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Caracterização morfológica do fruto, semente e morfofunção de plântulas de sapoteira-preta (Diospyros ebenaster Retz.)
Get PDFDiospyros ebenaster, native to México and Central America, Ebenaceae family, is populary known as black-sapote. The fruits can be consumed freshly or as juice, as source of vitamin C. The objective of this work was to characterize the morphology of fruit, of seed and germinative process of this species. Fruits were characterized for color, texture, consistency and water content in the pericarp, dehiscence, weight, dimensions and constituent parts. For seeds it was considered: weight, color, texture and consistency of the coat, shape, presence and type of tissue and type of booking, color, shape and position of the embryo. The description of the seedlings was carried out from the primary root emission to the expansion of the first leaf and early demise of the cotyledons. The fruit is pulpous, undeiscent, bacoid type, polyspermic, round and flattened in the poles. The epicarp is plain, fine and greenish. The mean length of the fruits is 8.8 cm, the mean diameter 8.6 cm and the mass of 263 g. The seeds presents flat tegument and medium-brown color. The mass of 100 seeds is 100.6 g. The mean length of the seeds is 2.2 cm, with 1.3 cm of width. They have a white-transparent and oleaginous endosperm. The embryo is whitish and the germination is epigeal.Diospyros ebenaster, originária do México e América Central, família Ebenaceae, é conhecida como sapota-preta. Os frutos podem ser consumidos in natura ou em sucos, como fonte de vitamina C. O objetivo deste trabalho foi caracterizar a morfologia do fruto, da semente e do processo germinativo da espécie. Os frutos foram caracterizados quanto à coloração, textura, consistência e teor de água no pericarpo, deiscência, massa, partes constituintes e dimensões. Para as sementes considerou-se: massa, coloração, textura e consistência do tegumento, forma, presença e tipo de tecido de reserva e tipo, coloração, forma e posição do embrião. A descrição das plântulas foi realizada a partir da emissão da raiz primária até a expansão dos primeiros eófilos e início de fenecimento dos cotilédones. O fruto é carnoso, indeiscente, do tipo baga, polispérmico, globoso e achatado nos pólos. O epicarpo é liso, delgado e esverdeado. O comprimento médio dos frutos é 8,8 cm, o diâmetro médio 8,6 cm e a massa de 263 g. As sementes apresentam tegumento liso e cor castanho-médio. A massa de 100 sementes é 100,6 g. O comprimento médio das sementes é 2,2 cm, com 1,3 cm de largura. Possuem endosperma branco-transparente e oleaginoso. O embrião é esbranquiçado e a germinação é epígea
Bactérias diazotróficas associativas: diversidade, ecologia e potencial de aplicações
Get PDFAbstractBiological nitrogen fixation (BNF) is carried out by representatives of various bacterial phylogeneticgroups named diazotrophs. These bacteria can live free in many ecosystems and/or establishingsymbiosis or associations with diverse plant species. These last ones are called associative diazotrophs.Associative diazotrophic bacteria can contribute to plant growth by improving N-nutrition as wellas by other processes like hormone production, phosphate solubilization, biological control, amongothers. This review presents different genera of associative diazothophs regarding their taxonomicposition, ecological features and process they mediated related to plant growth promotion. It alsoshows how modifications in ecosystems influence density and diversity of these bacteria.A fixação biológica de nitrogênio (FBN) é realizada por representantes de diversos gruposfilogenéticos bacterianos, que são denominados diazotróficos. Estas bactérias podem viver livresem diversos ecossistemas, estabelecer simbioses ou estar associados às plantas, sendo neste últimocaso denominados de diazotróficas associativas. As bactérias diazotróficas associativas podemcontribuir para o crescimento vegetal não só pelo fornecimento de nitrogênio, mas também poroutros mecanismos como produção de fitormônios, solubilização de fosfatos, antagonismo afitopatógeno, entre outros. Esta revisão aborda os diferentes gêneros de diazotróficos associativose discute aspectos relacionados à taxonomia, ecologia e processos de promoção do crescimentovegetal e ainda como as alterações dos ecossistemas atuam na diversidade e densidade destasbactérias. Diazotrophic associative bacteria: diversity, ecology and potential applicationsAbstractBiological nitrogen fixation (BNF) is carried out by representatives