ABSTRACT
RESUMEN Perú generó 8.215.355 t de residuos sólidos municipales en el 2021; de este, 57,64 % corresponde a residuos orgánicos (RO) y 61,28 % son dispuestos en rellenos sanitarios con múltiples deficiencias de gestión, lo que exige buscar alternativas para tratar de manera segura los RO. Frente a esta situación, el compostaje permite la biotransformación, la reducción y la obtención de biofertilizantes, que se pueden aplicar como sustrato o enmienda. El objetivo de la investigación fue evaluar indicadores de procesamiento y calidad de compost derivado de residuos sólidos orgánicos urbanos, en Leoncio Prado, región Huánuco, Perú. Se evaluaron los tipos de residuos, basados en la normativa peruana para caracterización de residuos, los indicadores del proceso (temperatura y pH), la caracterización fisicoquímica y calidad en base a las normas internacionales. Los resultados muestran diferencia significativa para pH, nitrógeno, calcio, potasio, cobre y zinc; contrariamente, la materia orgánica, el % de cenizas, la conductividad eléctrica, el sodio y el fósforo no mostraron diferencias, siendo lo más destacado los altos niveles de pH, además, la calidad del compost es de "Clase B", según la norma chilena 2880. Los compost producidos son de calidad media y se recomienda su uso como sustrato o enmienda en la agricultura, previo tratamiento para corregir los altos niveles de pH.
ABSTRACT Peru generated 8,215,355 t of municipal solid waste in 2021, of which 57.64% corresponds to organic waste (OW) and 61.28% is disposed of in landfills with multiple management deficiencies, which makes it necessary to seek alternatives to safely treat OW. In view of this situation, composting allows biotransformation, reduction and obtaining biofertilizers that can be applied as a substrate or amendment. The objective of the research was to evaluate the processing indicators and quality of compost derived from urban organic solid waste in Leoncio Prado, Huánuco-Peru. Waste types were evaluated based on Peruvian regulations for waste characterization, process indicators (temperature and pH), physicochemical characterization and quality based on international standards. The results show significant differences for pH, nitrogen, calcium, potassium, copper and zinc; on the contrary, organic matter, % ash, electrical conductivity, sodium and phosphorus showed no differences, the most outstanding being the high pH levels, and the quality of the compost is "Class B" according to Chilean standard 2880. The compost produced is of medium quality and is recommended for use as a substrate or amendment in agriculture after treatment to correct the high pH levels.
ABSTRACT
Poultry waste has been used as fertilizer to avoid soil degradation caused by the long-term application of chemical fertilizer. However, few studies have evaluated field conditions where livestock wastes have been used for extended periods of time. In this study, physicochemical parameters, metabarcoding of the 16S rRNA gene, and ecotoxicity indexes were used for the characterization of chicken manure and poultry litter to examine the effect of their application to agricultural soils for 10 years. Poultry wastes showed high concentrations of nutrients and increased electrical conductivity leading to phytotoxic effects on seeds. The bacterial communities were dominated by typical members of the gastrointestinal tract, noting the presence of pathogenic bacteria. Soils subjected to poultry manure applications showed statistically higher values of total and extractable phosphorous, increasing the risk of eutrophication. Moreover, while the soil bacterial community remained dominated by the ones related to the biogeochemical cycles of nutrients and plant growth promotion, losses of alpha diversity were observed on treated soils. Altogether, our work would contribute to understand the effects of common local agricultural practices and support the adoption of the waste treatment process in compliance with environmental sustainability guidelines.
Subject(s)
Poultry , Soil , Animals , Soil/chemistry , Manure , Fertilizers , RNA, Ribosomal, 16S/genetics , Bacteria/genetics , Genetic VariationABSTRACT
The impact of pig slurry (PS) application on the structural dynamics of humic substances (HS) and on the mobility of Cu, Zn, Ni, and Pb in a dystrophic Red Nitosol planted with winter forage grasses was evaluated. After four PS applications, the humic acids (HA) and fulvic acids (FA) were characterized by spectroscopy techniques allied to chemometrics methods. The metals contents in soil, in HS and in the tissues of plant were quantified. PS application increases the total organic carbon, especially the nonhumic carbon, which contribute to increase FA content. The carbon in FA and HA increases with the highest PS dose applied, especially aliphatic structures in FA and aromatic structures in HA. The amount of Pb and Cu in FA and HA increases respectively, as well as Cu, Zn, Ni, and Pb bioavailable. PS applications increase the biomass production in grasses and the metals content accumulated in the tissues. Our study shows that the PS application modifies the structure of SOM, incorporating fragments, and modifying its dynamics, which regulates the dynamics and the accumulation of metals in soils and plants. The association of metals with soluble structures seems to inactivate their toxicity and does not affect plant growth.
