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Poda de contenção e central em pomar de nogueira-pecã de alta densidade no Sul do Brasil
No full textThis study aimed at evaluating the influence of two pruning methods, as well as absence of pruning, on vegetative and productive development and in the quality of pecan fruits in a high-density orchard. The experiment was conducted with the cultivar Melhorada in a commercial pecan orchard in municipality of Santa Rosa, Rio Grande do Sul (RS), Brazil. The study was carried out between July 2018 and June 2020. In a randomized block design, the following treatments were applied: no pruning, hedge pruning and central pruning. Hedge pruning increased limb growth, while central pruning decreased the number of dry branches. Fruit production oscillated in the cycles. In the first, production was higher when central pruning was conducted. In the second cycle, it was higher in unpruned trees. Even though both pruning methods decreased the number of fruit with closed epicarps, they did not affect most variables of fruit quality. Therefore, results show that pruning methods promote vegetative development of pecan trees, reducing dry branches, but they are inconclusive regarding their production and have no significant effect on the main variables of their fruit quality. The evaluation and continuity of pruning for more cycles is important to obtain the most consistent results for indicating the best alternative for producers.O objetivo deste trabalho foi avaliar a influência de dois métodos de poda e a ausência desta no desenvolvimento vegetativo e produtivo e na qualidade dos frutos de noz-pecã em um pomar de alta densidade. O experimento foi conduzido com a cultivar Melhorada em um pomar comercial de nogueira-pecã no município de Santa Rosa, Rio Grande do Sul (RS), Brasil. O estudo foi realizado entre julho de 2018 e junho de 2020. Em delineamento de blocos casualizados, foram aplicados os seguintes tratamentos: sem poda, poda hedge e poda central. A poda hedge aumentou o crescimento dos ramos, enquanto a poda central diminuiu o número de ramos secos. A produção de frutos oscilou nos ciclos. No primeiro, a produção foi superior quando se realizou a poda central. No segundo ciclo, foi superior nas árvores não podadas. Embora ambos os métodos de poda tenham diminuído o número de frutos com epicarpos fechados, não afetaram a maioria das variáveis de qualidade dos frutos. Portanto, os resultados demonstram que os métodos de poda promovem o desenvolvimento vegetativo das nogueiras, reduzindo os ramos secos, mas são inconclusivos quanto à sua produção e não têm efeito significativo sobre as principais variáveis da qualidade dos frutos. A avaliação e continuidade da poda por mais ciclos é importante para se obter resultados mais consistentes para indicar a melhor alternativa para os produtores.
 
Outcrossing and heterozygosity rates in tropical onion populations
Get PDFOutcrossing and heterogosity rates are important for defining genetic conservation and breeding strategies, and these estimates are quite rare to onion. The aim of this study was to estimate cross-pollination and heterozygosity rates in tropical onion populations to guide development of new varieties. Eight tropical onion pairs were field isolated to be open pollination by insects. Parents vernalized bulbs were used for pair crossing, in alternate rows, 1:1. Seeds were harvested from the female parent to assess the progenies outcrossing and heterogigosity rates based on color of the red bulb, partially dominant over yellow, and four microsatellite loci. The outcrossing rates estimated with morphological marker, in the ‘BRS Rio Vale’ × ‘BRS Carrancas’, ‘Botucatu’ × ‘BRS Carrancas’, ‘IPA 11’ × ‘IPA 10’ and ‘BRS Alfa São Francisco’ × ‘IPA10’ crosses, ranged from 15% to 39%, with an average of 28.2%, while with microsatellite loci, in the ‘BRS Alfa São Francisco’×’IPA 11’, ‘Alfa SF RT’ × ‘BRS A. São Francisco’, ‘BRS Rio Vale’ × ‘Botucatu’ and ‘Cascuda T6’ × ‘Botucatu’ crosses, ranged from 33% to 71%, with an average of 42.7%, indicating a mixture of cross-pollination and self-pollination within progenies. The average values of heterozygosity in the eight populations ranged from 0.82 to 1.0, indicating the possibility of developing open pollinated onion varieties with greater adaptation to biotic and abiotic stresses.Outcrossing and heterogosity rates are important for defining genetic conservation and breeding strategies, and these estimates are quite rare to onion. The aim of this