ◽

Sowing Depth ◽

Sugarcane Straw ◽

Randomized Design ◽

Significant Difference ◽

Completely Randomized Design ◽

Luffa Aegyptiaca

ABSTRACT This study aimed to understand the influence of sowing depth and the amount of sugarcane straw on the emergence of weed species Luffa aegyptiaca Miller (Cucurbitaceae); Mucuna aterrima Piper & Tracy (Fabaceae - Leguminosae) and Ricinus communis (Euphorbiaceae). A completely randomized design with a 5 x 4 x 3 factorial layout with four replications was used, at five sowing depths (0, 2, 4, 8 and 10 cm), four different amounts of sugarcane straw (0, 5, 10 and 15 t ha-1) and three different evaluation periods (7, 14 and 21 days after sowing). After sowing, different amounts of sugarcane straw (0, 5, 10 and 15 t ha-1) were deposited on soil. Seedling emergence was analyzed at 7, 14 and 21 days after sowing, counting the number of seedlings that had emerged. At the end of the trial, weed height (cm), leaf area (cm2) and shoot dry mass (g) were measured. In relation to emergence ability, studied species presented different responses according to sowing depth and to the amount of sugarcane straw deposited on the soil. For the L.aegyptiacaand M.aterrima, no significant difference was observed in the interaction between depth and sugarcane straw, showing the adaptation of these species to no-burn sugarcane system. For R.communis, seeds placed at 0 cm of sugar cane straw depth were observed to favor the emergence of seedlings.

Download Full-text

Interference of soybean and corn with Chloris distichophylla

Ciência e Agrotecnologia ◽

10.1590/s1413-70542013000400003 ◽

2013 ◽

Vol 37 (4) ◽

pp. 306-312 ◽

Cited By ~ 5

Author(s):

Alana Cristina Dorneles Wandscheer ◽

Mauro Antônio Rizzardi

Keyword(s):

Plant Height ◽

Dry Matter ◽

Total Density ◽

Weed Species ◽

Replacement Series ◽

Crop Season ◽

Crop Species ◽

Agricultural Ecosystems ◽

Corn Plants ◽

The University

In nature, plants interact with each other and establish positive, negative, and neutral interference relationships. In agricultural ecosystems, crops are usually affected by competition with weeds, and the effects of this process are influenced by the plant population density and proportional abundance and by the species involved. The present study evaluates the competitive interactions of soybean and corn with Chloris distichophylla. Two experiments were conducted in a greenhouse belonging to the University of Passo Fundo during the 2011/12 crop season: one experiment involving corn and C. distichophylla and another involving soybean and C. distichophylla. The experimental units were plastic pots, and the treatments were based on a replacement series, with a constant total density of eight plants per pot. The treatments included five combinations of soybean or corn plants with the weed species (8:0, 6:2, 4:4, 2:6 and 0:8), corresponding to relative abundances of 100, 75, 50, 25 and 0% of the crop species (and the reverse for the weed species). Competitiveness was analyzed using replacement-series experiment diagrams and competitive indices. Total dry matter and plant height were the two variables analyzed. The competitive indices indicated that corn and soybean crops were more competitive than the weed. The plant height was not affected by competition between both the species.

Download Full-text

Biochar as an alternative substrate for the production of sugarcane seedlings

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n12p826-832 ◽

2021 ◽

Vol 25 (12) ◽

pp. 826-832

Author(s):

Mauro F. C. Mota ◽

Eulina F. Damião ◽

Matheus R. Torres ◽

Rodinei F. Pegoraro ◽

Leidivan A. Frazão ◽

...

Keyword(s):

Particle Size ◽

Plant Height ◽

Dry Mass ◽

Leaf Length ◽

Particle Sizes ◽

Alternative Substrate ◽

Aerial Parts ◽

Randomized Design ◽

Completely Randomized Design ◽

Important Form

ABSTRACT Biochar, which has emerged as an important form of the transformation and final disposal of biomass, can be used directly in soil or in seedling nurseries. In this study, the use of biochar of different particle sizes and percentages was evaluated in replacement to a conventional substrate used in the production of sugarcane seedlings. To this end, an experiment was carried out based on a completely randomized design, with a 5 × 4 factorial scheme, consisting of five different percentages of biochar (with 0, 25, 50, 75, and 100% v/v substitution of the conventional substrate) and four particle sizes (<1, 2, 4, and 9 mm), with nine repetitions. As seedling growth variables, the average sprouting time, sprouting speed index, plant height, leaf number, leaf length, and width + 2, as well as the dry mass of the aerial parts and roots were evaluated. Irrespective of the percentage of commercial substrate replaced with biochar, sprouting time was found to be shorter when 6-mm-diameter biochar particles were used. With respect to the sprouting speed index, it was found that regardless of particle size, the highest value occurred when biochar was used to replace 42% of the commercial substrate. The substitution of the commercial substrate with biochar had the effect of reducing the growth of sugarcane seedlings.

