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1.
Ci. Rural ; 47(12): 1-8, dez. 2017. tab, graf
Artículo en Inglés | VETINDEX | ID: vti-21416

RESUMEN

The objective of this study was to evaluate the silvicultural performance of four forest species introduced in a setting for integrated livestock forest (ILF) in a pasture in Lavras, Minas Gerais, Brazil. The species included were the Australian red cedar (seminal and clonal), African mahogany, teak, and guanandi. A split plot scheme with a randomized complete block design comprising four replicates and 48 plants per plot, was used in the following arrangement: (3(3x2) +7x2) m. The evaluation times (12, 18, 31, 36, and 43 months after planting) corresponded to the subplots. Performances of all four species were evaluated on the basis of their survival rate, height (H) and diameter at breast height (DBH). Based on the performance of the species with regard to these parameters, the clonal Australian red cedar showed a greater growth in DBH and height in the ILF setting as compared to the other species, which indicates it to be a suitable species for the region of Lavras, MG as long as its survival control occurs in the implantation phase.(AU)


Objetivou-se com este trabalho avaliar o desempenho silvicultural de quatro espécies florestais introduzidas em arranjo para Integração Pecuária Floresta (IPF) sobre pastagem, em Lavras, Minas Gerais. As espécies estudadas foram o cedro australiano (seminal e clonal), mogno africano, teca e guanandi. Utilizou-se o delineamento de blocos casualizados completos, em esquema de parcelas subdivididas no tempo, com quatro repetições e 48 plantas por parcela no arranjo (3(3x2)+7x2)m. As subparcelas corresponderam às épocas de avaliações (12, 18, 31, 36 e 43 meses pós-plantio). Os desempenhos das espécies foram avaliados por meio dos parâmetros de sobrevivência, diâmetro à altura do peito e altura. Com base no desempenho das espécies, o cedro australiano clonal apresentou maior crescimento em DAP e altura no arranjo para IPF sendo esta a espécie indicada para Lavras/MG, desde que na fase de implantação ocorra o controle da sobrevivência.(AU)


Asunto(s)
Especies Introducidas , Crianza de Animales Domésticos , Agricultura Forestal
2.
Braz. j. microbiol ; Braz. j. microbiol;47(12): 1-8, dez. 2017. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1469629

RESUMEN

The objective of this study was to evaluate the silvicultural performance of four forest species introduced in a setting for integrated livestock forest (ILF) in a pasture in Lavras, Minas Gerais, Brazil. The species included were the Australian red cedar (seminal and clonal), African mahogany, teak, and guanandi. A split plot scheme with a randomized complete block design comprising four replicates and 48 plants per plot, was used in the following arrangement: (3(3x2) +7x2) m. The evaluation times (12, 18, 31, 36, and 43 months after planting) corresponded to the subplots. Performances of all four species were evaluated on the basis of their survival rate, height (H) and diameter at breast height (DBH). Based on the performance of the species with regard to these parameters, the clonal Australian red cedar showed a greater growth in DBH and height in the ILF setting as compared to the other species, which indicates it to be a suitable species for the region of Lavras, MG as long as its survival control occurs in the implantation phase.


Objetivou-se com este trabalho avaliar o desempenho silvicultural de quatro espécies florestais introduzidas em arranjo para Integração Pecuária Floresta (IPF) sobre pastagem, em Lavras, Minas Gerais. As espécies estudadas foram o cedro australiano (seminal e clonal), mogno africano, teca e guanandi. Utilizou-se o delineamento de blocos casualizados completos, em esquema de parcelas subdivididas no tempo, com quatro repetições e 48 plantas por parcela no arranjo (3(3x2)+7x2)m. As subparcelas corresponderam às épocas de avaliações (12, 18, 31, 36 e 43 meses pós-plantio). Os desempenhos das espécies foram avaliados por meio dos parâmetros de sobrevivência, diâmetro à altura do peito e altura. Com base no desempenho das espécies, o cedro australiano clonal apresentou maior crescimento em DAP e altura no arranjo para IPF sendo esta a espécie indicada para Lavras/MG, desde que na fase de implantação ocorra o controle da sobrevivência.


Asunto(s)
Agricultura Forestal , Crianza de Animales Domésticos , Especies Introducidas
3.
Ciênc. rural (Online) ; 47(12): e20161106, Dec. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1044924

RESUMEN

ABSTRACT: The objective of this study was to evaluate the silvicultural performance of four forest species introduced in a setting for integrated livestock forest (ILF) in a pasture in Lavras, Minas Gerais, Brazil. The species included were the Australian red cedar (seminal and clonal), African mahogany, teak, and guanandi. A split plot scheme with a randomized complete block design comprising four replicates and 48 plants per plot, was used in the following arrangement: (3(3x2) +7x2) m. The evaluation times (12, 18, 31, 36, and 43 months after planting) corresponded to the subplots. Performances of all four species were evaluated on the basis of their survival rate, height (H) and diameter at breast height (DBH). Based on the performance of the species with regard to these parameters, the clonal Australian red cedar showed a greater growth in DBH and height in the ILF setting as compared to the other species, which indicates it to be a suitable species for the region of Lavras, MG as long as its survival control occurs in the implantation phase.