Subject(s)
Metals, Heavy , Soil Pollutants , Swine , Animals , Soil/chemistry , Lead , Metals, Heavy/chemistry , Humic Substances/analysis , Soil Pollutants/analysis , Carbon/chemistry , PlantsABSTRACT
This study aimed to characterize the effect of amending soils with biochars derived from soybean residues, sugarcane bagasse, and wood chips on the sorption-desorption of indaziflam and indaziflam-triazinediamine (FDAT), indaziflam-triazine-indanone (ITI), and indaziflam-carboxylic acid (ICA) metabolites applied to soils from three Midwestern U.S. states, a silt loam and a silty clay loam. Biochars produced from different feedstock were used as soil amendments and compared with raw feedstock. Sorption-desorption experiments of indaziflam and its three metabolites were performed using the batch equilibration method and analyzed for 14C activity by liquid scintillation counting (radiometric technique). In all soils, the use of organic amendments promoted greater sorption and less desorption of indaziflam and ITI. The addition of biochar to soils promoted greater sorption of the four tested chemical products compared with the corresponding raw materials. Among the biochars, grape wood chips showed greater potential in sorb indaziflam and ITI. In general, none of the biochars affected the sorption and desorption of FDAT and ICA. Characterization of biochar to be used as a soil amendment (immobilizer) is highly recommended prior to field addition to optimize the sorption process and to prevent increased soil and water contamination of indaziflam and its metabolites following biochar addition.
Subject(s)
Herbicides , Soil Pollutants , Adsorption , Charcoal , Herbicides/analysis , Indenes , Soil , Soil Pollutants/analysis , TriazinesABSTRACT
The sludges derived from the leachate treatment (LS) represent an important environmental and operational problem in the landfill management. On the other hand, they can be utilized as an alternative source of nutrients and organic matter. The main objective of this work was to evaluate the reuse of the LS of a sanitary landfill in Santa Fe city - Argentina, as an organic amendment for the development of Nicotiana alata L. plants. Different doses of LS were applied to a soil mixture for potted seedling growth. The response surface methodology was applied, using a one-factor design. Once the phenological stage of flowering began, the plants were harvested. Physiological and biochemical determinations were made in order to evaluate the effects of the different amendments. Application of LS notably improved growth parameters such as stem height, leaf area and dry matter. Additionally, the content of proteins and photosynthetic pigments was enhanced. Through the multiple regression statistical analyses, the relationship between the response variables and the sludge content was established. The multivariate optimization analysis yielded 53% as the optimal sludge content. Our results indicate that this sludge, in appropriate doses, can be used as an organic amendment for the revegetation of sanitary landfills.
Subject(s)
Sewage , Water Pollutants, Chemical , Argentina , Nutrients , Nicotiana , Water Pollutants, Chemical/analysisABSTRACT
Disturbances in soil can cause short-term soil changes, consequently changes in microbial community what may result in long-lasting ecological effects. Here, we evaluate how multiple pulse disturbances effect the dynamics and resilience of fungal community, and the co-occurrence of fungal and bacterial communities in a 389â¯days field experiment. We used soil under sugarcane cultivation as soil ecosystem model, and organic residue (vinasse - by-product of sugarcane ethanol production) combined or not with inorganic (organic residue applied 30â¯days before or together with mineral N fertilizer) amendments as disturbances. Application of organic residue alone as a single disturbance or 30â¯days prior to a second disturbance with mineral N resulted in similar changes in the fungal community. The simultaneous application of organic and mineral N as a single pulse disturbance had the greatest impact on the fungal community. Organic amendment increased the abundance of saprotrophs, fungal species capable of denitrification, and fungi described to have copiotrophic and oligotrophic lifestyles. Furthermore, the changes in the fungal community were not correlated with the changes in the bacterial community. The fungal community was neither resistant nor resilient to organic and inorganic disturbances over the one-year sampling period. Our findings provide insights on the immediate and delayed responses of the fungal community over one year to disturbance by organic and inorganic amendments.
