RESUMO A caracterização da diversidade genética, com base na avaliação da germinação e do vigor de sementes, é uma etapa fundamental para dar inicio ao desenvolvimento do sistema de cultivo de C. procera. Dessa maneira, objetivou-se estimar a divergência genética em genótipos de C. procera baseada na germinação e no vigor de sementes armazenadas por doze meses. Foram utilizados 35 genótipos, oriundos de áreas de ocorrência natural na Paraíba, coletados e armazenados em março de 2014. Para a avaliação do potencial fisiológico das sementes, foram realizados dois experimentos entre março e abril de 2015. O primeiro constou de um ensaio de germinação conduzido em câmara de germinação, enquanto o segundo, de um ensaio de emergência em areia lavada, realizado em bandejas de polietileno no interior de ambiente de telado em condições não controladas. Em ambos os experimentos foi utilizado o delineamento inteiramente casualizado com quatro repetições de 25 sementes por genótipo. As características avaliadas foram germinação, a germinação média diária, a velocidade diária de germinação, o índice de velocidade de germinação, o tempo médio de germinação, o índice de vigor de plântulas, a emergência, o índice de velocidade de emergência, o comprimento total e a fitomassa seca total. Entre os genótipos de C. procera existe variabilidade genética para variáveis de germinação e vigor de sementes armazenadas por um ano. As características de emergência, fitomassa seca total de plântula e germinação são as que mais contribuem para a divergência genética em genótipos de C. procera. | ABSTRACT Characterizing genetic diversity based on evaluations involving germination and seed vigor, is a fundamental stage in starting the development of a cultivation system for Calotropis procera. Thus, this study aimed to estimate genetic diversity among 35 C. procera genotypes based on germination and vigor of seeds stored for 1 year. The genotypes, which originated from areas in Paraíba (Brazil), where they occur naturally, were collected and stored in March 2014. In order to evaluate the physiological potential of the seeds, two experiments were conducted between March and April 2015. The first involved a propagation test conducted in a germination chamber, while the second involved an emergence test in washed sand, performed in polyethylene trays in a screened environment under uncontrolled conditions. In both experiments, an entirely randomized design was used, with four repetitions of 25 seeds per genotype. The characteristics evaluated were germination, average daily germination, daily germination speed, the speed of germination index, the plantlet vigor index, emergence, the speed of emergence index, total length, and total dry mass. The results showed that genetic variability exists among the C. procera genotypes for variables involving germination and vigor of seeds stored for 1 year. Also, emergence, total dry plantlet mass, and germination characteristics contribute most to the genetic divergence among C. procera genotypes.

ABSTRACT The cowpea [Vigna unguiculata (L.) Walp.], also known as cowpea, is of fundamental socioeconomic importance to the northeast of Brazil, and has become one of the main sources of protein in the diet of the rural population. However, in this region, it has become necessary to identify genotypes that are better adapted to drought. In addition, research is needed regarding the action of substances that promote tolerance to stress factors. The aim of this study was to evaluate the antioxidative response of cowpea cultivars under osmotic stress conditions using potassium nitrate as an attenuator. Five osmotic potentials were tested in the substrate (0.0, −0.2, −0.4, −0.6, and −0.8 MPa), and three seed treatments (pre-soaking in distilled water, pre-soaking in potassium nitrate, and without pre-soaking) were tested in three cowpea cultivars (BRS Itaim, BRS Aracê, and BRS Potengi). The design was randomized with 45 treatments and four replications. The data were submitted to analysis of variance (P < 0.05), and in cases of significance, regression analysis was conducted to quantitate the factors. Our results indicate that an increase in proline content in cowpea plants may be seen as indicative of the intensity of water stress on germination and the initial stages of growth of the plant. The BRS Itaim cultivar best tolerates drought conditions with the application of potassium nitrate, given the increased activity of antioxidant enzymes such as superoxide dismutase, catalase, and ascorbate peroxidase. | RESUMO O feijão-caupi [Vigna unguiculata (L.) Walp.], também conhecido como feijão macassar, representa fundamental importância socioeconômica para o Nordeste do Brasil, constituindo-se como uma das principais fontes proteicas na alimentação da população rural. Todavia, nessa região é necessário identificar genótipos mais adaptados ao déficit hídrico, bem como conhecer a ação de substâncias promotoras de tolerância a fatores de estresse. O objetivo desse trabalho foi avaliar a resposta antioxidativa de cultivares feijão-caupi sob condições de estresse osmótico, utilizando como atenuador o nitrato de potássio. Foram testados cinco potenciais osmóticos no substrato (0,0; -0,2; -0,4; -0,6 e -0,8 MPa) e três tratamentos de sementes (pré-embebição em água destilada; pré-embebição em nitrato de potássio e sem pré-embebição) em três cultivares (BRS Itaim, BRS Aracê e BRS Potengi). Foi adotado o delineamento inteiramente casualizado, com quatro repetições e sementes por repetição. Os dados obtidos foram submetidos à análise de variância (P<0,05) e nos casos de significância foi realizada a análise de regressão para fator de natureza quantitativa. Os resultados indicam que um aumento no teor de prolina em feijão-caupi pode ser visto como indicativo da intensidade do estresse hídrico na germinação e nos estágios iniciais de crescimento da planta. A cultivar BRS Itaim tolera melhor as condições de seca com a aplicação de nitrato de potássio,dado o aumento da atividade de enzimas antioxidantes como superóxido dismutase, catalase e ascorbato peroxidase.

