Sebastiao Guimaraes

Federal University of Mato Grosso | UFMT · Departamento de Agronomia

Portulaca oleracea L., known as purslane, is an unconventional food plant rich in nutrients and medicinal properties, with potential for consumption and commercialization. The objective was to describe phenological stages of purslane based on BBCH (Biologische Bundesantalt, Bundessortenamt and Chemische Industrie) scale and thermal sum at different...

Seed germination is regulated by temperature and can thus be quantified by thermal models, which can predict germination occurrence in biomes and plant survival under possible climate change scenarios. The objective of this study was to quantify germination based on thermal time and survival risk of 14 species in the Brazilian Cerrado in scenarios...

O objetivo deste trabalho foi avaliar o desenvolvimento de bananeiras ‘Grand Naine’ e ‘BRS Tropical’ sob diferentes tipos de adubos orgânicos no primeiro ciclo de produção. O delineamento experimental foi em blocos casualizados com quatro repetições de quatro plantas cada. Os tratamentos constituíram-se por: esterco de bovinos, esterco de aves, efl...

Post-harvest cotton stalk control is mandatory in many cotton producing countries, and the major methods used for this practice are mechanical and chemical (glyphosate and 2,4-D as the most usual herbicides applied), or a combination of both. However, the adoption of glyphosate-resistant cotton varieties by growers have required the development of...

This study aimed to evaluate the plant growth regulator application, in different doses, on priming, with and without water restriction, in corn seeds. Evaluations were carried out in two periods (0 to 30 days of storage), with treatments consisting of seeds primed in water (0.0 MPa) and polyethylene glycol 6000 solution (-0.4 MPa), with or without...

Estudos relacionados com a biologia de plantas daninhas são importantes, pois contribuem para a adoção de estratégias de manejo racionais, aproveitando sistemas de rotação ou consorciação com culturas. Com o presente trabalho teve-se o objetivo de avaliar o efeito da presença de palha na emergência de plântulas de Conyza canadensis e C. bonariensis...

This study aimed to evaluated different methodologies and water potentials for priming of maize seeds, in order to increase vigor. The experiment was carried out following a completely randomized design, in a factorial scheme 4x3+1, with four water potentials (0.0, -0.4, -0.8 and -1.2 MPa), three priming methods (immersion in non-aerated solution,...

This study aimed to evaluated different methodologies and water potentials for priming of maize seeds, in order to increase vigor. The experiment was carried out following a completely randomized design, in a factorial scheme 4×3+1, with four water potentials (0.0,−0.4,−0.8 and −1.2 MPa), three priming methods (immersion in non-aerated solution, im...

Conyza canadensis e C. bonariensis infestam lavouras de ciclo anual e perene em todo mundo. Fatores ambientais, como a presença de compostos químicos específicos podem interferir significativamente na germinação de suas sementes, fato importante para entender a dinâmica de infestação dessas espécies. Este trabalho teve como objetivo avaliar o efeit...

Amaranthus palmeri, a principal planta daninha dos algodoais nos Estados Unidos, foi identificada na região do núcleo algodoeiro Centro--Norte do estado de Mato Grosso, em áreas normalmente cultivadas com rotação das culturas de algodão, soja e milho. Essa espécie é exótica e esse é o primeiro relato de sua ocorrência no Brasil. No ano de 2014, em...

Considerações gerais na destruição química da soqueira: • Nas áreas da propriedade em que a colheita é realizada em épocas em que ainda estão ocorrendo algumas precipitações (geralmente até 15 de agosto), o melhor tem sido roçar e aplicar imediatamente os herbicidas, e fazer monitoramento constante da área para a avaliação dos escapes. Dificilmente...

RESUMO O objetivo deste trabalho foi avaliar a influência de adubos orgânicos na população microbiana e sua atividade no solo. Para tal, foram coletadas, em dois períodos, amostras de solo na Fazenda Experimental da Universidade Federal de Mato Grosso, no Município de Santo Antônio de Leverger. O delineamento experimental adotado foi em blocos casu...

