Physiological Response of Maize and Weeds in Coexistence

ABSTRACT This study aimed at evaluating the physiology of maize and weeds when living under different densities. The randomized block design with 4 replications was used. The factorial scheme 5 x 2 + 1 and 5 x 3 was adopted, for maize and weeds respectively, corresponding to weed species (Bidens pilosa, Commelina benghalensis, Urochloa brizantha, Sorghum arundinaceum and Ipomoea triloba) and infestation density (control, 15 and 30 plants m-2). Weeds were kept in coexistence with the maize hybrid DKB 390 PRO 2, with an additional treatment for maize plants absent of competition. It was kept in coexistence with maize hybrid DKB 390 PRO 2 besides an additional treatment with maize plants absent of competition. On day 45 and 60 after maize planting (DAP) physiological reviews were performed within the culture, and 38 days after weed transplanting (DAT), an infrared gas analyzer (IRGA) was used. There were physiological changes in maize due to the coexistence with weeds. On day 45 DAP, the competition, regardless of the weed species, caused less photosynthetic rate in maize coexisting with 15 plants m-2; the stomatal conductance was lower in both densities. On day 60 DAP, maize in competition with 15 and 30 plants m-2 showed lower transpiration rate. U. brizantha and S. arundinaceum showed reduction in photosynthesis and transpiration, due to increased density and coexistence with maize.

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Weed interference on growth and yield of transgenic maize

Planta Daninha ◽

10.1590/s0100-83582014000300007 ◽

2014 ◽

Vol 32 (3) ◽

pp. 515-520 ◽

Cited By ~ 7

Author(s):

R.M. Faria ◽

R.E. Barros ◽

L.D. Tuffi Santos

Keyword(s):

Dry Matter ◽

Block Design ◽

Dry Mass ◽

Transgenic Maize ◽

Growth And Yield ◽

Dry Matter Accumulation ◽

Weed Species ◽

Bidens Pilosa ◽

Commelina Benghalensis ◽

Randomized Block Design

Plants kept under competition tend to modify their morphology to optimize the use of production factors. This study aimed to evaluate the effects of competition between transgenic maize and five weed species on the growth and yield of transgenic maize hybrid. The experiment used a randomized block design with four replicates in a factorial 5 x 2 + 6 scheme consisting of a combination of maize under competition with five weed species (Bidens pilosa, Commelina benghalensis, Brachiaria brizantha, Sorghum arundinaceum and Ipomoea triloba) in two weed densities (15 or 30 plants m-2) plus six treatments corresponding to maize and weed species without competition. All the means for dry matter accumulated by maize plants in the stem and leaf in the density of 15 plants m ² were higher than the means for plants in coexistence with 30 plants m-². Number of kernels, diameter and length of cob were not affected by competition with weeds. The weeds that most interfered with maize biomass production were S.arundinaceum and B.brizantha. Leaf dry mass accumulation was more sensitive than the production of stem. It was observed that maize was usually very competitive with weeds, and there was a strong decrease in dry matter accumulation of all the weeds in the study when in coexistence with the crop.

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Levels of nutrients and grain yield of maize intercropped with signalgrass (Brachiaria) in different arrangements of plants

Planta Daninha ◽

10.1590/s0100-83582015000100006 ◽

2015 ◽

Vol 33 (1) ◽

pp. 49-56 ◽

Cited By ~ 4

Author(s):

M.A.M. FREITAS ◽

D.V. VALADÃO SILVA ◽

M.F. SOUZA ◽

A.A. SILVA ◽

D.T. SARAIVA ◽

...

Keyword(s):

Grain Yield ◽

Field Experiments ◽

Block Design ◽

Matter Content ◽

Seeding Density ◽

Dry Matter Content ◽

Randomized Block Design ◽

Maize Plants ◽

Urochloa Brizantha ◽

Positive Effect

Competition between maize and signalgrass can economically cripple the intercropping by the reduced yield of maize and dry matter content of the forage. In seeking to define plant arrangements which make this system more efficient, this research was held with the objective of assessing the effects of interference of densities of signalgrass (Urochloa Brizantha) on nutrition and on maize grain yield. Two field experiments were conducted in a randomized block design with four replications. Treatments were arranged similarly in both experiments, in a 2 x 4 factorial design, the first factor being the dose of Nicosulfuron herbicide applied (0 and 8 g ha-1) and the second factor being the forage seeding rates (0, 2, 4 and 6 kg of seeds per hectare). The interference of signalgrass reduced foliar nitrogen, potassium and phosphorus content in maize plants intercropped with the forage. Higher values of grain yield were observed with the reduction of the spacing and the application of the recommended herbicide underdose (8 g ha-1). It was concluded that, regardless of the seeding density of U. Brizantha, reducing the maize seeding inter-rows spacing, combined with the application of an underdose of Nicosulfuron, caused a positive effect by reducing the initial forage growth, resulting in less interference of Urochloa brizantha on nutrient uptake by the maize plants and grain yield of the crop.