RESUMO: Objetivou-se com este trabalho avaliar o desempenho silvicultural de quatro espécies florestais introduzidas em arranjo para Integração Pecuária Floresta (IPF) sobre pastagem, em Lavras, Minas Gerais. As espécies estudadas foram o cedro australiano (seminal e clonal), mogno africano, teca e guanandi. Utilizou-se o delineamento de blocos casualizados completos, em esquema de parcelas subdivididas no tempo, com quatro repetições e 48 plantas por parcela no arranjo (3(3x2)+7x2)m. As subparcelas corresponderam às épocas de avaliações (12, 18, 31, 36 e 43 meses pós-plantio). Os desempenhos das espécies foram avaliados por meio dos parâmetros de sobrevivência, diâmetro à altura do peito e altura. Com base no desempenho das espécies, o cedro australiano clonal apresentou maior crescimento em DAP e altura no arranjo para IPF sendo esta a espécie indicada para Lavras/MG, desde que na fase de implantação ocorra o controle da sobrevivência.

4.
An. acad. bras. ciênc ; 89(4): 2581-2595, Oct.-Dec. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886839

RESUMEN

ABSTRACT This paper presents a paleoenvironmental reconstruction from palynological analyses of a sedimentary core of Holocene age, drilled at municipality of Garopaba (Santa Catarina), Southern Brazil. A total of 46 samples was collected for palynological analyses in the 450 cm-long core PCSC-3, as also three samples for radiocarbon dating and granulometric analyses. The palynological content includes 84 taxa related to pollen grains of angiosperms (38) and gimnosperm (3), spores of pteridophyta (16) and bryophyta (2), spores of fungi (8), algae (3), acritarchs (3), dinoflagellate cysts (2) and microforaminiferal linings (1). Three specimens of acritarchs are described and illustrated in detail. Three palynological phases were defined based on changes in assemblages: Phase I, Phase II and Phase III. The Phase I is characterized as a lagoonal paleoenvironment with marine influence from the beginning of the sedimentation (5390 cal yr BP), based on occurrences of acritarchs, dinoflagellate cysts and microforaminiferal linings. The Phase II (3032 yr BP until 858 cal yr BP) also is characterized by a lagoonal paleoenvironment, however, presented decrease in percentage of marine elements and increase in freshwater algae record, suggesting less marine influence in the lagoonal body. In Phase III (last 856 years), underwater sedimentation prevailed, under swamp-like conditions.

5.
An Acad Bras Cienc ; 89(4): 2581-2595, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29069134

RESUMEN

This paper presents a paleoenvironmental reconstruction from palynological analyses of a sedimentary core of Holocene age, drilled at municipality of Garopaba (Santa Catarina), Southern Brazil. A total of 46 samples was collected for palynological analyses in the 450 cm-long core PCSC-3, as also three samples for radiocarbon dating and granulometric analyses. The palynological content includes 84 taxa related to pollen grains of angiosperms (38) and gimnosperm (3), spores of pteridophyta (16) and bryophyta (2), spores of fungi (8), algae (3), acritarchs (3), dinoflagellate cysts (2) and microforaminiferal linings (1). Three specimens of acritarchs are described and illustrated in detail. Three palynological phases were defined based on changes in assemblages: Phase I, Phase II and Phase III. The Phase I is characterized as a lagoonal paleoenvironment with marine influence from the beginning of the sedimentation (5390 cal yr BP), based on occurrences of acritarchs, dinoflagellate cysts and microforaminiferal linings. The Phase II (3032 yr BP until 858 cal yr BP) also is characterized by a lagoonal paleoenvironment, however, presented decrease in percentage of marine elements and increase in freshwater algae record, suggesting less marine influence in the lagoonal body. In Phase III (last 856 years), underwater sedimentation prevailed, under swamp-like conditions.

6.
Ci. Rural ; 46(6): 1032-1037, June 2016. tab
Artículo en Inglés | VETINDEX | ID: vti-29574

RESUMEN

This study aimed to evaluate the growth of rubber tree clones ( Hevea brasiliensis (Willd.exA.Juss.) Müll. Arg.) in the Northwest region of Minas Gerais, Brazil. Randomized blocks, constituted of three treatments (rubber tree clones) and four repetitions were used, and evaluated as plots subdivided in time. Subplots represent the evaluations carried out at the ages 62, 77, 87, 99, 113 and 128 months after planting. It was evaluated survival, stem circumference and total plant height. Current annual increment and average annual increment of circumference and also the number of trees fit for rubber tapping were calculated. Results obtained indicate that clones GT 1, IAN 2880, IAC 15, RRIM 600, PB 235 and IAN 3156 have potential to establish under local edaphoclimatic conditions. Increase in plant height and stem circumference throughout the evaluation period makes it evident that the clones have different growing paces in the studied region. Clones GT 1, IAN 3087, IAN 3156 and PR 255 had larger stalk circumference at 128 months, and PR 255 was the only one fit for rubber tapping at the age of 128 months after planting.(AU)