RESUMO A fração pirolenhosa obtida com a carbonização da madeira pode ser utilizada para diversos fins. Sendo assim, este trabalho teve por objetivo testar o licor pirolenhoso extraído durante o processo de carbonização de resíduos florestais no desenvolvimento vegetativo da orquídea Oeceoclades maculata. As concentrações do licor pirolenhoso utilizadas nos tratamentos foram: T1 = 0 ml.L-1, T2 = 1 ml.L-1, T3 = 2 ml.L-1, T4 = 3 ml.L-1, T5 = 4 ml.L-1 e T6 = 5 ml.L-1, esses tratamentos foram testas com e sem carvão ativado no desenvolvimento in vitro e ex vitro da orquídea. As seguintes características dos protocórmos desenvolvidos in vitro foram avaliadas: com fungo, sem desenvolvimento, em desenvolvimento, presença de folhas e raízes. Para o desenvolvimento ex vitro foram avaliados: Tamanho das folhas, tamanho e número de raízes, altura total da planta, quantidade de gemas. Possíveis diferenças entre os tratamentos foram testada por meio de Análise de variância (ANOVA) e teste de Tukey a 5% de significância. O uso do licor pirolenhoso em dosagem pequenas mostrou-se significativo no desenvolvimento dos tecidos vegetativos e na formação radicular e foliar de Oeceoclades maculata, uma vez que apresenta todos os elementos minerais essenciais ao desenvolvimento estrutural da planta. | ABSTRACT Pyroligneous fraction from wood carbonization can be used for several purposes. In this sense, this study aimed to test a pyroligneous liquor extracted during carbonization of forest residues for the vegetative development of the orchid Oeceoclades maculata. The concentrations of pyroligneous liquor used in the treatments were T1 = 0 mL L−1, T2 = 1 mL L−1, T3 = 2 mL L−1, T4 = 3 mL L−1, T5 = 4 mL L−1, and T6 = 5 mL L−1. These treatments were tested together with and without activated charcoal for in vitro and ex vitro propagation. In vitro developed protocorms were assessed according to development or not, the presence of fungus, leaves, and roots. For ex vitro evaluations, leaf size, size, the number of roots, total plant height, and the number of buds were assessed. Possible differences between treatments were tested by means of analysis of variance (ANOVA) and Tukey’s test at 5% significance. The use of pyroligneous liquor at low doses was significant in vegetative tissue development as well as for root and leaf formations in O. maculata seedlings since it presents all the essential mineral elements to the structural development of these plants.