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MAIZE CROP PHYTOTOXICITY IN RESPONSE TO SUB-DOSES OF SULFOMETURON-METHYL

Planta Daninha ◽

10.1590/s0100-83582017350100067 ◽

2017 ◽

Vol 35 (0) ◽

Cited By ~ 1

Author(s):

P.A.C. FELISBERTO ◽

G. FELISBERTO ◽

A.R. RAMOS ◽

P.C. TIMOSSI

Keyword(s):

Field Experiment ◽

Block Design ◽

Development Stage ◽

Maize Crop ◽

Maize Hybrid ◽

Sulfometuron Methyl ◽

Development Stages ◽

Randomized Block Design ◽

Maize Plants ◽

Higher Doses

ABSTRACT The use of ripeners has been a common practice in the sugarcane culture. The application of these products is often performed through aerial spraying, which increases the chances of drifting of the ripeners- molecules over the surrounding crops, such as maize. In order to study possible phytointoxication on maize caused by sulfometuron-methyl application, a field experiment was conducted to evaluate the effects of sulfometuron-methyl sub doses on maize when applied at the V4 and V8 development stages. The experiment was installed in a randomized block design with four replications. The treatments followed a 2 x 5 factor scheme, with the first factor corresponding to development stages of maize during which the ripener was applied (V4 and V8) and the second factor was related to sulfometuronmethyl sub doses (0; 0.45; 0.90; 1.35 and 1.80 g a.i. ha 1). The maize crop showed phytotoxicity with the use of 0.45 g a.i. ha-1 of sulfometuron-methyl; it was more severe when the application occurred at the development stage V8, leading the plant to death at the highest used dose. Furthermore, it was also possible to observe negative changes in the morphological and production components of maize plants. The SYN 7G17 maize hybrid is highly susceptible to sulfometuron-methyl. The occurrence of sulfometuron-methyl deposits at higher doses or at different development stages of the crop may reflect more severe phytotoxic effects than the ones observed in this study.

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Pre-emergence application of (thio)urea analogues compromises the development of the weed species Bidens pilosa, Urochloa brizantha, and Urochloa decumbens

Journal of Advanced Research ◽

10.1016/j.jare.2019.01.017 ◽

2019 ◽

Vol 17 ◽

pp. 95-102

Author(s):

Dandara R. Muniz ◽

Janaina S. Garcia ◽

Taniris C. Braga ◽

Ângelo de Fátima ◽

Luzia V. Modolo

Keyword(s):

Weed Species ◽

Bidens Pilosa ◽

Urochloa Decumbens ◽

Urochloa Brizantha

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Yield of castor bean fertilized with sewage sludge and potassium and magnesium sulphate

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v19n8p773-779 ◽

2015 ◽

Vol 19 (8) ◽

pp. 773-779 ◽

Cited By ~ 2

Author(s):

Thâmara F. M. Cavalcanti ◽

Geraldo R. Zuba ◽

Regynaldo A. Sampaio ◽

João P. Carneiro ◽

Ely S. A. de Oliveira ◽

...

Keyword(s):

Organic Matter ◽

Sewage Sludge ◽

Castor Bean ◽

Block Design ◽

Additional Treatment ◽

Iron Copper ◽

Maximum Value ◽

Randomized Block Design ◽

N Requirement ◽

Bean Leaves

<title>ABSTRACT</title>The aim of this study was to evaluate the yield and nutrition of castor bean in response to fertilization with sewage sludge and potassium (K) and magnesium (Mg) sulphate. The experiment was carried out from January to July 2011. The treatments, in a randomized block design with three replicates, in a Nitosol, corresponded to a factorial scheme (2 x 4 +1): two doses of K and Mg sulphate combined with four doses of sewage sludge (0, 2.60, 5.20 and 10.40 t ha-1, dry basis), applied based on its nitrogen (N) content and the N requirement for the crop and an additional treatment with NPK. The castor bean grain yield fertilized with sewage sludge did not differ from conventional fertilization, with the maximum value achieved at a dose of 7.5 t ha-1 of sewage sludge. The fertilization with sewage sludge increased zinc and copper levels in the soil to values close to or higher than those in conventional fertilization, without any influence on the concentrations in the leaf. Fertilization with K and Mg sulphate increased the levels of these cations in the soil without affecting the concentrations in the leaves. The fertilization with sewage sludge increased the contents of organic matter, sulfur, zinc, iron, copper and boron in the soil, and manganese and boron in castor bean leaves.