study was to estimate cross-pollination and heterozygosity rates in tropical onion populations to guide development of new varieties. Eight tropical onion pairs were field isolated to be open pollination by insects. Parents vernalized bulbs were used for pair crossing, in alternate rows, 1:1. Seeds were harvested from the female parent to assess the progenies outcrossing and heterogigosity rates based on color of the red bulb, partially dominant over yellow, and four microsatellite loci. The outcrossing rates estimated with morphological marker, in the ‘BRS Rio Vale’ × ‘BRS Carrancas’, ‘Botucatu’ × ‘BRS Carrancas’, ‘IPA 11’ × ‘IPA 10’ and ‘BRS Alfa São Francisco’ × ‘IPA10’ crosses, ranged from 15% to 39%, with an average of 28.2%, while with microsatellite loci, in the ‘BRS Alfa São Francisco’×’IPA 11’, ‘Alfa SF RT’ × ‘BRS A. São Francisco’, ‘BRS Rio Vale’ × ‘Botucatu’ and ‘Cascuda T6’ × ‘Botucatu’ crosses, ranged from 33% to 71%, with an average of 42.7%, indicating a mixture of cross-pollination and self-pollination within progenies. The average values of heterozygosity in the eight populations ranged from 0.82 to 1.0, indicating the possibility of developing open pollinated onion varieties with greater adaptation to biotic and abiotic stresses
Taxa de crescimento, índice de área foliar e produtividade de jambu cultivado em sistema hidropônico
No full textThe jambu (Spilanthes oleracea L.) is a leafy vegetable with medicinal characteristics, where it is used for various purposes, whether food, cosmetics or medicinal. The work aimed to carry out the growth analysis in jambu plants, grown in hydroponic system. The experiments were conducted at the company B&A Hidroponia, in a hydroponic cultivation system NFT, in a protected environment. The experimental design used was completely randomized with six treatments and three replications. Morphophysiological indices, culture growth rate, relative growth rate, net assimilation rate and productivity were analyzed. Crecism analysis showed that the jambu plant in a hydroponic system has higher morphophysiological indexes after the 39-day cycle and was directly influenced by the liquid assimilation rate (TAL), which is influenced by the duration of the leaf area (DAF), the producer must pay attention to the handling of the nutrient solution. And a productivity of 11.39 Kg / m2 at 54 DAS of cultivation in hydroponics.O jambu (Spilanthes oleracea L.) é uma hortaliça folhosa com características medicinais, onde é utilizada para diversos fins, sejam alimentícios, cosméticos ou medicinais. O trabalho objetivou-se em realizar a análise de crescimento em plantas de jambu, cultivadas em sistema hidropônico. Os experimentos foram conduzidos no sitio da empresa B&A Hidroponia, em sistema de cultivo hidropônico NFT, em ambiente protegido. O delineamento experimental utilizado foi o inteiramente casualizado com seis tratamentos e três repetições. Foram analisados indices morofofisiologicos, taxa de crescimento da cultura, taxa de crescimento relativo, taxa assimilatória liquida e produtividade. Á analise de crecismento expressou que a planta de jambu em sistema hidroponico apresenta maiores índices de morfofisiológicos a partir do 39 dias de ciclo e foi diretamente influenciado pela taxa de assimilação liquida (TAL), sendo esta influenciada pela duração de área foliar (DAF), devendo o produtor ficar atento ao manejo da solução nutritiva. E uma produtividade de 11,39 Kg/m2 aos 54 DAS de culivo na hidroponia
Eucalyptus shading and allelopathy in the germination and development of pitaya (Hylocereusundatus)
Get PDFEucalyptus spp. it is known to be part of most forests planted for commercial use in Brazil, however when intercropped with Pitaia (Hylocereus undatus), few studies report this interaction. The objective of this work was to evaluate the effects of shading and the existence of allelopathic interaction between Eucalyptus spp and pitaia (H. undatus) in the field, as well as the action of eucalyptus leaf extract in the germination of pitaia seeds in laboratory conditions. In the field experiment, the statistical model of randomized block design (DBC) was used, with the use of adult plants of pitaia and eucalyptus, evaluating the following variables: number of shoots in the aerial part; number of flowers; crown diameter; circumference of the cladode; number of fruits and the variation in the amount of light reaching the plants. It was observed that the plants that were outside the eucalyptus forest showed better results. In the second experiment, the