Subject(s)
Mycobiome , Fertilizers/analysis , Fungi , Soil , Soil MicrobiologyABSTRACT
Lead-polluted agricultural soils are a serious problem for food safety, with organic amendment being a promising mitigation method from the environmental perspective. Therefore, the purpose of this study was to evaluate lead availability and the effectiveness of the application of compost of biosolid with wood shavings and yard trimmings in contaminated soils. The physicochemical (Pb distribution, organic matter, pH, electric conductivity, cation exchange capacity, nitrogen, phosphorus, carbon, carbonates, exchangeable cations, sodium) and biological parameters (the microbial activity obtained by fluorescein diacetate hydrolysis) in Pb-polluted and non-polluted agricultural soils were evaluated after the addition of biosolid with wood shavings and yard trimming compost. Topsoils (lead-polluted and control) were collected in the vicinity of a former battery-recycling plant, amended with compost (0%, 5%, and 10%), and incubated in controlled conditions for 118 days. The results showed that lead availability decreased significantly, and the nutritional quality of the soils increased in the soils amended with 10% of compost. Taken together, the results of the present study indicated that compost amendment could be an effective method for mitigating the negative effects of lead in agricultural soils.
Subject(s)
Biosolids/analysis , Composting , Lead/analysis , Soil Pollutants/analysis , Soil/chemistry , Wood/chemistry , Agriculture , Argentina , RecyclingABSTRACT
Developing countries currently face challenges related to the management and disposal of biosolids that result from wastewater treatment. One of the most important issues they must deal with involves the maximum level of pathogens permitted and the effect they may have on the environment and human health once they are used for agricultural purposes. In order to learn about the risk generated by these kinds of practices, we assessed the behavior of indicators of fecal contamination in grasses used to feed dairy cattle. The study area was divided into two plots: an experimental plot in which diluted biosolids were applied and a control plot without the application of biosolids. We collected samples from soil, grass, surface water and groundwater and analyzed the presence of fecal coliforms, Salmonella spp., somatic phages and helminth eggs. Experimental and control plots showed a decrease in the concentration of bacterial indicators assessed in soil, and low concentrations in surface water, groundwater and grass. Concentrations of viral and parasite indicators tend to decrease more slowly. Our results show that this way of biosolid management allows a better use of its benefits as an organic amendment by lowering the sanitary risk due to the presence of pathogens.
Los países en vías de desarrollo enfrentan el reto de la gestión y disposición de los biosólidos resultantes del tratamiento de aguas residuales. Uno de los más importantes temas está relacionado con el máximo nivel de patógenos permitidos y el efecto que puedan causar en el ambiente y en la salud humana cuando este material es utilizado para uso agrícola. Con el objetivo de conocer el riesgo generado por este tipo de prácticas, evaluamos el comportamiento de los indicadores de contaminación fecal en un cultivo de pasto usado como alimento para ganado lechero. El área de estudio se dividió en dos parcelas: una experimental en la cual se aplicaron lodos diluidos y otra control sin aplicación de biosólidos. Se recolectaron muestras de suelo, pasto, aguas superficiales y subterráneas y se analizó la presencia de coliformes fecales, Salmonella spp., fagos somáticos y huevos de helminto. Las concentraciones encontradas tanto en la parcela experimental como en la control, presentan disminución de los indicadores bacterianos evaluados en suelo y bajas concentraciones en el agua superficial, subterránea y en pasto; mientras que los indicadores virales y parasitarios tienden a disminuir más lentamente. Los resultados muestran como este tipo de gestión del biosólido permite aprovechar sus beneficios como enmienda orgánica, disminuyendo el riesgo sanitario generado por la presencia de patógenos.