of various bacterial phylogeneticgroups named diazotrophs. These bacteria can live free in many ecosystems and/or establishingsymbiosis or associations with diverse plant species. These last ones are called associative diazotrophs.Associative diazotrophic bacteria can contribute to plant growth by improving N-nutrition as wellas by other processes like hormone production, phosphate solubilization, biological control, amongothers. This review presents different genera of associative diazothophs regarding their taxonomicposition, ecological features and process they mediated related to plant growth promotion. It alsoshows how modifications in ecosystems influence density and diversity of these bacteria
Estabilidade de agregados e distribuição do carbono em Latossolo sob sistema plantio direto em Uberaba, Minas Gerais
Get PDFThe use of no-tillage system (SNT) with cover plants improves soil aggregation. The aim of this study was to evaluate the stability of aggregates in water and carbon distribution in different aggregates class in Oxisol in no-tillage system, Uberaba, MG, Brazil. It was evaluated two areas in SNT: crop of corn + brachiaria and corn + crotalaria. An area adjacent to the savanna was taken as a condition of the original soil. It was collected samples of soil deformability 0-5 and 5-10 cm, soil depths which was evaluated the stability of aggregates stable in water, by means of indices of aggregation: mean weight diameter (MWD) and geometric mean diameter (GMD). It was also evaluated the distribution of the mass of aggregates and carbon per sieve class. It was found that, regardless of depth, the area of savanna showed higher values for DMP, DMG and carbon. Among the cultivated areas, the system of crop corn + brachiaria showed higher values of DMP and carbon of aggregates in detriment of the area corn + crotalaria. These results indicate that the crop in SNT of corn + brachiaria increases soil aggregation and carbon aggregates when compared to the system of corn + crotalaria.O uso do sistema plantio direto (SPD) com plantas de cobertura melhora a agregação do solo. O objetivo desse trabalho foi avaliar a estabilidade dos agregados em água e a distribuição do carbono nas diferentes classes de agregados de Latossolo Vermelho em sistema plantio direto, em Uberaba, MG. Foram avaliadas duas áreas em SPD: cultivo de milho + braquiária e milho + crotalária. Uma área de cerrado natural adjacente às áreas foi tomada como condição original do solo. Foram coletadas amostras de solo indeformadas nas profundidades de 0-5 e 5-10 cm, sendo avaliada a estabilidade dos agregados estáveis em água, por meio dos índices de agregação: diâmetro médio ponderado (DMP) e diâmetro médio geométrico (DMG). Também foi avaliada a distribuição da massa dos agregados e carbono por classe de peneira. Verificou-se que, independente da profundidade, a área de cerrado apresentou os maiores valores de DMP, DMG e carbono. Entre as áreas cultivadas, o sistema de cultivo de milho + braquiária apresentou maiores valores de DMP e carbono dos agregados em detrimento a área de milho + crotalária. Estes resultados indicam que o cultivo em SPD do milho + braquiária aumenta a agregação do solo e o carbono dos agregados quando comparado ao sistema de milho + crotalária. Aggregate stability and carbon distribution in Oxisol under no-tillage system inUberaba, Minas Gerais State, BrazilAbstractThe use of no-tillage system (SNT) with cover plants improves soil aggregation. The aim of this studywas to evaluate the stability of aggregates in water and carbon distribution in different aggregatesclass in Oxisol in no-tillage system, Uberaba, MG, Brazil. It was evaluated two areas in SNT: crop ofcorn + brachiaria and corn + crotalaria. An area adjacent to the savanna was taken as a conditionof the original soil. It was collected samples of soil deformability 0-5 and 5-10 cm, soil depths whichwas evaluated the stability of aggregates stable in water, by means of indices of aggregation:mean weight diameter (MWD) and geometric mean diameter (GMD). It was also evaluated thedistribution of the mass of aggregates and carbon per sieve class. It was found that, regardless ofdepth, the area of savanna showed higher values for DMP, DMG and carbon. Among the cultivatedareas, the system of crop corn + brachiaria showed higher values of DMP and carbon of aggregatesin detriment of the area corn + crotalaria. These results indicate that the crop in SNT of corn +brachiaria increases soil aggregation and carbon aggregates when compared to the system ofcorn + crotalaria.