ABSTRACT The objective of this work was to evaluate seeds of cowpea, cultivar BRS Tumucumaque, subjected to different water stresses induced by polyethylene glycol (PEG-6000) and mannitol and different salt stresses induced by NaCl and CaCl2 solutions. The water and salt stresses was evaluated in laboratory using completely randomized experimental designs in 2x6 factorial arrangements, with six osmotic potentials (0.0, -0.2, -0.4, -0.6, -0.8 and -1.0 MPa) and two stress inducers for each experiment, with four replications of 50 seeds. The percentage of germination, germination speed index, root and shoot lengths and seedling fresh weight were evaluated at the tenth day (end of the evaluation period). The simulated water stress showed effects on the cowpea seed germination and seedling initial growth by decreasing the rates of the variables evaluated, which had greater effect in treatments with PEG-6000. The salt stress induced by NaCl showed greater effect on the variables evaluated than that induced by CaCl2, due to the sodium toxicity in the salt chemical composition. | RESUMO O objetivo deste trabalho foi avaliar o comportamento de sementes das sementes da cultivar de feijão-caupi BRS Tumucumaque sob efeito de potenciais hídricos provocados por polietileno glicol (PEG 6000) e manitol e de potenciais salinos induzidos por soluções de NaCl e CaCl2. Para verificação dos estresses hídrico e salino, avaliou-se em laboratório, a combinação de seis potenciais osmóticos (0,0; -0,2; -0,4; -0,6; -0,8 e -1,0 MPa) com os dois agentes de estresses para cada experimento, em delineamento inteiramente casualizado, configurando esquema fatorial 2x6, com quatro repetições de 50 sementes. Foram avaliadas as variáveis: porcentagem de germinação, índice de velocidade de germinação (IVG), comprimento de raiz e parte aérea e massa fresca de plântulas no décimo dia, ao final do período de avaliação. A simulação de deficiência hídrica, utilizando-se manitol e PEG 6000 permitiu a constatação dos efeitos do estresse na germinação e no crescimento inicial das plântulas da cultivar BRS Tumucumaque, pelo decréscimo das variáveis observadas, sendo que os tratamentos à base de PEG 6000 foram os mais drásticos. A indução do estresse salino pelos sais NaCl e CaCl2 foi verificada nas variáveis avaliadas, onde os efeitos do NaCl foram mais acentuados, devido a toxidade do sódio na composição química do sal.

RESUMO O uso da tecnologia de biofloco (BFT) pode contribuir para a produção de peixes em regiões com reduzida água. Portanto, compreender a dinâmica da qualidade da água é essencial para o sucesso do cultivo de peixes. O objetivo do presente estudo foi avaliar a qualidade da água no cultivo de tilápia do Nilo em sistema sem troca de água, durante a fase de alevinagem, utilizando diferentes fontes de carbono e relações C:N. O delineamento experimental utilizado foi o arranjo fatorial 2x3, contendo duas relações carbono (C) e nitrogênio (N) (10:1 e 20:1) e três fontes de carbono (açúcar, melaço e amido de mandioca). Ambas as relações C:N e fontes de carbono influenciaram as variáveis alcalinidade, sólidos sedimentáveis (SS), turbidez e sólidos suspensos totais (SST) demonstrando valores significativamente mais elevados na relação C:N 20:1 (P < 0,05). As melhores fontes de carbono para a formação de flocos microbianos foram observados na utilização do melaço e açúcar na relação C:N de 10:1 e 20:1. A estabilidade dos parâmetros de qualidade de água monitorados ocorreu entre a 6 e 7 semanas de cultivo. O desempenho de tilapia do Nilo em sistema BFT fertilizado com diferentes fontes de carbono orgânico não foi significativamente diferente (P < 0,05) entre os tratamentos. A escolha de melaço para a fertilização do sistema BFT também pode ajudar a reduzir o custo de produção em regiões onde há disponibilidade deste produto. | ABSTRACT The use of biofloc technology (BFT) can improve fish production in regions with low water availability. Therefore, information on dynamics of water quality is essential for success in fish rearing. Thus, the objective of the present study was to evaluate the water quality for Nile tilapia farming in a system without water exchange, during the fingerling stage, using different sources of carbon and C:N ratios. A completely randomized experimental design was used in a 2x3 factorial arrangement, with two carbon (C) to nitrogen (N) ratios (10:1 and 20:1) and three carbon sources (sugar, molasses and cassava starch). The C:N ratio and carbon source affected the variables alkalinity, settleable solids (SS), turbidity and total suspended solids (TSS), showing significantly higher values at C:N ratio of 20:1 (P < 0.05). The best carbon source for microbial floc formation were the molasses and sugar, under C:N ratios of 10:1 and 20:1. The stability of the monitored water quality parameters occurred from 6 to 7 weeks of rearing. The growth performance of Nile tilapia in BFT system fertilized with different organic carbon sources was not significantly different (P < 0.05) between treatments. The use of molasses to fertilize BFT systems can reduce costs of production in regions where this product is available.