allelopathic action of different concentrations of aqueous extracts of eucalyptus leaves on the germination of pitaia seeds was evaluated. This experiment was carried out in DIC with four repetitions of 60 pitaia seeds. These seeds were then subjected to treatments with different dilutions, varying from 0% (control), 12.5%, 25% and 50% of the stock solution. It was observed that as the leaf extract concentrations increased, germination decreased. The concentrations of 0% (control) and 12.5% showed better results. In conclusion, in fact, eucalyptus exerted an allelopathic action on pitaia plants.Eucalyptus spp. it is known to be part of most forests planted for commercial use in Brazil, however when intercropped with Pitaia (Hylocereus undatus), few studies report this interaction. The objective of this work was to evaluate the effects of shading and the existence of allelopathic interaction between Eucalyptus spp and pitaia (H. undatus) in the field, as well as the action of eucalyptus leaf extract in the germination of pitaia seeds in laboratory conditions. In the field experiment, the statistical model of randomized block design (DBC) was used, with the use of adult plants of pitaia and eucalyptus, evaluating the following variables: number of shoots in the aerial part; number of flowers; crown diameter; circumference of the cladode; number of fruits and the variation in the amount of light reaching the plants. It was observed that the plants that were outside the eucalyptus forest showed better results. In the second experiment, the allelopathic action of different concentrations of aqueous extracts of eucalyptus leaves on the germination of pitaia seeds was evaluated. This experiment was carried out in DIC with four repetitions of 60 pitaia seeds. These seeds were then subjected to treatments with different dilutions, varying from 0% (control), 12.5%, 25% and 50% of the stock solution. It was observed that as the leaf extract concentrations increased, germination decreased. The concentrations of 0% (control) and 12.5% showed better results. In conclusion, in fact, eucalyptus exerted an allelopathic action on pitaia plants
Ferramentas de agricultura de precisão para o manejo da calagem em pomares de mangueira no semiárido brasileiro
No full textOptimizing the recommendation for the management of Liming Demand (LD) is essential for cost reduction and increased yield mango. Therefore, the objective of this study was to delimit management zones for the limestone recommendation in areas of irrigated mango in the Brazilian semiarid using precision agriculture techniques. The experiment was carried out in three commercial mango orchards located in the region of the San Francisco Valley, Brazil. Soil samples were collected in 0.0-0.2 m and 0.2-0.4 m depths following regular grids where the number of samples varied from 50 to 56. Soil analyses were performed. The kriging and inverse distance weighting method were used to interpolated the maps. The LD map was performed from the potential cation exchange capacity (T) and bases saturation (BS) maps. It was verified that the Mandacaru area obtained 63.42% of the field requiring liming, being subdivided into four management zones. The Sempre Verde area obtained 1.20% of the area requiring liming and the Barreiro de Santa Fé area did not present a need for the LD map. The use of precision farming techniques to delineate management zones was adequate to separate the areas into smaller and more homogeneous zones, for a more precise recommendation of liming demand.A otimização da recomendação para o manejo da necessidade de calagem (NC) é essencial para redução de custos e aumento da produção da cultura da mangueira. Portanto, o objetivo deste estudo foi delimitar zonas de manejo para a recomendação de calcário em áreas de mangueira irrigada no semiárido brasileiro, utilizando técnicas de agricultura de precisão. O experimento foi conduzido em três áreas comerciais de mangueira irrigada localizadas na região do Vale do São Francisco, Brasil. Amostras de solo foram coletadas nas camadas de 0,0-0,2 e 0,2-0,4 m de profundidade, seguindo grade regulares, em que o número de amostras variou de 50 a 56. Análises de solo foram realizadas. Os métodos de krigagem e inverso do quadrado da distância foram utilizados para interpolar os mapas. O mapa de NC foi confeccionado a partir do mapas de capacidade de troca de cátions potencial (T) e saturação por bases (V%). Verificou-se que a área Mandacaru obteve 63,42% da área necessitando de calagem, sendo subdividida em quatro zonas de manejo. A área Sempre Verde obteve 1,20% da área necessitando de calagem e a área de Barreiro de Santa Fé não apresentou necessidade do mapa de NC. O uso de técnicas de agricultura de precisão para delimitar zonas de manejo foi adequado para separar as áreas em zonas menores e mais homogêneas, para uma recomendação mais precisa da necessidade de calagem