Genotoxicity of Chlorpyrifos and the Antimutagenic Role of Lettuce Leaves in Male Mice
Get PDFChlorpyrifos [O O-diethyl-O-(3 5 6-trichloro-2-pyridyl)-phosphorothioate] is one of the most widely used organophosphate insecticides. Previous studies proved that chlorpyrifos, at different doses, induced genotoxicity. In Egyptian foods, the residual levels of pesticides are often higher than those found in developed country ones. So the aim of this research was to evaluate the genotoxicity of the insecticide chlorpyrifos at doses equal to its maximum residue limit (MRL) in the leafy vegetables, its double and quadruple (0.5, 1 and 2 mg/kg body weight) in somatic and germ cells of male mice. In addition to that, evaluating the role of lettuce leaves as antigenotoxic in reducing the genotoxic effects of chlorpyrifos tested doses when concurrently administrated to these animals. The study was conducted on adult male laboratory mice at three levels: bone marrow cells as a model for mitotic chromosome aberrations, spermatocytes as a model for meiotic chromosomes and sperm count and morphology. The results of the present study indicate that the treatment of male mice with chlorpyrifos by oral gavages for three months induced significant increase in the frequencies of total chromosomal aberrations in both somatic and germ cells in relation to control groups. Results of the sperm analysis showed that chlorpyrifos induced significant decrease in the sperm count when compared to negative control. Furthermore, it induced significant increase in head and tail sperm abnormalities, among which coiled tail was considered the most obvious sperm abnormality induced by chlorpyrifos. At the same time, the present study indicated that lettuce leaves feed concurrently with three doses of chlorpyrifos could not protect cells from damage.Chlorpyrifos [O O-diethyl-O-(3 5 6-trichloro-2-pyridyl)-phosphorothioate] is one of the most widely used organophosphate insecticides. Previous studies proved that chlorpyrifos, at different doses, induced genotoxicity. In Egyptian foods, the residual levels of pesticides are often higher than those found in developed country ones. So the aim of this research was to evaluate the genotoxicity of the insecticide chlorpyrifos at doses equal to its maximum residue limit (MRL) in the leafy vegetables, its double and quadruple (0.5, 1 and 2 mg/kg body weight) in somatic and germ cells of male mice. In addition to that, evaluating the role of lettuce leaves as antigenotoxic in reducing the genotoxic effects of chlorpyrifos tested doses when concurrently administrated to these animals. The study was conducted on adult male laboratory mice at three levels: bone marrow cells as a model for mitotic chromosome aberrations, spermatocytes as a model for meiotic chromosomes and sperm count and morphology. The results of the present study indicate that the treatment of male mice with chlorpyrifos by oral gavages for three months induced significant increase in the frequencies of total chromosomal aberrations in both somatic and germ cells in relation to control groups. Results of the sperm analysis showed that chlorpyrifos induced significant decrease in the sperm count when compared to negative control. Furthermore, it induced significant increase in head and tail sperm abnormalities, among which coiled tail was considered the most obvious sperm abnormality induced by chlorpyrifos. At the same time, the present study indicated that lettuce leaves feed concurrently with three doses of chlorpyrifos could not protect cells from damage.Genotoxidade de Chlorpyrifos e papel antimutagênico das folhas de alfaces em ratosResumoChlorpyrifos [O O-diethyl-O-(3 5 6-trichloro-2-pyridyl)-phosphorothioate] é um dos inseticidades a basede organofosfato mais utilizados. Estudos anteriores provaram que chlorpyrifos, em doses diferentes,induziu a genotoxidade. Em alimentos egípcios, os níveis residuais de pesticidas são normalmentemais elevados que aqueles encontrados em países desenvolvidos. Então, o objetivo dessa pesquisafoi o de avaliar a genotoxidade do inseticida chlorpyrifos em doses iguais ao limite residual máximo(MRL) em vegetais com folhas, seu dobro e quádruplo (0.5, 1 and 2 mg/kg peso corpóreo) emcélulas somáticas e germinativas de ratos. Além disso, avaliando o papel das folhas de alfacecomo antígenos tóxicos na redução dos efeitos de genotoxidade em doses de chlorpyrifos testadasquando administradas a esses animais. O estudo foi conduzido em ratos adultos de laboratório, emtrês níveis: células ósseas como modelo para aberrações miótico-cromossômicas; espermatócitoscomo modelo meiótico-cromossômico, contagem e morfologia de espermatozóides. Os resultadosdo presente estudo indicaram que o tratamento de ratos com chlorpyrifos, administrado emdoses orais por três meses induziram um significativo aumento da freqüência de aberraçõescromossômicas totais tanto em células somáticas quanto em células germinativas se relacionadosaos grupos de controle. Os resultados da análise de espermatozóide demonstraram que chlorpyrifosinduziu uma diminuição significativa na contagem de espermatozóides quando comparado aogrupo de controle negativo. Além disso, também houve a indução de um aumento significativoem anomalias na cabeça e na cauda dos espermatozóides, dentre as quais a cauda enroladafoi considerada a anomalia mais óbvia entre os espermatozóides induzidos por chlorpyrifos. Aomesmo tempo, o presente estudo indicou que as folhas de alface alimentadas regularmente comtrês doses de chlorpyrifos não conseguiram proteger suas células de danos.
