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1.
J Environ Qual ; 52(5): 1024-1036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533339

RESUMO

Vineyard soils can be contaminated by copper (Cu) due to successive applications of fungicides and organic fertilizers. Soil remediation can be addressed by altering soil properties or selecting efficient Cu-extracting cover crops tolerant to Cu toxicity. Our objectives were to synthesize the Cu-extracting efficiency by plant species tested in Brazil, classify them according to Cu resistance to toxicity, and assess the effect of soil properties on attenuating Cu toxicity. We retrieved results from 41 species and cultivars, totaling 565 observations. Freshly added Cu varied between 50 and 600 mg Cu kg-1 of soil across studies. The partition of Cu removal between the above- and below-ground portions was scaled as a logistic variable to facilitate data synthesis. The data were analyzed using the Adaboost machine learning model. Model accuracy (predicted vs. actual values) reached R2  = 0.862 after relating species, cultivar, Cu addition, clay, SOM, pH, soil test P, and Cu as features to predict the logistic target variable. Tissue Cu concentration varied between 7 and 105 mg Cu kg-1 in the shoot and between 73 and 1340 mg Cu kg-1 in the roots. Among soil properties, organic matter and soil test Cu most influenced the accuracy of the model. Phaseolus vulgaris, Brassica juncea, Ricinus communis, Hordeum vulgare, Sorghum vulgare, Cajanus cajan, Solanum lycopersicum, and Crotolaria spectabilis were the most efficient Cu-extracting cover crops, as shown by positive values of the logistic variable (shoot removal > root removal). Those Cu-tolerant plants showed differential capacity to extract Cu in the long run.


Assuntos
Poluentes do Solo , Biodegradação Ambiental , Fazendas , Brasil , Poluentes do Solo/análise , Cobre/análise , Solo/química , Produtos Agrícolas
2.
Plant Physiol Biochem ; 128: 89-98, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29772492

RESUMO

High copper (Cu) soil contents, due to the continuous vineyard application of Cu fungicides throughout the years, may impair the growth of the shoot and modify the structure of the root system. The current study aimed to investigate the threshold levels of available Cu in the soil causing toxicity effects in young grapevine plants of 'Red Niagara' cultivated in clay soils. Grapevine plantlets were cultivated in pots containing vineyard devoted soils with increasing contents of available Cu (25, 80, 100 and 165 mg kg-1), for 53 days. Photosynthesis and transpiration rates, and the quantum yield of photosystem II (Fv/Fm) were evaluated during the cultivation period. At the end of the experiment, the plant nutrient and leaf chlorophyll were determined, along with the anatomical analysis of the root system structure and plant dry matter determination. Higher levels of available Cu in the soil increased the apoplastic, symplastic and total fraction of the metal in the roots, reducing the other nutrients, especially in the shoots. Photosynthesis, transpiration rates and Fv/Fm were also reduced. Higher levels of Cu led to anatomical changes in the roots, that increased diameter, number of layers in the cortex, vascular cylinder and total root areas. It also resulted in reduced dry matter production by grapevines.


Assuntos
Cobre/metabolismo , Fazendas , Complexo de Proteína do Fotossistema II/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Solo/química , Vitis/metabolismo , Cobre/química , Transpiração Vegetal/fisiologia
3.
Ciênc. rural (Online) ; 48(4): e20170278, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1045093

RESUMO

ABSTRACT: Soils which are cultivated with grapevines have high available copper (Cu) content, which can be toxic to cover crops cohabiting vineyards, such as black oats. This study aimed to assess the effect of liming in reducing Cu toxicity in black oats grown in sandy soils. Samples of a Typic Hapludalf were collected at 0-20cm, dried and subjected to the addition of Cu (0 to 50Mg kg-1) and limestone (0, 1.5, and 3.0Mg ha-1). The soil was placed in a rhizobox and black oats were grown for 30 days. We assessed root and shoot dry matter production, copper (Cu), calcium (Ca) and magnesium (Mg) contents in the tissues; Cu content in the root symplast and apoplast, as well as Cu, carbon and pH values in the rhizosphere and bulk soil. Liming reduced Cu toxicity in black oats. Cu was preferentially accumulated in the roots, mostly in the apoplast, which may be the result of a plant tolerance mechanism to prevent the transport of Cu to the shoots.