Production of clonal seedlings of black pepper cv. Bragantina under doses of controlled-release fertilizer
Get PDFCommercial substrates and their fertilization are essential for the morphophysiological, nutritional, and sanitary quality of seedlings. In this perspective, this study aimed to evaluate the quality of clonal seedlings of the black pepper cultivar Bragantina under doses of controlled-release fertilizers (CLF) in a commercial substrate. The treatments were constituted by five doses of the CLF Osmocote® 19-06-10 Mini Prill (3-4 months) (0, 2, 4, 6, and 8 kg m-3), with four replications of 16 cuttings. The CLF Osmocote®, especially in doses close to 4.16 kg m-3, showed to be promising for the production of clonal seedlings of the black pepper cultivar Bragantina.Commercial substrates and their fertilization are essential for the morphophysiological, nutritional, and sanitary quality of seedlings. In this perspective, this study aimed to evaluate the quality of clonal seedlings of the black pepper cultivar Bragantina under doses of controlled-release fertilizers (CLF) in a commercial substrate. The treatments were constituted by five doses of the CLF Osmocote® 19-06-10 Mini Prill (3-4 months) (0, 2, 4, 6, and 8 kg m-3), with four replications of 16 cuttings. The CLF Osmocote®, especially in doses close to 4.16 kg m-3, showed to be promising for the production of clonal seedlings of the black pepper cultivar Bragantina
Growth and production of lettuce on substrates based on detritivorous earthworms drilocomposts
No full textAlternative plant growing inputs have been increasingly sought out to reduce the economic-environmental impacts of intensive use of synthetic fertilizers in conventional agriculture. This study aimed to evaluate the production components of lettuce in response to the use of earthworm compost in substrate compositions. The experiment was carried out in a greenhouse using a completely randomized design in a 3 x 5 factorial scheme, with six replications, testing three earthworm species (Eisenia andrei, Eudrilus eugeniae, and Perionyx excavatus) and five drilocompost ratios (0%, 25%, 50%, 75%, and 100%), produced by these species and added to the composition of substrates by mixing them with soil. Production components evaluated comprised total and commercial numbers of leaves, commercial fresh weight, as well as shoot and total fresh and dry weights. Lettuce production components increased as the drilocompost ratio in substrates was raised, regardless of the earthworm species. Moreover, the addition of 25% this drilocomposted material in the dystrophic soil was enough to improve its fertility condition. In general, substrates prepared with worm castings from Perionyx excavatus and Eudrilus eugeniae were more efficient in increasing lettuce production components than that from Eisenia andrei.Alternative plant growing inputs have been increasingly sought out to reduce the economic-environmental impacts of intensive use of synthetic fertilizers in conventional agriculture. This study aimed to evaluate the production components of lettuce in response to the use of earthworm compost in substrate compositions. The experiment was carried out in a greenhouse using a completely randomized design in a 3 x 5 factorial scheme, with six replications, testing three earthworm species (Eisenia andrei, Eudrilus eugeniae, and Perionyx excavatus) and five drilocompost ratios (0%, 25%, 50%, 75%, and 100%), produced by these species and added to the composition of substrates by mixing them with soil. Production components evaluated comprised total and commercial numbers of leaves, commercial fresh weight, as well as shoot and total fresh and dry weights. Lettuce production components increased as the drilocompost ratio in substrates was raised, regardless of the earthworm species. Moreover, the addition of 25% this drilocomposted material in the dystrophic soil was enough to improve its fertility condition. In general, substrates prepared with worm castings from Perionyx excavatus and Eudrilus eugeniae were more efficient in increasing lettuce production components than that from Eisenia andrei.