Os países em vias de desenvolvimento enfrentam o desafio da gestão e disposição dos biosólidos resultantes do tratamento de águas residuais. Um dos mais importantes temas se relaciona com o nivel máximo de patogénicos permitidos e o efeito que podem causar no ambiente e na saúde humana, quando este material é utilizado para o uso agrícola. Com o objetivo de conhecer o risco gerado por este tipo de praticas, avaliamos o comportamiento dos indicadores de contaminação fecal num cultivo de pasto utilizado como alimento para o gado leiteiro. A área de estudo dividiu-se em duas partes: uma experimental, na qual se aplicaram lodos diluídos e outra sem aplicação de biosólidos. Se recolheram amostras de solo, pasto, águas superficiais e superficiais e subterráneas, e se analisou a presença de coliformes fecais, Salmonella spp., fagos somáticos e ovos de helminto. As concentrações encontradas tanto na parte experimental como na de controlo, apresentam diminuição dos indicadores bacterianos avaliados no solo e baixas concentrações na água superficial, subterránea e em pasto; enquanto os indicadores virais e parasitários tendem a diminuir mais lentamente. Os resultados mostram como este tipo de gestão de biosólidos permite aproveitar os benefícios como emenda orgánica, diminuindo o risco sanitário gerado pela presença de patogénicos.
ABSTRACT
A aplicação conjunta de agentes de controle biológico e matéria orgânica pode potencializar o controle do nematoide das galhas em hortaliças. Desta forma, o objetivo deste estudo foi avaliar o efeito da aplicação de Pochonia chlamydosporia (Hypocreales: Clavicipitaceae) (PC) e esterco bovino na redução populacional de Meloidogyne javanica (Tylenchida: Heteroderidae) em tomateiro. Os tratamentos foram constituídos da incorporação ao solo de 20g de canjiquinha colonizada pelo fungo (PC), 20g de canjiquinha não-colonizada (CNC), 70g de esterco bovino + 20g de canjiquinha colonizada (EBPC) e apenas 70g de esterco bovino (EB). Ao solo de cada vaso foi adicionado o respectivo tratamento e 5.000 ovos de M. javanica, seguido pelo transplantio das mudas. A incorporação ao solo de EBPC, seguido de EB, aumentou a biomassa da parte aérea e das raízes de tomateiros. A maior redução no número de galhas e de ovos de M. javanica foi observada após a aplicação de EB, seguido por EBPC. Não houve diferença significativa na aplicação apenas do fungo em relação à testemunha considerando a avaliação do número de galhas e de ovos.
Concomitant application of biological control agents and organic amendment can enhance the control of the root-knot nematode on vegetables. Thus, the objective of this study was to evaluate the effect of the application of Pochonia chlamydosporia (Hypocreales: Clavicipitaceae) (PC) and cow manure on the reduction of the Meloidogyne javanica (Tylenchida: Heteroderidae) on tomato. The treatments were: 20 g of milled corn colonized by the fungus (PC), 20 g of non-colonized milled corn (NCMC), 70g of cow manure + 20g of PC-colonized milled corn (CMPC) and 70g of cow manure alone (CM). Into the soil of each pot was added the respective treatment and 5,000 eggs of M. incognita and M. javanica, separately, followed by the transplanting of the seedlings. Soil amendment with CMPC, followed by CM, increased the tomato aboveground and root system biomass. Highest reduction on the number of galls and eggs was observed after soil amendment with CM, followed by CMPC. No significant reduction on the number of galls and eggs was observed by the application of PC.