RESUMO: Solos cultivados com videiras possuem alto teor de cobre (Cu) disponível, que pode ser tóxico às plantas de cobertura do solo que coabitam vinhedos, como a aveia preta. O estudo objetivou avaliar o efeito da calagem na redução da toxidez por Cu em plantas de aveia preta cultivadas em solo arenoso. Amostras de um Argissolo Vermelho foram coletadas na camada de 0-20cm, secas e submetidas à adição de duas doses de Cu (0 e 50Mg kg-1) e três de calcário (0, 1,5 e 3,0Mg ha-1). O solo foi acondicionado em rhizobox e submetido ao cultivo de aveia preta durante 30 dias. Avaliaram-se a produção de matéria seca das raízes e da parte aérea, o teor de cobre (Cu), cálcio (Ca) e magnésio (Mg) nos tecidos; o teor de Cu no simplasto e apoplasto das raízes, e os teores de Cu, de carbono e valores de pH no solo rizosférico e não rizosférico. A aplicação de calcário reduziu a toxidez por Cu na aveia preta. O Cu foi preferencialmente acumulado nas raízes, especialmente no apoplasto, o que pode ser resultado de mecanismo de tolerância das plantas para evitar o transporte de parte do elemento para a parte aérea.

4.
Ciênc. rural (Online) ; 48(5): e20160895, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-1045124

RESUMO

ABSTRACT: Weed management in apple orchards (Malus domestica) can affect the leaching of nitrogen (N) in soil. The study aimed to evaluate the potential leaching of N forms in soil of an apple orchard with different weed management treatments. The experiment was conducted in an apple orchard implanted in 2008. In October 2011, 80 plants were selected and the following treatments were implemented: no weed management (NM), desiccation of weeds on the tree row with herbicide use (DR) and mechanical mowing of weeds on the tree row (MR). Yield was evaluated in the 2011/2012, 2012/2013 and 2013/2014 crop seasons. In May 2012 porous cup lysimeters were installed in the NM, DR and MR treatments. In the solution collected at 0.20m, NH4 +-N and NO3 --N were analyzed sixteen times and mineral N concentration was calculated. The highest concentrations of NO3 --N and mineral N occurred in soil solution with DR, which increases availability of the nutrient to apple trees, but also enhances the potential losses. Weed management and N flow in the solution did not affect apple yield.


RESUMO: O manejo de plantas espontâneas em pomares de macieira (Malus domestica) pode afetar a lixiviação de nitrogênio (N) do solo. O trabalho objetivou avaliar a lixiviação de formas de N em solo sob pomar de macieiras com diferentes manejos de plantas espontâneas. O experimento foi conduzido em um pomar de macieira implantado em 2008. Em outubro de 2011, foram selecionadas 80 plantas e implantados os tratamentos: sem manejo das plantas espontâneas (SM); dessecamento das plantas espontâneas na linha de plantio com uso de herbicidas (DL) e roçada mecânica das plantas espontâneas na linha de plantio (RL). Nas safras 2011/2012, 2012/2013 e 2013/2014 foi avaliada a produtividade. Em maio de 2012 foram instalados lisímetros com cápsula porosa nos tratamentos SM, DL e RL; e na solução coletada a 0,20m em dezesseis épocas foram analisados NH4 +-N e NO3 --N, e calculado o teor de N-mineral. Os maiores teores de NO3 --N e mineral-N ocorreram na solução no solo com DL, o que aumenta a disponibilidade do nutriente às macieiras, mas também potencializa as perdas. O manejo de plantas espontâneas e o fluxo de N na solução não afetaram a produtividade de maçã.

5.
Braz J Microbiol ; 46(4): 1045-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26691462

RESUMO

High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.