A restrição hídrica tem sido utilizada nos meios de cultura com o objetivo de inibir ou retardar a germinação das sementes e permitir maior exposição dessas a um inóculo, desde que o potencial osmótico do meio restrinja a germinação das sementes e não prejudique o desenvolvimento das colônias do patógeno. Visando a inoculação de Fusarium verticilli...

http://dx.doi.org/10.5902/198050988458Qualea grandiflora Mart. ocorre em matas de galeria e cerrado, sendo conhecida popularmente como pau-terra. Com o objetivo de obter informações sobre a propagação reprodutiva dessa espécie foi estudado o efeito da temperatura sobre a germinabilidade das sementes. As temperaturas utilizadas foram: 15, 20, 25, 30...

Qualea grandiflora Mart. occurs in riverine forests and in 'cerrado' areas, popularly known as 'pauterra'. With the purpose of obtaining information about the reproductive spread of this species, it was studied the effect of temperature on seed germination capability. The temperatures used were: 15, 20, 25, 30, 35 and 40°C. The seeds were sown on p...

O vigor das sementes pode influenciar a emergência, o desempenho e produtividade das plantas, dependendo de cada espécie e de fatores ambientais. Dessa forma, um dos principais desafios das pesquisas com sementes é averiguar a influência do potencial fisiológico das sementes sobre o ciclo das plantas. O objetivo deste trabalho foi avaliar o efeito...

Conyza canadensis and C. bonariensis are weeds of increasing importance in world. Soil salinity is regarded as one of the major abiotic stresses, causing damage to plant metabolism and deleterious effects in many physiological processes of plants, including germination of species of agronomic interest such as weeds. In order to increase knowledge a...

The weed species Conyza canadensis and C. bonariensis have been increasingly reported, given their capacity to develop under the no-tillage system (NTS). Light is necessary for germination of several weeds, and is considered a factor of seed dormancy break. Seed germination in NTS is affected by light wave length filtering by straw, which can direc...

Buva é o nome popular de plantas daninhas do gênero Conyza pertencentes à família Asteraceae e representadas no Brasil particularmente por duas espécies Conyza canadensis e Conyza bonariensis. Ambas infestam áreas de cultivo agrícola, além de campos, áreas de pastagem e áreas não-cultivadas. Suas características biológicas como a produção de grande...

Horseweed (Conyza canadensis and C. bonariensis) is a weed of increasing importance in Brazil. These species occur in different regions of the world and are important weeds in perennial and annual crops under no tillage, minimum tillage and horticultural areas. In this work, we studied the effect of constant temperatures on germination of both spec...

Seed germination can be greatly influenced by environmental conditions, which affects the establishment of floristic communities. The weeds, although they had features as hardiness and its ability to germinate seeds under environmental stress conditions, may experience the direct effect of the presence of toxic elements in the substrate. Aluminum,...

The objective of this study was to evaluate the germinability of Chloris barbata (L.) Sw. seeds as a function of water availability. The treatments were organized according to a 7 × 2 factorial arrangement, with seven water potential values: 0.0; -0.2; -0.4; -0.6; -0.8; -1.0, or -1.2 MPa, by two dispersal units: spikelets or caryopses. A completely...

Conyza canadensis and C. bonariensis are weeds of increasing importance in world. Soil salinity is regarded as one of the major abiotic stresses, causing damage to plant metabolism and deleterious effects in many physiological processes of plants, including germination of species of agronomic interest such as weeds. In order to increase knowledge a...

Recent reports show Conyza canadensis and C. bonariensis as important weeds of the agricultural system. The great ecological adaptability of these species to conservationist soil management systems and the increased selection pressure caused by intense herbicide use may contribute to selection of resistant biotypes. Understanding the factors factor...

Temperature fluctuations associated with high rainfall and the oscillating relative humidity of the air during the pre-harvest stages of seed maturation may result in losses in physical and physiological quality and also in seed health. Pre-harvest desiccant application helps to reduces seed exposure to unfavourable climate conditions and reduce se...

Temperature fluctuations associated with high rainfall and the oscillating relative humidity of the air during the pre-harvest stages of seed maturation may result in losses in physical and physiological quality and also in seed health. Pre-harvest desiccant application helps to reduces seed exposure to unfavourable climate conditions and reduce se...

The chemical management of weeds in reforestation areas has been carried out increasingly due to its speed, economy and control. Glyphosate has been widely used in forest ecosystems, due to the absence of a residual effect in the soil. In order to increase its efficiency, it is often mixed with 2,4-D. However, both herbicides are not selective for...

O objetivo deste trabalho foi avaliar o efeito do armazenamento em areia úmida e do pré-tratamento com ácido giberélico na germinação das sementes de castanheira-do-pará. Foram realizados dois experimentos em delineamento experimental de blocos ao acaso, com cinco repetições; o primeiro em viveiro, em arranjo fatorial 4x2, com quatro períodos de ar...