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Cycle pruning programmed on the grain yield of arabica coffee

Ciência e Agrotecnologia ◽

10.1590/1413-7054201943014419 ◽

2019 ◽

Vol 43 ◽

Author(s):

Diego Corona Baitelle ◽

Abraão Carlos Verdin Filho ◽

Sílvio de Jesus Freitas ◽

Guilherme Bessa Miranda ◽

Henrique Duarte Vieira ◽

...

Keyword(s):

Block Design ◽

Management Strategies ◽

Production Capacity ◽

Additional Treatment ◽

Control Treatment ◽

Arabica Coffee ◽

Randomized Block Design ◽

Canopy Area ◽

Plagiotropic Branches ◽

Productive Development

ABSTRACT The cycle pruning programmed is a reinvigoration technique widely employed in Conilon coffee. This strategy may also be adopted for Arabica coffee to increase its crop longevity and yield. In this scenario, the present study proposes to examine the influence of the cycle pruning programmed on the vegetative and productive development of Arabica coffee. The experiment was developed in the field as a randomized-block design with four replicates. Treatments were tested in a 4 × 2 factorial arrangement consisting of four stem densities (4000, 8000, 12000 or 16000 stems ha-1) and two management strategies for the removal of plagiotropic branches (annual or biennial removal of branches which had reached 70% or more of their production capacity). For some variables, the treatments were organized as a 4 × 2 × 2 factorial arrangement in which the last factor corresponded to two regions of data collection in the plant (upper or lower). For all factorial arrangements, an additional treatment (control) was employed corresponding to traditional pruning (recepa). Annual or biennial removal of plagiotropic branches which had attained 70% or more of their production capacity can be adopted with no losses to crop yield. The cycle pruning programmed improves the distribution of branches, increases canopy area and prevents the occurrence of the “naked neck” phenomenon, observed in control treatment. Additionally, it provides better agronomic and productive performance; therefore, it can be used as a substitute for recepa.

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Economic Feasibility of Chemical Weed Control in Soybean Production in Serbia

Agronomy ◽

10.3390/agronomy10020291 ◽

2020 ◽

Vol 10 (2) ◽

pp. 291 ◽

Cited By ~ 3

Author(s):

Maja Meseldžija ◽

Miloš Rajković ◽

Milica Dudić ◽

Milica Vranešević ◽

Atila Bezdan ◽

...

Keyword(s):

Weed Control ◽

Block Design ◽

Economic Feasibility ◽

Economic Injury Level ◽

Weed Species ◽

Soybean Crop ◽

Economic Justification ◽

Randomized Block Design ◽

Effective Combination ◽

Economic Injury

The aim of this study was to investigate the efficacy and phytotoxicity of herbicides in combinations and to determine their economic feasibility in the soybean crop. The trials were placed at two locations, Pobeda and Budisava (Serbia), during 2016 and 2018, organized in a randomized block design with four replicates of all herbicide combinations (metribuzin + S-metolachlor; imazamox + oxasulfuron + typhenesulfuron-methyl; metribuzin + S-metolachlor + imazamox + oxasulfuron + typhenesulfuron-methyl; and bentazon + imazamox + typhenesulfuron-methyl). At the first location, 16 weed species were determined, while in the second location, 14 were determined. The highest reduction in the number of weeds was achieved at the first location, using a combination of herbicides metribuzin + S-metolachlor + imazamox + oxasulfuron + typhenesulfuron-methyl with a total efficacy that ranged from 96.98% to 97.40%. Only on the second location bentazone + imazamox + tifensulfuron-methyl showed passable phytotoxicity on soybean, during both years. Based on the established economic justification, in the combinations of metribuzin + S-metolachlor + imazamox + oxasulfuron + typhenesulfuron-methyl, yield was increased for 2350 kg/ha or 1.91 times more, according to the untreated variant at first location. The economic injury level at the most effective combination of herbicides was 52.70 weeds/m2.

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Determination of the treatment period of banana seedlings with rhizobacteria in the control of Meloidogyne javanica

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452018423 ◽

2018 ◽

Vol 40 (4) ◽

Author(s):

Pollyanna Santiago Lopes ◽

Regina Cássia Ferreira Ribeiro ◽

Adelica Aparecida Xavier ◽

Leandro de Souza Rocha ◽

Edson Hiydu Mizobutsi

Keyword(s):