Objetivou-se no presente estudo avaliar o comportamento e o crescimento de clones de seringueira ( Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.) introduzidos na região noroeste do estado de Minas Gerais. O delineamento utilizado foi o de blocos casualizados, constituído por 12 clones de seringueira, quatro repetições, avaliadas em esquema de parcelas subdivididas no tempo: aos 62, 77, 87, 99, 113 e 128 meses após o plantio. Foram avaliadas a sobrevivência, a circunferência e altura total da planta. A partir dessas informações, foram calculados o incremento corrente anual e o incremento médio anual da variável circunferência, e o número de árvores aptas à sangria. Os resultados obtidos indicaram que os clones GT 1, IAN 2880, IAC 15, RRIM 600, PB 235 e IAN 3156 apresentam potencial de estabelecimento às condições edafoclimáticas da região. O crescimento em altura e circunferência ao longo do período de avaliação evidencia que os clones de seringueira apresentam diferentes ritmos de crescimento na região de estudo. Os clones GT 1, IAN 3087, IAN 3156 e PR 255 foram os que apresentaram maior circunferência de caule aos 128 meses, sendo o clone PR 255 o único clone apto à sangria aos 128 meses de idade após o plantio.(AU)


Asunto(s)
Células Clonales , Hevea/crecimiento & desarrollo , Hevea/fisiología , Desarrollo de la Planta
7.
Ciênc. rural ; Ciênc. rural (Online);46(6): 1032-1037, June 2016. tab
Artículo en Inglés | LILACS | ID: lil-779840

RESUMEN

ABSTRACT: This study aimed to evaluate the growth of rubber tree clones ( Hevea brasiliensis (Willd.exA.Juss.) Müll. Arg.) in the Northwest region of Minas Gerais, Brazil. Randomized blocks, constituted of three treatments (rubber tree clones) and four repetitions were used, and evaluated as plots subdivided in time. Subplots represent the evaluations carried out at the ages 62, 77, 87, 99, 113 and 128 months after planting. It was evaluated survival, stem circumference and total plant height. Current annual increment and average annual increment of circumference and also the number of trees fit for rubber tapping were calculated. Results obtained indicate that clones GT 1, IAN 2880, IAC 15, RRIM 600, PB 235 and IAN 3156 have potential to establish under local edaphoclimatic conditions. Increase in plant height and stem circumference throughout the evaluation period makes it evident that the clones have different growing paces in the studied region. Clones GT 1, IAN 3087, IAN 3156 and PR 255 had larger stalk circumference at 128 months, and PR 255 was the only one fit for rubber tapping at the age of 128 months after planting.


RESUMO: Objetivou-se no presente estudo avaliar o comportamento e o crescimento de clones de seringueira ( Hevea brasiliensis (Willd. ex A. Juss.) Müll. Arg.) introduzidos na região noroeste do estado de Minas Gerais. O delineamento utilizado foi o de blocos casualizados, constituído por 12 clones de seringueira, quatro repetições, avaliadas em esquema de parcelas subdivididas no tempo: aos 62, 77, 87, 99, 113 e 128 meses após o plantio. Foram avaliadas a sobrevivência, a circunferência e altura total da planta. A partir dessas informações, foram calculados o incremento corrente anual e o incremento médio anual da variável circunferência, e o número de árvores aptas à sangria. Os resultados obtidos indicaram que os clones GT 1, IAN 2880, IAC 15, RRIM 600, PB 235 e IAN 3156 apresentam potencial de estabelecimento às condições edafoclimáticas da região. O crescimento em altura e circunferência ao longo do período de avaliação evidencia que os clones de seringueira apresentam diferentes ritmos de crescimento na região de estudo. Os clones GT 1, IAN 3087, IAN 3156 e PR 255 foram os que apresentaram maior circunferência de caule aos 128 meses, sendo o clone PR 255 o único clone apto à sangria aos 128 meses de idade após o plantio.

8.
Rev. interdisciplin. estud. exp. anim. hum. (impr.) ; 7(único): 7-14, novembro 2015. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-964813

RESUMEN

Introduction: Rutin, a flavonoid commonly found in nature, has anti-mitotic, vasoprotective, and antihyperlipidemic activity. When hydrolyzed as quercetin, it promotes inhibition of spermatozoa motility, alterations in the prostate, and in the levels of testosterone and dihydrotestosterone. Objective: This study aimed to evaluate the toxicity of rutin in Wistar rats. Methods: Animals were divided into Control (1 ml of distilled water), Treated I, II and III, respectively receiving 5, 10 and 20 mg/kg/day of rutin for seven consecutive days. When euthanasia was performed after 10, 42 and 60 days into the experiment, a laparotomy was performed and the testicles, prostate, seminal vesicles, epididymis, epididymal spermatozoa to be counted, as well as the liver, spleen and kidneys were removed. Hematological and biochemical tests were performed. Results: Hepatomegaly was observed and in the reproductive system, the weight of the epididymis was reduced, not affecting any other organ examined. Conclusion: Except by the reduction of the weight of the epididymis, which is reversible at 42 days of completion of treatment, no suggestive data of the toxicity of rutin on the reproductive system of adult rats were found.