The objective of this work was to evaluate the effects of storage in moist sand and treatment with gibberellic acid on Brazil nut seed germination. Two experiments were carried out in a randomized block design, with five replicates. The first one was done in the nursery, in a factorial 4x2 arrangement, with four storage periods in moist sand (0, 90...

There are few herbicides available to the coffee grower for the post-emergency application in plants of coffee in formation. The present work was accomplished with the objective of evaluating the coffee plant seedlings phytointoxication to herbicides application in post-emergency. The herbicides bentazon, oxyfluorfen, haloxyfop-methyl, imazethapyr,...

Ruta graveolens L., also known as rue, is from the south of Europe, cultivated in Brazil and other countries as a medicinal plant greatly used in religious rituals. Since germination is essential for the seed to generate a vigorous plant of high productive potential, this work aimed to evaluate the germinative response of rue seeds under different...

Chaptalia nutans is species whose medicinal value has been studied thoroughly, and aspects regarding seed germination are important to define better propagation practices. The objective of the present study was to evaluate the germination response of C. nutans seeds to conditions of light and temperature, as well as osmotic and saline stresses and...

The knowledge of basic aspects of the biology of weeds can contribute significantly to the development of strategies for their handling. Emilia sonchifolia is a weed spread throughout the Brazilian territory; it presents moderate aggressiveness being found in agricultural and urban areas. This work aimed to evaluate germination of E. sonchifolia se...

Com o objetivo estudar a relação existente entre o banco de sementes e o posterior estabelecimento da flora emergente de plantas daninhas, sob sistema de semeadura direta e convencional, realizou-se uma pesquisa no município de Pedra Preta-MT. O banco de sementes e a flora emergente foram avaliados, em cada sistema de cultivo, em 50 células contígu...

O agronegócio do algodão apresenta-se, no Brasil, como uma atividade de grande importância para a economia nacional, ocupando posição de destaque no processo produtivo do Estado do Mato Grosso. Para que a cultura possa expressar o máximo potencial produtivo, é necessária a adoção de técnicas de manejo e práticas agronômicas, visando o controle das...

Este trabalho teve por objetivos avaliar o efeito da temperatura e do estresse hídrico na germinação das sementes e na formação de plântulas normais de Amburana acreana. Foram realizados dois ensaios. No primeiro, as sementes foram colocadas para germinar nas temperaturas de 20, 25, 30, 35 e 40°C. No segundo, as sementes foram dispostas em substrat...

O trabalho teve por objetivo avaliar a eficiência dos testes de deterioração controlada, de envelhecimento acelerado tradicional e modificado para avaliação do potencial fisiológico de sementes de algodoeiro, representadas por oito lotes da variedade CD 406. Para o teste de deterioração controlada, o grau de umidade das sementes foi ajustado para 1...

Cotonicultores do cerrado, receosos da ocorrência de fitotoxicidade, têm utilizado o herbicida alachlor em dosagens inferiores à mínima recomendada na bula, com baixo efeito residual. Com o objetivo de estudar fatores relacionados à seletividade do alachlor ao algodoeiro, foram realizados dois experimentos. No primeiro, em caixas de germinação com...

The knowledge of the biology and of the ecology of weeds precede the elaboration of agronomic strategies for weed control, reducing the costs of the productive process. Certain plants, in addition to other biological characteristics of importance, have their germination capacity influenced by abiotic factors such as temperature and brightness. With...

O agronegócio do algodão apresenta-se, no Brasil, como uma atividade de grande importância para a economia nacional, ocupando posição de destaque no processo produtivo do Estado do Mato Grosso. Para que a cultura possa expressar o máximo potencial produtivo, é necessária a adoção de técnicas de manejo e práticas agronômicas, visando o controle das...

Brazilian savanna cotton growers in fear of phytotoxicity have been using the herbicide alachlor below the minimum dosage recommended by the manufacturer, with low residual activity. Two experiments were carried out to study factors related to alachlor selectivity to cotton. The first assay used germination boxes with sand substrate to study two al...

A study was carried out in Pedra Petra-MT aiming to study the relation between seed bank and posterior aboveground weed in annual crop fields under no-till and tillage systems. The seed bank and weed flora were assessed in fifty contiguous 1 m2 cells, under both cultivation systems. The seed bank was determined from soil samples from 4% of the area...