Palavras-chave: Cultivo orgânico, Eisenia andrei, Eudrilus eugeniae, Lactuca sativa, Perionyx excavatus
Estimation of Thunbergia grandiflora leaf area from allometric models
Get PDFSky vine (Thunbergia grandiflora Roxb) is a vine with important structural components for forest environments. Studies on growth and development are necessary, because of the environmental and economic importance. The leaf area determination is essential for ecophysiological studies to understand the relationship of the plant with the environment. The objective of this work was to estimate an allometric equation to estimate the leaf area of T. grandiflora from linear dimensions. 200 leaves of different shapes and sizes were collected from adult plants and the length (L), width (W), the product between length and width (LW), and real leaf area (LA) were measured. The linear regression, linear without intercept, quadratic, cubic, power, and exponential models were used to estimate the equations. The criteria for determining the best model were higher determination coefficient (R2), Willmott\u27s agreement index (d), lower Akaike information criterion (AIC), the root of the mean error square (RMSE), and BIAS index closer to zero. The leaf area of T. grandiflora can be estimated satisfactorily by the equation ŷ = 0.58*LW.Sky vine (Thunbergia grandiflora Roxb) é uma planta trepadeira com importantes componentes estruturais para ambientes florestais. Estudos sobre crescimento e desenvolvimento são necessários, devido à importância ambiental e econômica. A determinação da área foliar é essencial para estudos ecofisiológicos para entender a relação da planta com o meio ambiente. O objetivo deste trabalho foi estimar uma equação alométrica para estimar a área foliar de T. grandiflora a partir de dimensões lineares. 200 folhas de diferentes formas e tamanhos foram coletadas de plantas adultas e o comprimento (L), largura (W), o produto entre comprimento e largura (LW) e área foliar real (LA) foram medidos. Os modelos de regressão linear, linear sem intercepto, quadrático, cúbico, potência e exponencial foram usados para estimar as equações. Os critérios para determinar o melhor modelo foram maior coeficiente de determinação (R2), índice de concordância de Willmott (d), menor critério de informação de Akaike (AIC), raiz do quadrado do erro médio (RMSE) e índice BIAS mais próximo de zero. A área foliar de T. grandiflora pode ser estimada de forma satisfatória pela equação ŷ = 0,58*LW
Hydrogen peroxide as a mitigator of salt stress for melon seed germination
Get PDFThe effect of hydrogen peroxide has been very studied, but little is known on its effect on seed germination and initial growth of melon trees under salt stress. In this context, the objective of this work was to evaluate the effect of hydrogen peroxide as a mitigator of salt stress on melon seed germination. The experiment was conducted in the Laboratory of Seeds and Seedlings of the Federal University of Campina Grande, in Pombal, PB, Brazil. A completely randomized design was used, in a 4×6 factorial arrangement consisting of times of seed imbibition in H2O2 (0, 8, 16, and 24 hours) and irrigation water salinity levels (0.3, 1.2, 2.1, 3.0, 3.9, and 4.8 dS m-1), with four replications. Melon seeds of the commercial variety Imperial-45 were used. The H2O2 solution was prepared from a 1 mmol L-1 H2O2 solution, which was diluted to reach the concentration of 10 μmol L-1. The seeds were placed in a beaker and subjected to imbibition with 100 ml of the solution for the different times studied. The variables evaluated were: germination percentage, first germination counting, germination speed index, mean germination speed, mean germination time, and radicle length. The of H2O2 solution to seeds for 16 hours mitigates