Asunto(s)
Animales , Ratas , Rutina/toxicidad , Epidídimo , Genitales Masculinos/efectos de los fármacos , Ratas Wistar , Eutanasia Animal
9.
J Agric Food Chem ; 61(36): 8499-503, 2013 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-23947385

RESUMEN

Two of major weeds affecting cereal crops worldwide are Avena fatua L. (wild oat) and Lolium rigidum Gaud. (rigid ryegrass). Thus, development of new herbicides against these weeds is required; in line with this, benzoxazinones, their degradation products, and analogues have been shown to be important allelochemicals and natural herbicides. Despite earlier structure-activity studies demonstrating that hydrophobicity (log P) of aminophenoxazines correlates to phytotoxicity, our findings for a series of benzoxazinone derivatives do not show any relationship between phytotoxicity and log P nor with other two usual molecular descriptors. On the other hand, a quantitative structure-activity relationship (QSAR) analysis based on molecular graphs representing structural shape, atomic sizes, and colors to encode other atomic properties performed very accurately for the prediction of phytotoxicities of these compounds against wild oat and rigid ryegrass. Therefore, these QSAR models can be used to estimate the phytotoxicity of new congeners of benzoxazinone herbicides toward A. fatua L. and L. rigidum Gaud.


Asunto(s)
Benzoxazinas/química , Benzoxazinas/farmacología , Herbicidas/química , Herbicidas/farmacología , Malezas/efectos de los fármacos , Relación Estructura-Actividad Cuantitativa , Avena , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Análisis Multivariante , Poaceae/efectos de los fármacos , Control de Malezas/métodos
10.
Food Chem Toxicol ; 50(3-4): 816-22, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22198063

RESUMEN

Morus nigra L. is a plant employed as a substitute for the conventional hormonal replacement therapy. This work analyzes the estrogenic effect of M. nigra on the reproductive system and embryonic development of Wistar rats. Female rats were orally treated with M. nigra hydroalcoholic extract (MnHE) at the dose levels of 25, 50, 75, 350 and 700 mg/kg of body weight over 15 days, and continued through mating until the 14th day of gestation. Vaginal smears were performed daily and the body weight of the females was recorded at 5 days intervals. On day 15 of gestation, the females were killed and their kidneys, liver, spleen and ovaries were removed and weighed. The number of implants, resorptions, and live and dead fetuses were evaluated. Histological sections of ovaries, measurement of the height of the uterine epithelium and vaginal smears were performed to assess the estrogenic activity. The results showed that the administration of MnHE did not significantly alter the analyzed variables. Therefore, considering the experimental model used in this study, the data obtained indicate that M. nigra did not exhibit any estrogenic activity nor did exert a toxic effect on the female reproductive system and on the embryonic development of rats.


Asunto(s)
Morus/química , Extractos Vegetales/farmacología , Reproducción/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Desarrollo Embrionario/efectos de los fármacos , Estrógenos/farmacología , Femenino , Ratas , Ratas Wistar , Frotis Vaginal
11.
An. acad. bras. ciênc ; 82(3): 731-745, Sept. 2010. graf, mapas, tab
Artículo en Inglés | LILACS | ID: lil-556808

RESUMEN

A sedimentar core collected at Santo Antônio da Patrulha, Rio Grande do Sul State, southmost Brazil, was submitted to pollen analysis to provide the vegetational history of this region, and the paleoecological and paleoclimatic changes. A total of 98 taxa of palynomorphs was identified from 35 subsamples. Three radiocarbonic datings were obtained along a section of 115 cm depth, including the basal age of 4730 ± 50 yr BP. Pollen diagrams and cluster analysis were performed based on palynomorphs frequencies, demonstrating five distinct phases (SAP-I to SAP-V), which reflected different paleoecological conditions. The predominance of plants associated with grasslands in the phase SAP-I suggests warm and dry climate conditions. A gradual increasing of humidity conditions was observed mainly from the beginning of the phase SAP-III, when the vegetation set a mosaic of grasslands and Atlantic rainforest. Furthermore, the presence of some forest taxa ( Acacia-type, Daphnopsis racemosa, Erythrina-type and Parapiptadenia rigida-type), from the phase SAP-IV, is interpreted as an influence of the seasonal semideciduous forest in the study region. From the phase SAP-V (ca. 4000 yrs BP), the vegetation became similar to the modern one (extant Atlantic rainforest Biome), especially after 2000 yrs BP (calibrated age).