Assuntos
Cobre/metabolismo , Fungos/crescimento & desenvolvimento , Micorrizas/metabolismo , Poluentes do Solo/metabolismo , Vitis/microbiologia , Fungos/metabolismo , Micorrizas/crescimento & desenvolvimento , Fósforo/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Vitis/crescimento & desenvolvimento , Vitis/metabolismo
6.
Braz. j. microbiol ; 46(4): 1045-1052, Oct.-Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-769662

RESUMO

Abstract High copper (Cu) levels in uprooted old vineyard soils may cause toxicity in transplanted young vines, although such toxicity may be reduced by inoculating plants with arbuscular mycorrhizal fungi (AMF). The objective of this study was to evaluate the effects of AMF on the plant growth, chlorophyll contents, mycorrhizal colonization, and Cu and phosphorus (P) absorption in young vines cultivated in a vineyard soil contaminated by Cu. Commercial vineyard soil with high Cu levels was placed in plastic tubes and transplanted with young vines, which were inoculated with six AMF species (Dentiscutata heterogama, Gigaspora gigantea, Acaulospora morrowiae, A. colombiana, Rhizophagus clarus, R. irregularis) and a control treatment on randomized blocks with 12 replicates. After 130 days, the mycorrhizal colonization, root and shoot dry matter (DM), height increment, P and Cu absorption, and chlorophyll contents were evaluated. The height increment, shoot DM and chlorophyll contents were not promoted by AMF, although the root DM was increased by R. clarus and R. irregularis, which had the greatest mycorrhizal colonization and P uptake. AMF increased Cu absorption but decreased its transport to shoots. Thus, AMF species, particularly R. clarus and R. irregularis, contribute to the establishment of young vines exposed to high Cu levels.


Assuntos
Cobre/crescimento & desenvolvimento , Cobre/metabolismo , Cobre/microbiologia , Fungos/crescimento & desenvolvimento , Fungos/metabolismo , Fungos/microbiologia , Micorrizas/crescimento & desenvolvimento , Micorrizas/metabolismo , Micorrizas/microbiologia , Fósforo/crescimento & desenvolvimento , Fósforo/metabolismo , Fósforo/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Brotos de Planta/microbiologia , Poluentes do Solo/crescimento & desenvolvimento , Poluentes do Solo/metabolismo , Poluentes do Solo/microbiologia , Vitis/crescimento & desenvolvimento , Vitis/metabolismo , Vitis/microbiologia
7.
Plant Physiol Biochem ; 96: 270-80, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26318144

RESUMO

Frequent applications of copper (Cu)-based fungicides on vines causes the accumulation of this metal in vineyard soils, which can cause toxicity in young vines. However, liming may reduce these toxic effects. The present study aimed to evaluate the effects of Cu toxicity on the root anatomy of young vines and the alleviation of Cu toxicity by lime applications to contaminated sandy soil. The treatments consisted of the addition of lime (0.0, 1.5 and 3.0 Mg ha(-1)) and two Cu concentrations (0 and 50 mg kg(-1)) to Typic Hapludalf soil. Young vines 'Niágara Branca' (Vitis labrusca L.) were obtained by micropropagation and cultivated for 70 days. The young vines grown with Cu and without liming presented a disorganized root structure; reduced root cap size; increased diameter (47%), cortex area (128%), vascular cylinder area (93%), and number of cortical layers and cells containing phenolic compounds (132%); and reduced root (41%), stem (44%) and leaf dry mass (21%) and height increase (55%). Moreover, Cu exposure reduced Ca concentrations (13%) and increased Cu concentrations (371%) in the roots. Liming, primarily with the highest tested dose, increased the soil pH (from 4.4 to 5.4-6.1), decreased the Cu concentration in the soil (extracted by CaCl2), increased the calcium (Ca) and magnesium (Mg) uptake by plants, prevented root anatomical changes and benefited young vine growth in soil with higher Cu concentrations.


Assuntos
Cobre/toxicidade , Raízes de Plantas/fisiologia , Vitis/fisiologia
8.
Ciênc. rural ; 45(4): 651-657, 04/2015. tab, graf
Artigo em Português | LILACS | ID: lil-742815