the negative effects caused by salt stresses by up to 2.2 dS m-1; however, the application of H2O2 solution for 24 hours is harmful to the germination process of melon seeds.O efeito do peróxido de hidrogênio vem sendo muito estudado, mas pouco se sabe sobre o seu efeito na germinação e crescimento inicial de sementes de meloeiro submetidas ao estresse salino. Neste contexto, objetivou-se avaliar o efeito do peróxido de hidrogênio como atenuante do estresse salino na germinação das sementes de meloeiro. O trabalho foi realizado no Laboratório de Sementes e Mudas da Universidade Federal de Campina Grande, campus Pombal-PB. O experimento foi conduzido em delineamento inteiramente casualizado, em esquema fatorial 4 x 6, tempos de embebição no H 2 O 2 (TE 1 : 0; TE 2 : 8; TE 3 : 16 e TE 4: 24 horas) e níveis de salinidade da água de irrigação (0,3; 1,2; 2,1; 3,0; 3,9 e 4,8 dS m -1 ), com quatro repetições. Foram utilizadas sementes de meloeiro da variedade comercial Imperial-45. A solução foi preparada a partir de uma solução a 1mmol L -1 de H 2 O 2 , sendo diluída para atingir a concentração de 10 µmol L -1 , posteriormente como sementes foram acondicionadas em becker e embebidas com 100 ml da solução por diferentes tempos . As variáveis avaliadas foram: porcentagem de germinação, primeira contagem de germinação, índice de velocidade de germinação, velocidade média de germinação, tempo médio de germinação e comprimento da radícula. Sementes embebidas em solução de H 2 O2 por 16 horas atenuam os efeitos causados pelo estresse salino em até 2,2 dS m -1 , porém quando embebidas por 24 horas na solução de H 2 O 2 causaram prejuízos no processo germinativo das sementes meloeiro
Dispersão de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) em cultivos de couve e repolho
No full textParasitoids of the Trichogramma genus are used worldwide for pest management. The ability to disperse these insects in crops determines the number of release points necessary for there to be satisfactory results in terms of parasitism and, consequently, pest management. To determine the dispersal capacity of T. pretiosum in cabbage and cabbage crops, 26 x 26 m areas were demarcated, in which cards containing A. kuehniella eggs were placed, distributed in a concentric and equidistant manner. In the center of each area, 100,000 parasitoids were released and parasitism was allowed for 24 hours. The experimental design used was in randomized blocks, with five treatments (distance) and four replications. The average dispersed distance was 6.27 meters in cabbage and 6.07 in cabbage, while the dispersion area was 81.23 in cabbage cultivation and 79.03 meters in cabbage cultivation. 123 release points required for kale and 126 for cabbage.Parasitoides do gênero Trichogramma são utilizados em todo o mundo para o manejo de pragas. A capacidade de dispersão desses insetos em cultivos determina o número de pontos necessários de liberação para que haja resultados satisfatórios quanto ao parasitismo e consequentemente, o manejo da praga. Para determinação da capacidade de dispersão de T. pretiosum em cultivos de couve e repolho, foram demarcadas áreas de 26 x 26 m, em que foram colocadas cartelas contendo ovos de A. kuehniella distribuídas de forma concêntricas e equidistantes. No centro de cada área foram liberados 100 mil parasitoides e o parasitismo foi permitido por 24 horas. O delineamento experimental utilizado foi em blocos casualizados, com cinco tratamentos (distância) e quatro repetições. A distância média dispersada foi de 6,27 metros em couve e 6,07 em repolho, enquanto que área de dispersão foi de 81,23 na cultura da couve e 79,03 metros no cultivo de repolho, sendo possível determinar que por hectare são necessários 123 pontos de liberação para couve e 126 para repolho