Um testemunho de sondagem coletado em Santo Antônio da Patrulha, Rio Grande do Sul, Brasil, foi submetido para análise polínica a fim de revelar a história vegetacional e mudanças paleoecológicas e paleoclimáticas. Um total de 98 táxons foi identificado a partir de 35 subamostras. Três datações radiocarbônicas foram obtidas ao longo de uma seção de 115 cm de profundidade, incluindo a idade basal de 4730 ± 50 anos AP. Diagramas polínicos e análises de agrupamentos foramrealizadas com base nas freqüências dos palinomorfos, demonstrando cinco fases distintas (SAP-I a SAP-V), as quais refletiram diferentes condições paleoecológicas. A predominância de plantas relacionadas à vegetação campestre na fase SAP-I sugere condições climáticas quentes e secas. Um gradual aumento nas condições de umidade foi observado principalmente no início da fase SAP-III, quando a vegetação conformou um mosaico de Campos e Floresta Atlântica. Além disso, a presença de certos táxons florestais (tipo- Acacia, Daphnopsis racemosa, tipo Erythrina e tipo Parapiptadenia rigida), a partir da fase SAP-IV, é interpretada como influência da Floresta Estacional Semidecidual na região de estudo. A partir da fase SAP-V (ca. 4000 anos AP) a vegetação tornou-se similar à moderna (atual Bioma da Floresta Atlântica), especialmente após 2000 anos AP (idade calibrada).


Asunto(s)
Sedimentos Geológicos/análisis , Polen/clasificación , Árboles/clasificación , Brasil , Clima , Paleontología
12.
An Acad Bras Cienc ; 82(3): 731-45, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21562701

RESUMEN

A sedimentar core collected at Santo Antônio da Patrulha, Rio Grande do Sul State, southmost Brazil, was submitted to pollen analysis to provide the vegetational history of this region, and the paleoecological and paleoclimatic changes. A total of 98 taxa of palynomorphs was identified from 35 subsamples. Three radiocarbonic datings were obtained along a section of 115 cm depth, including the basal age of 4730 ± 50 yr BP. Pollen diagrams and cluster analysis were performed based on palynomorphs frequencies, demonstrating five distinct phases (SAP-I to SAP-V), which reflected different paleoecological conditions. The predominance of plants associated with grasslands in the phase SAP-I suggests warm and dry climate conditions. A gradual increasing of humidity conditions was observed mainly from the beginning of the phase SAP-III, when the vegetation set a mosaic of grasslands and Atlantic rainforest. Furthermore, the presence of some forest taxa ( Acacia-type, Daphnopsis racemosa, Erythrina-type and Parapiptadenia rigida-type), from the phase SAP-IV, is interpreted as an influence of the seasonal semideciduous forest in the study region. From the phase SAP-V (ca. 4000 yrs BP), the vegetation became similar to the modern one (extant Atlantic rainforest Biome), especially after 2000 yrs BP (calibrated age).


Asunto(s)
Sedimentos Geológicos/análisis , Polen/clasificación , Árboles/clasificación , Brasil , Clima , Paleontología
13.
Ciênc. agrotec., (Impr.) ; 33(1): 105-112, jan.-fev. 2009. tab
Artículo en Portugués | LILACS | ID: lil-507959

RESUMEN

Estudos de qualidade do solo são importantes para o entendimento da interação dessa com o ecossistema como um todo. Nesse contexto, os microrganismos do solo desempenham papel fundamental para manutenção e produtividade de vários agroecossistemas. Objetivou-se, neste trabalho avaliar os atributos biológicos (carbono da biomassa microbiana, respiração basal e quociente microbiano), além do teor de carbono orgânico, possíveis indicadores das alterações na qualidade do solo impostas pelos diferentes sistemas de manejo, em relação ao cerrado nativo, em sistema agrossilvopastoril, no noroeste de Minas Gerais. Foram coletadas amostras, nas profundidades de 0-5, 5-20 e 20-40 cm, de um Latossolo Vermelho Distrófico típico (LVd), entre os municípios de Vazante e Paracatu. Os sistemas foram selecionados segundo o histórico de uso: (1) CN- cerrado nativo (testemunha); (2) EA- eucalipto + arroz (ano zero do sistema agrossilvopastoril, plantados após o desmatamento da vegetação nativa de cerrado); (3) ES-eucalipto + soja (ano um do sistema, semeadura da soja em substituição ao arroz); (4) EP- eucalipto + pastagem (ano dois do sistema, com pastagem de Brachiaria brizantha Stapf., para a engorda do gado de corte); (5) EPG- eucalipto + pastagem + gado de corte (ano três do sistema, com a introdução do gado de corte); (6) PP- pastagem plantada de Brachiaria brizantha Stapf.; e (7) EC- eucalipto no sistema convencional no espaçamento de 2,0 x 3,0 m. O carbono orgânico e o carbono da biomassa microbiana apresentaram valores mais elevados na camada superficial (0-5cm), em relação às demais, em todos os sistemas. O carbono orgânico mostrou alteração substancial em relação aos sistemas estudados e às profundidades, revelando seu potencial como indicador da qualidade do solo em termos de reflexos das modificações impostas pelo manejo. O teor de carbono da biomassa microbiana foi reduzido em todos sistemas estudados em relação ao cerrado nativo, em função da...