ABSTRACT The control of Spodoptera frugiperda (J. E. SMITH) (Lepidoptera: Noctuidae) has been carried out mainly with pyrethroids and organophosphates insecticides. The continuous and indiscriminate use of synthetic insecticides, for decades, has led to the selection of resistant populations and has caused concerns for human health and the environment. An alternative is the use of botanical insecticides, including through the mixtures with synthetic insecticides. This study aimed to investigate the toxicity of copaiba oil-resin mixtures (COR) with deltamethrin, beta-cyfluthrin, beta-cypermethrin, methomyl, triazophos and chlorpyrifos for S. frugiperda. Bioassays were performed in the laboratory using newly hatched caterpillars on a contaminated surface (filter paper). Initially, concentration-mortality curves were established for each insecticide and COR. Based on the results, experiments were conducted to verify the effect of the COR mixtures with synthetic insecticides in the proportions of 1:1 (LC25 + LC25) on larvae of S. frugiperda. Additionally, COR concentration-response curves were established by adding 1/8 of the recommended rate of each insecticide. Notably, the use of this concentration for all insecticides was previously determined in bioassays, and no significant toxicity was found for S. frugiperda caterpillars. It was found that the toxicity of COR increased substantially by adding synthetic insecticides, especially with lower mixtures with beta-cypermethrin, methomyl and triazophos. | RESUMO O controle de Spodoptera frugiperda (J. E. SMITH) (Lepidoptera: Noctuidae) tem sido realizado principalmente com inseticidas piretróides e organofosforados. O uso contínuo e indiscriminados de inseticidas sintéticos, durante décadas, tem ocasionado a seleção de populações resistentes, bem como preocupações em relação à saúde humana e ao meio ambiente. Uma alternativa é o emprego de inseticidas botânicos, inclusive por meio de misturas com inseticidas sintéticos. Assim, este trabalho teve por objetivo investigar a toxicidade de misturas do óleo-resina de copaíba (ORC) com os inseticidas deltametrina, beta-ciflutrina, beta-cipermetrina, metomil, triazofós e clorpirifós para S. frugiperda. Foram realizados bioensaios em laboratório utilizando-se lagartas recém-eclodidas em superfície contaminada (papel filtro). Inicialmente, foram estabelecidas curvas de concentração-mortalidade para cada inseticida e para o COR. A partir dos resultados obtidos foram realizados bioensaios para verificar o efeito das misturas do ORC com os inseticidas sintéticos nas proporções de 1:1 (CL25 + CL25) sobre lagartas de S. frugiperda. Adicionalmente, foram estabelecidas curvas de concentração-resposta do ORC adicionando-se 1/8 da dose comercial de cada inseticida. Vale destacar que o uso desta fração para todos os inseticidas foi determinada em bioensaios preliminaries, não tendo apresentado toxicidade considerável para as lagartas de S. frugiperda. Constatou-se que a toxicidade do ORC aumentou substancialmente adicionando-se os inseticidas sintéticos, com menor destaque para as misturas com beta-cipermetrina, metomil e triazofós.