Subject(s)
Plant Tumors , Tylenchoidea , Solanum lycopersicum , Hypocreales , Manure , Nematoda , Pest Control, Biological , Organic MatterABSTRACT
Se investigó el efecto del follaje del "huacatay" Tagetes minuta sobre la nodulación radicular producida por el nematodo Meloidogyne incognita que parasita el "pimiento páprika" Capsicum annuum cultivado en invernadero, con la finalidad de obtener una alternativa de control de este nematodo. Se utilizaron tres grupos experimentales y un testigo, con 12 macetas cada uno, las cuales contenían suelo y arena estériles (1:1). A este substrato se adicionó el follaje de T. minuta al 20, 35 y 50% (v/v) según grupo experimental, y el testigo no recibió esta enmienda. En cada maceta se sembró una plántula de C. annuum, y a la semana postsiembra se inoculó 5000 huevos de M. incognita. A las ocho semanas, se evaluaron los nódulos en sus raíces. Todas las plantas presentaron nódulos; aunque, en aquellas de los grupos experimentales el número de éstos fue menor que en las plantas testigo, con diferencia estadística significativa (p 0,05). Se concluye que el follaje de T. minuta adicionado como enmienda orgánica al 20, 35 y 50% al suelo de cultivo de plantas de C. annuum limita la nodulación radicular ocasionada por M. incognita. Lo cual sugiere su uso potencial en el control de este nematodo
The effect of the foliage of Tagetes minuta "huacatay" on Meloidogyne incognita root-galling on Capsicum annuum "paprika pepper" cultured in a greenhouse was researched, to obtain a control strategy for this nematode. Three experimental groups and one control with 12 pots each were used, which contained sterilized soil and sand (1:1). To this substrate was added cut foliage of T. minuta at 20, 35 and 50% (v/v) according to the experimental group, and the control group remained without this amendment. In each pot a seedling of C. annuum was sown, and one week post-seeding was inoculated with 5000 eggs of M. incognita. Eight weeks later the root galling was evaluated. All the plants had root galling; although the number of galls in plants of the experimental groups was less than those in the control group with statistical significant difference (p 0.05). It is concluded that the foliage of T. minuta added as organic amendment at 20, 35 and 50% to the culture soil for C. annuum plants limits the M. incognita root galling. That suggests its potential use in the control of this nematode
ABSTRACT
Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm²) or ground (1mm sieve) dry leaves of assa-peixe (Vernonia polyanthes), lemon-grass (Cymbopogon citratus), eucalyptus (Eucalyptus citriodora), castor (Ricinus communis), mango (Mangifera indica) or neem (Azadirachta indica) for the control Meloidogyne javanica. Into the soil (Yellow red oxisol) of each pot were added leaves (5g kg-1 of soil) and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61 percent). The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69 percent), evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica.
Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm²) ou trituradas (peneira de 1mm) de assa-peixe (Vernonia polyanthes), capim-limão (Cymbopogon citratus), eucalipto (Eucalyptus citriodora), mamona (Ricinus communis), manga (Mangifera indica) ou nim (Azadirachta indica) para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo), foram adicionadas folhas (5g kg-1 de solo) e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e de ovos foram avaliados 60 dias após o transplantio. As folhas picadas de nenhuma planta reduziram o número de galhas e de ovos. Entretanto, as folhas de todas as plantas estudadas reduziram o número de galhas quando foram incorporadas ao solo na forma de pó e a máxima supressão foi obtida com as folhas de nim (61 por cento). A adição ao solo de folhas trituradas de mamona, nim, eucalipto e capim-cidreira reduziu o número de ovos, com redução máxima após aplicação de folhas de mamona (69 por cento), indicando que esses materiais orgânicos podem ser uma alternativa de controle de M. javanica em tomateiro. Novos estudos devem ser realizados em condições de campo para confirmar o potencial desses materiais orgânicos no controle de M. javanica.
ABSTRACT
Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm²) or ground (1mm sieve) dry leaves of assa-peixe (Vernonia polyanthes), lemon-grass (Cymbopogon citratus), eucalyptus (Eucalyptus citriodora), castor (Ricinus communis), mango (Mangifera indica) or neem (Azadirachta indica) for the control Meloidogyne javanica. Into the soil (Yellow red oxisol) of each pot were added leaves (5g kg-1 of soil) and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61%). The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69%), evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica.
Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm²) ou trituradas (peneira de 1mm) de assa-peixe (Vernonia polyanthes), capim-limão (Cymbopogon citratus), eucalipto (Eucalyptus citriodora), mamona (Ricinus communis), manga (Mangifera indica) ou nim (Azadirachta indica) para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo), foram adicionadas folhas (5g kg-1 de solo) e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e de ovos foram avaliados 60 dias após o transplantio. As folhas picadas de nenhuma planta reduziram o número de galhas e de ovos. Entretanto, as folhas de todas as plantas estudadas reduziram o número de galhas quando foram incorporadas ao solo na forma de pó e a máxima supressão foi obtida com as folhas de nim (61%). A adição ao solo de folhas trituradas de mamona, nim, eucalipto e capim-cidreira reduziu o número de ovos, com redução máxima após aplicação de folhas de mamona (69%), indicando que esses materiais orgânicos podem ser uma alternativa de controle de M. javanica em tomateiro. Novos estudos devem ser realizados em condições de campo para confirmar o potencial desses materiais orgânicos no controle de M. javanica.