Soil quality studies are important for understanding its interaction with the ecosystem as a whole. In this context, the soil microorganisms play a fundamental role for the maintenance and productivity of various agricultural ecosystems. This work had the objective to evaluate the biological attributes (microbial biomass carbon, basal respiration, and microbial quotient), as well as the organic matter content, possible indicators of alterations in soil quality imposed by different management systems, in relation to native cerrado, in agricultural - forestry - pasture system, in northwest of Minas Gerais state, Brazil. Samples were collected at 0-5, 5-20, and 20-40 cm depths, from a typical Dystrophic Red Latosol (Oxisol), between Vazante and Paracatu counties. The systems were selected according to the history of use, as follows: (1) CN - native cerrado (reference); (2) EA - eucalyptus + rice (year zero of agricultural - forestry - pasture system, planted after removal of cerrado native vegetation); (3) EP - eucalyptus + soybeans (year one of system, soybeans sowing substituting rice); (4) - EP - ES - eucalyptus + pasture (year two of system, using Brachiaria Brizantha Stapf. for cattle raising); (5) - EPG - eucalyptus + pasture + cattle (year three of system, with introduction of cattle); (6) PP - pasture cultivated with Brachiaria Brizantha Stapf.; and (7) EC - eucalyptus under conventional system in 2x3m spacing. The organic carbon and the microbial biomass carbon presented higher values in the superficial layer (0 - 5 cm), in relation to the other depths, in all systems. The organic carbon showed substantial alteration in relation to the studied systems and depths assessed, revealing its potential as soil quality indicator concerning the modifications imposed by management. The microbial biomass carbon content decreased in all systems in comparison with native cerrado due to anthropic action. Along the progress of the agricultural...

14.
Ciênc. agrotec., (Impr.) ; 31(4): 1067-1074, jul.-ago. 2007. ilus, graf, tab
Artículo en Portugués | LILACS | ID: lil-461568

RESUMEN

Com o presente trabalho, objetivou-se avaliar a incidência da ferrugem e da cercosporiose do cafeeiro em diferentes sistemas de cultivo, agroflorestais e a pleno sol, através da curva de progresso dessas doenças. Utilizou-se o delineamento inteiramente casualizado, com três tratamentos e sete repetições. Os tratamentos foram compostos por cafeeiros consorciados com ingazeiro, cafeeiros consorciados com grevílea e cafeeiros cultivados convencionalmente a pleno sol. As avaliações foram realizadas mensalmente no período de abril de 2001 a março de 2003. Realizou-se o cálculo da área abaixo da curva de progresso da doença (AACPD), a qual foi submetida à análise de variância. Para a incidência da ferrugem do cafeeiro o consórcio cafeeiro x ingazeiro mostrou-se com maiores índices da doença, sendo que os tratamentos consórcio cafeeiro x grevílea e cafeeiro a pleno sol não diferiram entre si e apresentaram menores incidências da doença. Diminuição na luz solar direta e maior umidade podem ter favorecido a ferrugem no sistema cafeeiro x ingazeiro. Para a incidência de cercosporiose, os cafeeiros a pleno sol obtiveram maiores valores de incidência da doença, seguidos por cafeeiros x grevílea, e menores taxas da doença foram observadas no consórcio cafeeiros x ingazeiro. A incidência de radiação solar direta pode ter favorecido a maior incidência de cercosporiose nos cafeeiros a pleno sol.


The present work aimed to evaluate the incidence of rust and coffee plant cercosporiose in different systems of agroforest cultivation and in the full sunshine through the progress curve of those diseases. The completely randomized design with three treatments and seven replicates was utilized. The treatments were made up of coffee plants mixed with ingazeiro, coffee plants mixed with grevílea and coffee plants cultivated conventionally in the full sunshine. The evaluations were performed monthly during the period of April 2001 to March 2003. The calculation of the area bellow the disease progress curve (ABDPC), which was submitted to the variance analysis. For the incidence of the coffee plant rust, the coffee plant x ingazeiro mixing presented the highest indices of the disease, the treatments coffee plant x grevílea mixing and coffee plant in the full sunshine did no differ from each other and presented the smallest indices of the disease. Decrease in the direct solar light and higher humidity may have supported rust in the coffee plant x ingazeiro system. For the incidence of cercosporiose, the coffee plants in the full sunshine obtained higher values of incidence of the disease followed by coffee plants x grevílea and lowest rates of the disease were found in the coffee plant x ingazeiro mixings. The incidence of direct solar radiation may have supported the highest incidence of cercosporiose on the coffee plants in the full sunshine.