Treatment Period ◽

Dry Matter ◽

Treatment Time ◽

Block Design ◽

Meloidogyne Javanica ◽

Additional Treatment ◽

Reproductive Capacity ◽

Egg Mass ◽

Randomized Block Design ◽

Set Up

Abstract The introduction of rhizobacteria to the soil can be done via treatment of propagating materials. The aim of this work was to evaluate in greenhouse the influence of immersion periods of micropropagated ‘Prata-Anã’ banana seedling roots in suspension of different rhizobacterial isolates on the growth of seedlings and control of Meloidogyne javanica. The experiment was set up in greenhouse in a randomized block design in a 10 x 2 factorial scheme (rhizobacteria isolates) x (immersion periods: 60 and 120 minutes) with 10 replicates. The additional treatment (control) was composed of seedlings without any treatment infected with M. javanica. Treated seedlings were planted in pots containing soil: previously autoclaved sand. After twenty-four hours, suspension containing 3,000 M. javanica eggs was added to the soil. At 60 days, number of galls, egg mass and eggs per root system, number of second-stage juveniles (J2) per 100 cm3 of soil were evaluated and the reproduction factor was calculated. Shoot dry matter mass was also evaluated. Of the four rhizobacteria that reduced the reproductive capacity of the nematode, three were more efficient when seedlings were treated for 120 minutes. The treatment period of banana seedlings did not affect the shoot dry matter yield and all rhizobacteria increased the dry matter weight of seedlings infected with Meloidogyne javanica. It could be concluded that rhizobacteria have different treatment time requirements for seedlings to control the nematode, but do not interfere with the development of seedlings.

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PENGARUH DOSIS PUPUK UREA DAN PUPUK HAYATI MIKORIZA TERHADAP PERTUMBUHAN TANAMAN JAGUNG (Zea Mays. L)

JURNAL ILMIAH AGRINECA ◽

10.36728/afp.v21i1.1320 ◽

2021 ◽

Vol 21 (1) ◽

pp. 62-68

Author(s):

Wiyono ◽

Setya Fikrie Afifuddin ◽

Setie Harieni ◽

Daryanti

Keyword(s):

Zea Mays ◽

Sea Level ◽

Soil Type ◽

Zea Mays L ◽

Block Design ◽

Plant Roots ◽

Inorganic Fertilizers ◽

Urea Fertilizer ◽

Randomized Block Design ◽

Maize Plants

The efficiency of inorganic fertilizers can also be done by using mycorrhizal biofertilizers. Efforts to increase corn growth need to be done by using inorganic fertilizers and biological fertilizers. This study aims to determine the effect of urea and mycorrhizae doses on the growth of maize (Zea mays. L). The research was conducted in Gejugan Village, Andong District, Boyolali Regency, an altitude of 154 m above sea level with grumusol soil type. This study used a completely randomized block design (RAKL) with two treatment factors, namely the first factor urea fertilizer dosage consisting of 4 levels, namely N0 = 0 kg / ha, N1 = 100 kg / ha, N2 = 200 kg / ha, N3 = 300 kg. / ha, and mycorrhizae consists of 3 levels, namely M0 = 0 g / plant, M1 = 5 g / plant, M2 = 10 g / plant. with 3 repetitions. The results of this study indicated that the dose of urea fertilizer affected the growth of maize, while the mycorrhizal dose did not affect the growth of maize except for the length of the plant roots. The effect of urea dose interaction with mycorrhizae only affected the root length growth of maize. The best growth of maize plants after being given a dose of urea as much as 100 kg/da and mycorrhizal biofertilizer 10 g / plant with the longest roots (40.44 cm)

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Spray volume, dose and time of day of glyphosate application in the control of Urochloa brizantha

Enero-Abril 2021 - Bioagro ◽

10.51372/bioagro333.1 ◽

2021 ◽

Vol 33 (3) ◽

pp. 151-160

Author(s):

Hugo M. Fialho e Moraes ◽

Lino Ferreira ◽

Wendel de Souza ◽

Rodrigo Magalhães Faria ◽

Marco Moreira de Freitas ◽

...

Keyword(s):

Leaf Area Index ◽

Dry Matter ◽

Block Design ◽

Time Of Day ◽

Area Index ◽

Time Of Application ◽

Randomized Block Design ◽

Spray Volume ◽

Urochloa Brizantha ◽

Different Doses

In order to optimize machinery use, the application of herbicides has been performed at different times of the day and night. Therefore, knowledge about the pesticide that will be used and how the spray volume and time of application affect the effectiveness of the product is very important. Thus, the objective of this work was to study the influence of spray volume and different time of application on the control of Urochloa brizantha by different doses of glyphosate. The treatments were arranged in a 5 x 3 x 2 factorial scheme in a randomized block design with four replications. Five doses of glyphosate (0; 1080; 1440; 1800 and 2160 g∙ha-1∙a.e.), three times of application (morning, afternoon and evening) and two spray volumes (50 and 100 L·ha-1) were evaluated. A control assessment was performed at 21 days after application, in addition to the accumulation of dry matter and the leaf area index on the regrowth. A satisfactory control of the grass was obtained for applications performed in the morning and afternoon, without interference of the volume applied and the doses tested. Evening application reduces the effectiveness of glyphosate in Urochloa brizantha burndown.

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