This work aimed to evaluate the effects of reduced rates of simulated drift of glyphosate on cotton crop using different cultivars and development levels. The assay was carried out in Alta Floresta, MT. The reduced doses of glyphosate were 0,180 and 360 g a.e. ha-1. The cultivars ITA-90 and BRS-Facual were treated at the four and 10 leaf stages and...

This work aimed to evaluate the influence of cotton plant treatment using reduced rates of glyphosate, simulating drift, on the quality of the seeds produced. The plants of the ITA-90 and BRS-Facual cultivars were treated at two different development stages (4 and 10 leaves) with glyphosate in the doses of 0; 180 and 360 g ha-1 ea. Cotton crop yiel...

The response of nine cotton cultivars economically important in the state of Mato Grosso was evaluated in relation to the toxicity caused by reduced rates of glyphosate. The cotton cultivars used were Fabrika, Makina, ITA-90, FM 986, FM 966, Delta Opal, BRS Facual, Antares and Coodetec 407. The plants were cultivated in plastic pots filled with soi...

Hyptis cana, commonly known as hortelã-do-campo, hortelã-do- cerrado and horteläzinha, is a species with medicinal use; the objective of this study was to determine its optimum, minimum and maximum temperatures for seed germination and normal seedling development. The inflorescences were collected from native populations in two distinct areas in th...

A manutenção da viabilidade das sementes é muito influenciada pelas condições de armazenamento. No caso das plantas daninhas, essa informação pode servir como suporte para a realização de outras pesquisas e também ajudar na compreensão da dinâmica das infestações. Neste trabalho, a viabilidade das sementes da planta daninha erva-de-touro (Tridax pr...

Seed viability is strongly influenced by storage conditions. In weeds, this information may serve as support for other research works and help to understand infestation dynamics as well. This work, conducted at Universidade Federal de Lavras, was carried out to evaluate the viability of coat button (Tridax procumbens) seeds stored in cold chamber (...

Os solos agrícolas possuem banco de sementes de plantas daninhas cuja quantidade varia de dezenas a centenas de milhões de sementes por hectare, as quais são dotadas de mecanismos para detectar o tempo e o local apropriado para a germinação. A profundidade no solo em que uma semente é capaz de germinar e produzir plântula é variável entre as espéci...

Agricultural soils may contain weed seedbanks of hundreds of millions of weed seeds per hectare, which have mechanisms to detect the appropriate time and place for germination. The soil depth in which a seed is capable of germinating varies among species, presenting ecological and agronomic importance. With the objective of studying Tridax procumbe...

Abstract. Mulching as an alternative to weed management is already consolidated, but the ways of using this varies depending on the material used as such, the target weed, as well as according to the disposal of the material in the soil profile. This study aimed to evaluate the effect of organic material from plant and animal waste in the emergence...

The aim of this study was to evaluate the effect of constant temperatures on the seed germination of Tridax procumbens, a weed of increasing importance in Brazil. Germination was carried out with 4 replicates of 100 seeds (achenes) from 3 different samples. Seeds were placed between two layers of blotting-paper, soaked in distilled water inside clo...

Resumo Estudos relacionados com a biologia de plantas daninhas são importantes, pois contribuem para a adoção de estratégias de manejo racionais, aproveitando sistemas de rotação ou consorciação com culturas. O presente trabalho teve como objetivo avaliar o efeito da presença de palha na emergência de plântulas de Conyza canadensis e C. bonariensis...

A retirada da vegetaçao natural de para utilização de -. uma area espec~es cultivadas, rompe o equilíbrio existente, facilitando a introdução e a prol! feração das plantas daninhas, as quais possuem grande capacidade de adaptação em locais desbravados. Nas regiões sob vegetaçao de cerrado, em geral, implanta-se a cultura ., gram~ neas, atinge grand...

1 UNIVAG, (65) 9922-2262; alcavenaghi@uol.com.br; 2 UFMT; sheep@ufmt.br; 3 IHARABRAS DO BRASIL; cappellesso@ihara.com.br Resumo O objetivo deste trabalho foi avaliar o controle de plantas daninhas em pós-emergência na cultura do algodoeiro transgênico resistente ao glyphosate, utilizando-se a mistura dos herbicidas glyphosate e pyrithiobac. O exper...