The objective of this work was to evaluate the effects of the application of phosphogypsum and vinasse on soil chemical properties and productivity and nutritional characteristics of alfalfa (Medicago sativa). The experiment was conducted in a randomized block design, using a 3×5 factorial arrangement, with three vinasse rates (0, 150 and 300 m3 ha-1) and five phosphogypsum rates (0, 3, 6, 9 and 12 Mg ha-1). The alfalfa chemical composition and shoot dry matter (SDW) and soil chemical properties (in the layers 0.0-0.2 and 0.21-0.4 m) were evaluated. The vinasse rates increased the soil potassium contents, while the phosphogypsum rates promoted linear increases in soil calcium and sulfur contents. The base saturation was increased and the magnesium content showed a quadratic response on the layer 0.21-0.4 m with the increase in phosphogypsum rates. The calcium, magnesium and phosphorus contents in the alfalfa leaves were lower with vinasse application. The phosphogypsum rates promoted linear increases in alfalfa SDW. Vinasse rated 150 m3 ha-1 was been enough to SDW increase. Calcium and magnesium contents in the leaves fitted a quadratic model, with maximum calcium content in the phosphogypsum rate of 9.5 Mg ha-1 and the minimum magnesium content in the phosphogypsum rate of 8.7 Mg ha-1. The leaf sulfur contents in all vinasse rates and leaf potassium contents in the highest vinasse rate showed maximum accumulation at near 9 Mg ha-1 of phosphogypsum.

The objective of this work was to evaluate the response of sugarcane genotypes to Meloidogyne javanica and Pratylenchus zeae . Sugarcane seedlings of the genotypes RB985944, RB987932, RB877935, RB855156, RB935744, RB996961, RB925345, RB935581 and RB966928 obtained from tissue cultures and maintained in pots with sterilized soil in a greenhouse were inoculated with 5,000 eggs + second - stage juveniles of M. javanica or 1,600 of P. zeae per plant, using six replicates per treatment. Tomato (Rutgers) and sorghum (BRS506) plants were used as control and proof of viability of the inoculum for the M. javanica and P. zeae , respectively. The number of root - knot in the plants inoculated with M. javanica , final nematode population and reproduction factor (RF) of both nematodes were evaluated at 120 days after inoculation. The averages of the different variables were compared by the Scott - Knott's clustering test at 5%. The nematodes M. javanica and P. zeae showed RF>1.00 in all sugarcane genotypes assessed, however, different levels of susceptibility were found. The lowest reproduction of the nematodes was found in the genotypes RB008347, RB877935, RB975944 and RB987932 ( M. javanica ) and RB987932 and RB966928 ( P. zeae ).

Forage turnip (Raphanus sativus L. var. oleiferus Metzg.) progeny with seeds of higher physiological quality are of importance for farmers and seed producing companies. The objective of this work was to identify tests to be used in laboratories for the selection of turnip progeny having seeds of higher germination, vigor, seedling emergence in the field, and storage potential. Seeds of 100 turnip progeny of paternal half-sibs were evaluated as to water content, 1,000-seed mass, first count of the standard germination test, accelerated aging, and seedling emergence in the field. The seeds were subjected to storage for 12 months in unifoliate paper bags kept under room conditions and then evaluated by means of the standard germination test, first count of the standard germination test, and water content. The data were examined as to variance and genetic and phenotypic correlations, heritability, coefficients of genetic variation, and selection gain. The standard germination test, first count of germination, and the accelerated aging test can be used to select forage turnip progeny for seed physiological quality and storage potential. None of the tests used were efficient at selecting progeny with high field emergence.

The aim of this study was to evaluate physiological quality in seeds of sweet sorghum grown under semi-arid conditions, and to determine the age of physiological maturity of the seeds as a function of the foliar application of potassium silicate. The experiment was carried out at the Curu Valley Experimental Farm, in Pentecoste in the state of Ceará, during the rainy seasons of 2014 and 2015. The BRS 506 and BRS 511 varieties were used, under foliar fertilisation with potassium silicate at doses of 500, 1000 and 1500 mL.ha -1, in addition to the control lots (with no application); harvesting was at four periods, 30, 37, 44 and 51 days after full bloom (DAB). The percentage and speed of germination were evaluated, together with the accelerated ageing test and seedling growth. The seeds presented greater than 90% germination from 37 DAB, reaching high seedling vigour at 51 DAB. Foliar fertilisation with potassium silicate under the conditions of the experiment resulted in an increase in the physiological quality of the seeds. The BRS 506 and BRS 511 cultivars displayed the highest physiological quality between 49 and 53 DAF.