15.
Ciênc. agrotec., (Impr.) ; 31(3): 748-757, maio-jun. 2007. tab, graf
Artículo en Portugués | LILACS | ID: lil-456904

RESUMEN

O sucesso de sistemas de produção sustentáveis tem como aspecto fundamental a escolha das espécies. O conhecimento da tolerância da Brachiaria brizantha (Hochst. ex A. Rich.) Stapf ao sombreamento e seu desempenho em consórcio com eucalipto implica na recomendação desta forrageira para implantação de sistemas agrossilvipastoris. O objetivo deste trabalho foi avaliar quantitativa e qualitativamente a produtividade de Brachiaria brizantha (Hochst. ex A. Rich.) Stapf cv. Marandu sob diferentes arranjos estruturais de sistema agrossilvipastoril com eucalipto. Realizou-se o plantio de mudas clonais de um híbrido natural de Eucalyptus camaldulensis Dehnh com Eucalyptus urophylla S.T. Blake, em dezembro de 1999, em área de cerrado, no noroeste de Minas Gerais (Paracatu MG, Brasil). Fez-se o plantio em consórcio com arroz no primeiro ano, soja no segundo e em seguida braquiária, semeada em dezembro de 2001. O experimento foi implantado no delineamento blocos casualizados, em esquema de parcelas subdivididas, com quatro repetições. Nas parcelas foram alocados os arranjos do eucalipto, em linhas duplas: (3 x 3)+10m, (3 x 4)+7 m, (3 x 4)+10 m, (3 x 4)+7+10 m, (3 x 3)+15 m; e linhas simples: 10x3m, e 10x4m. As subparcelas corresponderam às avaliações na linha e na entrelinha de plantio. Foram avaliados o rendimento e aspectos de qualidade da forragem, bem como a densidade de fluxo de fótons fotossinteticamente ativos no sub-bosque, em cada arranjo. Verificou-se que a forragem disponível (matéria natural e matéria seca) foi sempre maior na entrelinha do que na linha de plantio, independente do arranjo. Os variados arranjos do sistema agrossilvipastoril praticamente não provocaram variação no teor de fibras, N e P na forragem. As concentrações de Ca, K e Mn foram maiores na braquiária sob as linhas de plantio do eucalipto e as concentrações de Mg e Zn maiores na entrelinha de plantio.


The choice of species is the main factor on the establishment of the sustainable system production. The tolerance of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf for shade let this species to be recommended to implement the sylvopastoral and agrosylvopastoral systems. The objective of this work was to evaluate the productive performance of Brachiaria brizantha (Hochst. ex A. Rich.) Stapf cv. Marandu under different spacings on agrosylvopastoral systems with eucalypt. In December 1999 was planted (in Paracatu MG, Brasil) seedling seed orchard of natural hybrid of Eucalyptus camaldulensis Dehnh x Eucalyptus urophylla S.T. Blake, intercropped with rice in the first year and soybean in the second one. After annual cropping cultivation, was planted the forage, in December 2001. The experimental design used was the randomized blocks, with four repetitions, in split plot, and seven spacings of eucalypt stand [(3x3)+10m, (3x4)+7m, (3x4)+10m, (3x4)+7+10m, (3x3)+15m, 10x3m and 10x4m]. Each split plots, the forage was planted in row and between rows of eucalypt. The photosynthetic photon flux density understory of the stand, the natural and dry matter production and forage quality of Brachiaria brizanhta pasture was evaluated. The results showed that the Brachiaria brizantha forage was higher between rows (shaded) than in rows, independent of the spacing, which not promoted changes in the grass content fiber. There were not significant different among spacings or rows and between rows to N and P nutrients content in forage, but the Ca, K and Mn content were highest under rows.

16.
Sci. agric ; 62(5)2005.
Artículo en Inglés | LILACS-Express | VETINDEX | ID: biblio-1496582

RESUMEN

Hanging beef carcasses in different configurations in the cooler affect some carcass muscle tenderness. Forty Nellore steer carcasses (ten per day) were chosen at random in a federally inspected slaughter plant and hanged alternate left and right sides either in the traditional way by the hindquarter (HQ) or by the forequarter (FQ) also called "tenderbife". Carcasses were selected from steers up to 30 months old and had an average hot carcass weight of 244.1 kg. These carcasses were chilled for 48 hours, when samples from the Longissimus dorsi (LD) at the 12th rib and the Biceps femoris (BF) at the P8 site were removed, kept under refrigeration (0-2ºC) for five days and frozen for future analysis. The temperature of the LD after 24 hours taken at the 12th rib was not different for HQ (1.0ºC) and FQ (0.9ºC). Fat thickness measured at the 12th rib was lower (P 0.05) for HQ (3.8 mm) than FQ (4.3 mm). All samples were thawed during 48 hours under refrigeration for tenderness evaluation. Warner Bratzler Shear force from the LD was lower (P 0.001) for FQ (3.53 kg) than HQ (4.78 kg) and was not different for BF. Total cooking losses were not different between HQ (19.7%) and FQ (18.9%). Hanging beef carcass by the forequarter caused an improvement in tenderness of the LD without any detrimental effect on the BF (cap of rump).