Yield and agronomic caracteristics of soybean breeding lines in Minas Gerais State, Brazil
Get PDFThis study evaluated yield performance of lines in the trial network of the Soybean Breeding Program of Universidade Federal de Uberlândia, in Uberaba-MG. The experiment was done at the Experimental Farm of Faculdades Associadas de Uberaba - FAZU, in the season 2007/2008, with plots consisting of four 5.0-m long rows spaced by 0.50 m. The agricultural characteristics evaluated were: plant height at flowering, plant height at maturation, insertion height of the first pod, number of days for flowering, number of days to maturity, yield and lodging, in late cycle soybean. The lines UFU-518 with 4300.3 kg ha-1 and UFU-513 with 3810.2 kg ha-1 were the most productive, with performance above the commercial controls.This study evaluated yield performance of lines in the trial network of the Soybean Breeding Program of Universidade Federal de Uberlândia, in Uberaba-MG. The experiment was done at the Experimental Farm of Faculdades Associadas de Uberaba - FAZU, in the season 2007/2008, with plots consisting of four 5.0-m long rows spaced by 0.50 m. The agricultural characteristics evaluated were: plant height at flowering, plant height at maturation, insertion height of the first pod, number of days for flowering, number of days to maturity, yield and lodging, in late cycle soybean. The lines UFU-518 with 4300.3 kg ha-1 and UFU-513 with 3810.2 kg ha-1 were the most productive, with performance above the commercial controls.Características agronômicas e produtividade de linhagens de soja em Minas GeraisResumoO objetivo deste trabalho foi avaliar o desempenho produtivo de linhagens da rede de ensaios do programa de melhoramento de soja da Universidade Federal de Uberlândia em Uberaba-MG. O experimento foi realizado na Fazenda experimental da Faculdades Associadas de Uberaba - FAZU, na safra 2007/2008, as parcelas foram constituídas por 4 linhas espaçadas entre si de 0,50 m com 5,0 m de comprimento. As avaliações agronômicas foram: altura da planta na floração, altura da planta na maturação, altura de inserção da primeira vagem, dias para a floração, dias para a maturidade, produtividade e acamamento, em soja do ciclo tardio. As linhagens UFU-518 com 4300,3 Kg ha-1 e a UFU-513 com 3810,2 Kg ha-1 foram as mais produtivas, com desempenho superior às testemunhas
Growth and productivity of okra intercropped with kale in direct planting under organic management
Get PDFThe cultivation of vegetables in intercropping and direct planting are alternatives with greater economic, social and environmental efficiency. In this sense, the objective of this study was to evaluate the effect of different plant arrangement systems on the intercropping of okra and kale, as well as on the efficiency of use of the area. The experiment was conducted at the experimental station belonging to Unioeste, from May 2017 to March 2018 in direct planting, under organic management, using a randomized block design, containing seven treatments and four replications. The treatments consisted of the following arrangements of okra and kale plants in a consortium, T1 = three rows of kale with okra between the lines; T2 = three rows of kale with okra between the lines; T3 = three rows of kale with okra dense between the lines; T4 = three rows of kale with okra dense spaced between alternating lines; and monoculture T5 = three rows of kale; T6 = three rows of okra; T7 = three rows of dense okra. Assessments began 50 and 73 days after transplanting for kale and okra, respectively. Biometric and productivity variables were evaluated. The data were subjected to variance analysis and, when significant, regression analysis depending on the evaluation periods or compared using the Tukey test at 5% probability. It is concluded, that the okra crop showed greater productivity when grown in dense monoculture, and all intercropping systems promoted greater efficiency in land use.The cultivation of vegetables in intercropping and direct planting are alternatives with greater economic, social and environmental efficiency. In this sense, the objective of this study was to evaluate the effect of different plant arrangement systems on the intercropping of okra and kale, as well as on the efficiency of use of the area. The experiment was conducted at the experimental station belonging to Unioeste, from May 2017 to March 2018 in direct planting, under organic management, using a randomized block design, containing seven treatments and four replications. The treatments consisted of the following arrangements of okra and kale plants in a consortium, T1 = three rows of kale with okra between the lines; T2 = three rows of kale with okra between the lines; T3 = three rows of kale with okra dense between the lines; T4 = three rows of kale with okra dense spaced between alternating lines; and monoculture T5 = three rows of kale; T6 = three rows of okra; T7 = three rows of dense okra. Assessments began 50 and 73 days after transplanting for kale and okra, respectively. Biometric and productivity variables were evaluated. The data were subjected to variance analysis and, when significant, regression analysis depending on the evaluation periods or compared using the Tukey test at 5% probability. It is concluded, that the okra crop showed greater productivity when grown in dense monoculture, and all intercropping systems promoted greater efficiency in land use