ABSTRACT
Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm²) or ground (1mm sieve) dry leaves of assa-peixe (Vernonia polyanthes), lemon-grass (Cymbopogon citratus), eucalyptus (Eucalyptus citriodora), castor (Ricinus communis), mango (Mangifera indica) or neem (Azadirachta indica) for the control Meloidogyne javanica. Into the soil (Yellow red oxisol) of each pot were added leaves (5g kg-1 of soil) and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61%). The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69%), evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica.
Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm²) ou trituradas (peneira de 1mm) de assa-peixe (Vernonia polyanthes), capim-limão (Cymbopogon citratus), eucalipto (Eucalyptus citriodora), mamona (Ricinus communis), manga (Mangifera indica) ou nim (Azadirachta indica) para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo), foram adicionadas folhas (5g kg-1 de solo) e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e de ovos foram avaliados 60 dias após o transplantio. As folhas picadas de nenhuma planta reduziram o número de galhas e de ovos. Entretanto, as folhas de todas as plantas estudadas reduziram o número de galhas quando foram incorporadas ao solo na forma de pó e a máxima supressão foi obtida com as folhas de nim (61%). A adição ao solo de folhas trituradas de mamona, nim, eucalipto e capim-cidreira reduziu o número de ovos, com redução máxima após aplicação de folhas de mamona (69%), indicando que esses materiais orgânicos podem ser uma alternativa de controle de M. javanica em tomateiro. Novos estudos devem ser realizados em condições de campo para confirmar o potencial desses materiais orgânicos no controle de M. javanica.
ABSTRACT
The aim of this work was to evaluate the use of green manure nitrogen (Crotalaria juncea L.)-15N and urea-15N, in conjugated and separate fertilization. The experiment was carried out in pots with 5kg of a Rhodic Hapludox (sample collected in 0-20cm depth), using wheat (Triticum aestivum L.), cv. IAC-24. The completely randomized design was used with 5 treatments and 4 replicates: T1 - urea-15N (45mg kg-1 of N-urea); T2 - Crotalaria juncea-15N (100mg kg-1 of N-crotalária); T3 - Crotalaria juncea-14N (100mg kg-1 of N-crotalária) and urea-15N (45mg.kg-1 of N-urea); T4 - urea-14N (45mg.kg-1 of N-urea) and Crotalaria juncea-15N (100mg.kg-1 of N-crotalária); T5 - treatment control (without source with N). The harvest of plants was realized 50 days after emergency (DAE), at flowering stage, separating the shoot of the root, being also sampled the soil of each pot. The parameter evaluated were the dry weight, height of plants, content of N and 15N abundance, being calculated the recovery of nitrogen from the sources. The N-urea recovery in wheat was larger, compared to N-crotalária that stayed immobilized in the soil. In the soil-plant system, the N-crotalária recovery was higher then N-urea. The soil fertilization with urea conjugated with crotalária or applied separately resulted in larger dry weight and content of N in wheat. The use of Crotalaria juncea as green manure provided conservation of nitrogen, promoting larger recovery of the nutrient in the soil-plant system.
O objetivo deste trabalho foi avaliar o aproveitamento do nitrogênio de adubo verde (Crotalaria juncea L.)-15N e da uréia-15N, em fertilização conjugada e separada. O experimento foi conduzido em vasos contendo 5kg de um Latossolo Vermelho distrófico típico (amostra colhida na profundidade de 0-20cm), utilizando trigo (Triticum aestivum L.), cultivar IAC-24. O delineamento inteiramente casualizado foi usado com 5 tratamentos e 4 repetições: T1 - uréia-15N (45mg kg-1 de N-uréia); T2 - Crotalaria juncea-15N (100mg kg-1de N-crotalária); T3 - Crotalaria juncea-14N (100mg kg-1de N-crotalária) e uréia-15N (45mg kg-1 de N-uréia); T4 - uréia-14N (45mg kg-1 de N-uréia) e Crotalaria juncea-15N (100mg kg-1de N-crotalária); T5 - tratamento controle (sem adição de fontes de N). A colheita das plantas de trigo foi realizada aos 50 dias após a emergência (DAE), no estádio de florescimento, separando-se a parte aérea do sistema radicular, sendo também amostrado o solo de cada vaso. Os parâmetro avaliados foram a massa de material seco, altura de plantas, conteúdo de N e abundância de 15N, sendo calculada a recuperação do nitrogênio proveniente das fontes. A recuperação do N-uréia nas plantas de trigo foi maior que o N-crotalária, que permaneceu imobilizado no solo. No sistema solo-planta, a recuperação do N-crotalária foi igual ao N-uréia. A fertilização do solo com uréia conjugada à crotalária ou aplicada separadamente, resultou em maior massa de material seco e conteúdo de N-total nas plantas de trigo. A utilização da Crotalaria juncea como fonte de nitrogênio pode ser uma alternativa para ampliar a conservação do nutriente no sistema solo-planta.