RESUMO

A aplicação de composto orgânico no solo pode incrementar a produção de pêssego, porém parte do N pode ser perdido por lixiviação e volatilização. O trabalho objetivou avaliar o estado nutricional das plantas, a produção de pêssego, a lixiviação de formas de N no solo e a volatilização de N-NH3 em um pomar de pessegueiro com a adição de composto orgânico produzido a partir de resíduos de agroindústrias de suco, resíduos de abatedouro de aves e serragem. O pomar foi implantado em 2009 e, em julho de 2010, 2011 e 2012, foram aplicados 0, 3, 6, 12 e 24L de composto por m2 e avaliaram-se os teores totais de nutrientes nas folhas e a produção. Em 2012, usando lisímetros instalados a 20 e a 40cm de profundidade, avaliaram-se as formas de N lixiviadas na solução percolada nos tratamentos 0 e 24L de composto. Usando câmeras coletoras, foi avaliada a volatilização de N-NH3 em todos os tratamentos até 478h depois da deposição do composto no solo. A aplicação de composto na superfície do solo incrementou o teor de K e N nas folhas completas, aumentando a produção de frutos. A aplicação de composto no florescimento aumentou a concentração de nitrato na solução do solo, somente na profundidade de 20cm. A emissão de amônia aumentou com o incremento da dose de composto aplicado, especialmente e nos períodos de maior temperatura.


The application of organic compost to the soil can increase the production of peach, although part of the N may be lost by leaching and volatilization. The aim of this study was to evaluate the nutritional status, yield of peaches, leaching of N forms and volatilization of NH3-N in a peach orchard with the addition of compost produced from agroindustrial juice waste, poultry slaughterhouse residues and sawdust. The orchard was established in 2009, and in july 2010, 2011 and 2012 the quantities of 0, 3, 6, 12 and 24L of organic compost per m2 were applied on a peach orchard and the total nutrient content in leaves and production was evaluated. In 2012, using lysimeters installed at 20 and 40cm deep in the soil, it was measured the forms of N in the solution in the treatments of 0 and 24L of compost. The volatilization of NH3-N was assessed in all the treatments up to 478h after compost application on the soil. The application of compost on the soil surface increased the content of K and N in whole leaves, increasing fruit production. The compost application at flowering increased the concentration of nitrate in the soil solution at a depth of only 20cm. The ammonia emission increased especially with the augmenting dose of compost applied, and in periods of higher temperature.

9.
Ciênc. rural ; 44(12): 2164-2170, 12/2014. tab, graf
Artigo em Português | LILACS | ID: lil-729819

RESUMO

A aplicação de fontes de nitrogênio (N) em pomar de macieira pode incrementar o teor do nutriente no solo ao longo do ciclo, afetar o estado nutricional e a produção, mas parte do N pode ser perdido por lixiviação. O trabalho objetivou avaliar o teor de N total em folhas, a produção e o fluxo de N no solo e na solução, em um pomar de macieira com a aplicação de distintas fontes de N, em um experimento em Urubici (SC). Plantas foram selecionadas, receberam a aplicação de ureia (U), ureia peletizada (UP) e cama sobreposta de suínos (CS); além de um tratamento sem adubação (SA). Nas safras 2011/2012 e 2012/2013 foram analisados teores de N em folhas completas e mensurados o crescimento das plantas e a produção de frutos. Foram coletadas amostras de solo e de solução, e analisados os teores de N-NH4 + e N-NO3 - ao longo da segunda safra. Aplicações de U, UP e CS aumentaram o rendimento da macieira no segundo ano, mas o teor de N em folhas não foi afetado nas duas safras. A aplicação de N afetou o fluxo de formas do nutriente no solo e na solução ao longo do ciclo da cultura, com pequenos incrementos nos teores do solo e da solução em períodos próximos à aplicação das diferentes fontes de N.


The application of nitrogen (N), from different sources, in apple orchard can increase soil N content, affecting the plant's nutritional status and yield, but part of the N can be lost by leaching. With the aim of assessing plant nutritional status and yield, and N flow in the soil and solution an experiment was carried out in in an apple orchard in Southern Brazil, applying different N source. Selected plants received the following treatments: application of urea, pelletized urea or pig deep litter, besides a control without fertilization. In the 2011/2012 and 2012/2013 crop seasons, N contents in whole leaves were analyzed and plant growth and fruit yield parameters were measured. Soil and soil solution samples were collected and the NH4 +-N and NO3 --N contents were analyzed during the second crop season. Application of pig deep litter, urea and pelletized urea increased apple yield in the second crop season, with no differences among treatments in leaf total N content at any time period. The application of N to the soil affected the flow of nutrient forms in the soil and in the solution throughout the apple crop cycle, with small increases in soil and in solution contents in periods near the application of the different N sources to the soil.

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