Download Full-text

Interference of Brassicaceae and Poaceae on Canola Hybrids

Planta Daninha ◽

10.1590/s0100-83582019370100085 ◽

2019 ◽

Vol 37 ◽

Author(s):

D.R.O. SILVA ◽

A.C.M. AGUIAR ◽

D.P. GHELLER ◽

B.D. NOVELLO ◽

C.J. BASSO

Keyword(s):

Dry Matter ◽

Competitive Ability ◽

Shoot Growth ◽

Weed Species ◽

Orthogonal Contrasts ◽

Light Interference ◽

Randomized Design ◽

Number Of Leaves ◽

Hybrid Growth ◽

Completely Randomized Design

ABSTRACT: The objective of this study was to evaluate the initial competitive ability of canola hybrids against Brassicaceae and Poaceae species in terms of root and shoot resources. Two experiments were conducted in greenhouse, in a completely randomized design with four replications. The treatments consisted of interference conditions by root + shoot interference (root+shoot) and shoot interference (Light); and Brassicaceae and Poaceae weeds competing with hybrid of canola (Hyola 61 and Diamond) with different traits for competitiveness. The plant height, root length, dry matter of shoot and root, number of leaves and leaf area were evaluated. Data were compared using orthogonal contrasts. The turnip and volunteer canola reduced root development of the Hyola 61 in root + shoot interference, and among the Brassicaceas weeds, turnip caused greater losses. Brassicaceas weeds caused largest reductions in Diamond’s hybrid growth compared to Poaceae, mainly under light interference. Brassicaceas and Poaceae weeds cause similar damage to Hyola 61 hybrid, and the injury is higher for root +shoot interference. The black oat induce shoot growth in the Diamond hybrid under shoot interference, while among the Brassicaceae weed species, there were no differences.

Download Full-text

MANAGEMENT OF VOLUNTEER CASTOR BEAN IN THE GLYPHOSATE-RESISTANT SOYBEAN CROP

Planta Daninha ◽

10.1590/s0100-83582016340300015 ◽

2016 ◽

Vol 34 (3) ◽

pp. 545-553 ◽

Cited By ~ 2

Author(s):

V.S. ROCHA ◽

A.G.F. COSTA ◽

D.M.B.M. TROVÃO ◽

J.H. ZONTA ◽

V. SOFIATTI ◽

...

Keyword(s):

Leaf Area ◽

Plant Height ◽

Castor Bean ◽

Dry Mass ◽

Stem Diameter ◽

Root Volume ◽

Soybean Crop ◽

Randomized Design ◽

Chlorimuron Ethyl ◽

Completely Randomized Design

ABSTRACT The goal of this study was to evaluate the management of volunteer castor bean with herbicide applications used in pre and post-seeding of soybean crop resistant to glyphosate. Two experiments were conducted in a greenhouse in a completely randomized design with three replications. The first experiment corresponded to applications of desiccation with treatments: glyphosate (1,080 g ha-1); glyphosate + 2,4-D (1,080 + 670 g ha-1); glyphosate + carfentrazone-ethtyl (1,080 + 20 g ha-1); glyphosate + flumioxazin (1,080 + 25 g ha-1); glyphosate + saflufenacil (1,080 + 35 g ha-1); glyphosate + chlorimuron-ethyl (1,080 + 12.5 g ha-1); diuron + paraquat (300 + 600 g ha-1); and the control without application. In the second experiment, the treatments corresponded to doses of 0, 90, 180, 360, 720, 1,440, 2,880 and 5,760 g ha-1 of glyphosate for applications in post-emergence in soybean RR. The applications took place when the castor bean plant had four to six true leaves. The evaluations done in both experiments were: control and plant height at 7, 14 and 21 days after application (DAA); and stem diameter, leaf area, root volume, dry mass of shoots and roots at 21 DAA. The treatments with diuron + paraquat and glyphosate associated with 2,4-D, carfentrazoneethyl, flumioxazin or saflufenacil are more efficient for castor bean control in desiccation in pre-seeding of soybean. Glyphosate doses from 720 g ha-1 are effective to control castor bean in post-emergence of the glyphosate-resistant soybean crop.

Download Full-text

COMPETITIVE ABILITY OF WHEAT IN ASSOCIATION WITH BIOTYPES OF Raphanus raphanistrum L. RESISTANT AND SUSCEPTIBLE TO ALS-INHIBITOR HERBICIDES

Ciência e Agrotecnologia ◽

10.1590/s1413-70542015000200003 ◽

2015 ◽

Vol 39 (2) ◽

pp. 121-130 ◽

Cited By ~ 3

Author(s):

Leandro Oliveira da Costa ◽

Mauro Antônio Rizzardi

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Competitive Ability ◽

Management Strategies ◽

Raphanus Raphanistrum ◽

Replacement Series ◽

Herbicide Resistant ◽

Randomized Design ◽

Completely Randomized Design ◽

Als Inhibitor

The occurrence of Raphanus raphanistrum ALS herbicide-resistant in wheat crops causes crop yield losses, which makes it necessary to understand the factors that influence the interference of this weed to develop safer management strategies. This study aimed to evaluate the competitive ability of wheat in coexistence with biotypes of R. raphanistrum that are resistant (R biotype) and susceptible (S biotypes) to ALS herbicides and to determine whether there are differences in the competitiveness of these biotypes. The experiments were conducted in a greenhouse using a completely randomized design with four replications. The treatments were placed in pots and arranged in replacement series for three experiments (1 - wheat with the R biotype; 2 - wheat with the S biotype; and 3 - the R biotype with the S biotype) at the following ratios: 100:0, 75:25, 50:50, 25:75, and 0:100. The competitiveness was analyzed through diagrams applied to replacement experiments and competitiveness indices, including the evaluation of the shoot dry matter of the plants (experiments 1, 2, and 3) and the leaf area (experiment 3). The R and S biotypes significantly decreased the shoot dry matter of the wheat cultivar and demonstrated superior competitive ability compared with the culture. The interspecific competition was more important for the wheat and for the S biotype. The competitiveness of the R biotype compared to the S biotype was similar, with synergism in the leaf area production, which indicates the predominant intraspecific competition exhibited by the R biotype.

Download Full-text