ABSTRACT
The aim of this work was to evaluate the use of green manure nitrogen (Crotalaria juncea L.)-15N and urea-15N, in conjugated and separate fertilization. The experiment was carried out in pots with 5kg of a Rhodic Hapludox (sample collected in 0-20cm depth), using wheat (Triticum aestivum L.), cv. IAC-24. The completely randomized design was used with 5 treatments and 4 replicates: T1 - urea-15N (45mg kg-1 of N-urea); T2 - Crotalaria juncea-15N (100mg kg-1 of N-crotalária); T3 - Crotalaria juncea-14N (100mg kg-1 of N-crotalária) and urea-15N (45mg.kg-1 of N-urea); T4 - urea-14N (45mg.kg-1 of N-urea) and Crotalaria juncea-15N (100mg.kg-1 of N-crotalária); T5 - treatment control (without source with N). The harvest of plants was realized 50 days after emergency (DAE), at flowering stage, separating the shoot of the root, being also sampled the soil of each pot. The parameter evaluated were the dry weight, height of plants, content of N and 15N abundance, being calculated the recovery of nitrogen from the sources. The N-urea recovery in wheat was larger, compared to N-crotalária that stayed immobilized in the soil. In the soil-plant system, the N-crotalária recovery was higher then N-urea. The soil fertilization with urea conjugated with crotalária or applied separately resulted in larger dry weight and content of N in wheat. The use of Crotalaria juncea as green manure provided conservation of nitrogen, promoting larger recovery of the nutrient in the soil-plant system.
O objetivo deste trabalho foi avaliar o aproveitamento do nitrogênio de adubo verde (Crotalaria juncea L.)-15N e da uréia-15N, em fertilização conjugada e separada. O experimento foi conduzido em vasos contendo 5kg de um Latossolo Vermelho distrófico típico (amostra colhida na profundidade de 0-20cm), utilizando trigo (Triticum aestivum L.), cultivar IAC-24. O delineamento inteiramente casualizado foi usado com 5 tratamentos e 4 repetições: T1 - uréia-15N (45mg kg-1 de N-uréia); T2 - Crotalaria juncea-15N (100mg kg-1de N-crotalária); T3 - Crotalaria juncea-14N (100mg kg-1de N-crotalária) e uréia-15N (45mg kg-1 de N-uréia); T4 - uréia-14N (45mg kg-1 de N-uréia) e Crotalaria juncea-15N (100mg kg-1de N-crotalária); T5 - tratamento controle (sem adição de fontes de N). A colheita das plantas de trigo foi realizada aos 50 dias após a emergência (DAE), no estádio de florescimento, separando-se a parte aérea do sistema radicular, sendo também amostrado o solo de cada vaso. Os parâmetro avaliados foram a massa de material seco, altura de plantas, conteúdo de N e abundância de 15N, sendo calculada a recuperação do nitrogênio proveniente das fontes. A recuperação do N-uréia nas plantas de trigo foi maior que o N-crotalária, que permaneceu imobilizado no solo. No sistema solo-planta, a recuperação do N-crotalária foi igual ao N-uréia. A fertilização do solo com uréia conjugada à crotalária ou aplicada separadamente, resultou em maior massa de material seco e conteúdo de N-total nas plantas de trigo. A utilização da Crotalaria juncea como fonte de nitrogênio pode ser uma alternativa para ampliar a conservação do nutriente no sistema solo-planta.