A suspensão da carcaça em diferentes formas na câmara fria influencia a maciez de alguns músculos da carcaça. As carcaças de 40 novilhos Nelore (dez por dia) com no máximo 30 meses de idade foram selecionadas ao acaso em frigorífico (SIF 2543) e lados alternados de suas carcaças foram resfriados e pendurados pelo Tendão de Aquiles do traseiro especial (TA) ou pelo músculo carpo radial dianteiro (DA), também chamado "tenderbife". Todas as carcaças eram de classificação B no Sistema Brasileiro de Tipificação de Carcaças, com média de peso de carcaça quente de 244,1 kg. O pH 24 horas não diferiu para os tratamentos, (TA = 5,69 e DA = 5,70). As carcaças foram resfriadas por 48 horas e a seguir, amostras do Longissimus dorsi (LD) na altura da 12ª costela e Biceps femoris (BF) na altura do sítio P8 foram removidas, mantidas sob refrigeração (0-2ºC) por mais 5 dias e a seguir congeladas para posterior análises. A espessura de gordura medida na altura da 12ª costela foi menor (P 0,05) para TA (3,8 mm) do que DA (4,3 mm). A força de cisalhamento do músculo LD foi menor (P 0,01) para o DA (3,53 kg) do que para o TA (4,78 kg) e não foi estatisticamente diferente para o músculo BF. As perdas totais ao cozimento também não foram estatisticamente diferentes (TA = 19,7% e DA = 18,9%). O resfriamento da carcaça pendurada pelo dianteiro ocasionou uma melhoria significativa na maciez do músculo LD (contra-filé) sem causar um efeito indesejável no músculo BF (picanha).

17.
Sci. agric. ; 62(5)2005.
Artículo en Inglés | VETINDEX | ID: vti-440013

RESUMEN

Hanging beef carcasses in different configurations in the cooler affect some carcass muscle tenderness. Forty Nellore steer carcasses (ten per day) were chosen at random in a federally inspected slaughter plant and hanged alternate left and right sides either in the traditional way by the hindquarter (HQ) or by the forequarter (FQ) also called "tenderbife". Carcasses were selected from steers up to 30 months old and had an average hot carcass weight of 244.1 kg. These carcasses were chilled for 48 hours, when samples from the Longissimus dorsi (LD) at the 12th rib and the Biceps femoris (BF) at the P8 site were removed, kept under refrigeration (0-2ºC) for five days and frozen for future analysis. The temperature of the LD after 24 hours taken at the 12th rib was not different for HQ (1.0ºC) and FQ (0.9ºC). Fat thickness measured at the 12th rib was lower (P 0.05) for HQ (3.8 mm) than FQ (4.3 mm). All samples were thawed during 48 hours under refrigeration for tenderness evaluation. Warner Bratzler Shear force from the LD was lower (P 0.001) for FQ (3.53 kg) than HQ (4.78 kg) and was not different for BF. Total cooking losses were not different between HQ (19.7%) and FQ (18.9%). Hanging beef carcass by the forequarter caused an improvement in tenderness of the LD without any detrimental effect on the BF (cap of rump).


A suspensão da carcaça em diferentes formas na câmara fria influencia a maciez de alguns músculos da carcaça. As carcaças de 40 novilhos Nelore (dez por dia) com no máximo 30 meses de idade foram selecionadas ao acaso em frigorífico (SIF 2543) e lados alternados de suas carcaças foram resfriados e pendurados pelo Tendão de Aquiles do traseiro especial (TA) ou pelo músculo carpo radial dianteiro (DA), também chamado "tenderbife". Todas as carcaças eram de classificação B no Sistema Brasileiro de Tipificação de Carcaças, com média de peso de carcaça quente de 244,1 kg. O pH 24 horas não diferiu para os tratamentos, (TA = 5,69 e DA = 5,70). As carcaças foram resfriadas por 48 horas e a seguir, amostras do Longissimus dorsi (LD) na altura da 12ª costela e Biceps femoris (BF) na altura do sítio P8 foram removidas, mantidas sob refrigeração (0-2ºC) por mais 5 dias e a seguir congeladas para posterior análises. A espessura de gordura medida na altura da 12ª costela foi menor (P 0,05) para TA (3,8 mm) do que DA (4,3 mm). A força de cisalhamento do músculo LD foi menor (P 0,01) para o DA (3,53 kg) do que para o TA (4,78 kg) e não foi estatisticamente diferente para o músculo BF. As perdas totais ao cozimento também não foram estatisticamente diferentes (TA = 19,7% e DA = 18,9%). O resfriamento da carcaça pendurada pelo dianteiro ocasionou uma melhoria significativa na maciez do músculo LD (contra-filé) sem causar um efeito indesejável no músculo BF (picanha).

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