Cotton response to mepiquat chloride and temperature

Gibberellin inhibitor growth regulators are used for cotton (Gossypium hirsutum L.) canopy manipulation to avoid excess growth and yield losses. However, under temperatures below or over the optimum for cotton production the effect of mepiquat chloride (MC) has not always been significant. In this experiment, cotton plants were grown in growth chambers to study the response to MC as affected by temperature and to determine if an increase in dose could overcome the temperature effects. Mepiquat chloride was applied at rates of 0, 15 and 30 g ai ha-1 at the pinhead square stage. Plants were then grown under three temperature regimes: 25/15 °C, 32/22 °C, and 39/29 °C (day/night temperatures) for 51 days. Higher temperatures increased plant height, reproductive branches, fruit number, fruit abscission, and photosynthesis per unit area, but decreased leaf area and chlorophyll. The largest effect of MC on plant height was observed when the daily temperature was 32 °C, with nights of 22 °C, which was also best for plant growth. High temperatures not only decreased the effectiveness of MC on plant height control, but also caused lower dry matter and fruit number per plant. Low temperatures (25/15 ºC) decreased cotton growth and fruit retention, but a higher concentration of MC was required per unit of growth reduction as compared with 32/22 ºC. At high temperatures, the rate of MC to be applied must be disproportionately increased, because either plant growth is impaired by high temperature lessening the effect of MC, or degradation of MC within the plant is too rapid.

População microbiana total e solubilizadora de fosfato em solo submetido a diferentes sistemas de cultivo

O objetivo deste trabalho foi avaliar o efeito de diferentes espécies de plantas, fontes de fósforo e calagem sobre a população microbiana total e solubilizadora de fosfato. Foram isolados fungos e bactérias capazes de solubilizar hidroxiapatita, proporcionando P solúvel. O experimento utilizado foi em blocos ao acaso com fatorial 3x3x2. E os fatores avaliados foram espécies de plantas (controle, braquiária e guandu), fertilizantes (controle, superfosfato simples e fosfato de rocha, ambos na dose de 400 kg ha-1 de P(2)0(5) ) e calagem (com e sem calcário). A população bacteriana cresceu pelo efeito da calagem, e a de fungos aumentou, independentemente da calagem, nas parcelas cultivadas com braquiária e fertilizadas com superfosfato. Foi constatado incremento de biomassa-P microbiana sobre o controle por influência da braquiária (23,9%), do superfosfato (30,9%) e da calagem (46,9%). O número de bactérias solubilizadoras foi favorecido pela calagem ou pelo plantio de guandu adubado com fosfato natural ou com braquiária sem adubação. Os fungos solubilizadores aumentaram na ausência de planta ou de adubação e na presença de guandu com fosfato natural. Finalmente, a calagem favoreceumais o crescimento dos fungos solubilizadores, em comparação com o controle, nos tratamentos fosfato natural, braquiária ou guandu.

Nematofauna fitopatogênica de sementes comerciais de forrageiras tropicais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Qualidade da água para a irrigação de plantas em viveiros: utilização de descargas elétricas sem efeito térmico e de campos de energia no controle de Meloidogyne incognita Raça 1

The effect of electrical discharges without thermic effect and of energy field on Meloidogyne incognita Rara 1 larvae elimination in weir water was tested. on an average, 63,22% of larvae were killed by electrical discharges, in comparison with 53,12% of dead larvae in the control (water that received only ammonium sulphate) as an electrolyte. Water exposed to energy fields presented higher percentages of dead larvae (50,01% for electromagnetic field, 43,78% for variable electric field and 40,48% for static electric field) in comparison with control, represented by water without exposition to any energy field and without ammonium sulphate (34,27%).

Utilização de polímero hidroabsorvente no meloeiro (Cucumis melon L.) sob diferentes lâminas de irrigação

This work was carried out to evaluate the use of a hydrogel polymer in melon crop under different irrigation depths, with the objective of improve water retention, and efficiency of water and nutrient utilization by plants. One trial consisted of two treatments with four replications: a treatment with irrigation depth corresponding to 75% of gross depth and 27g of the soil conditioner per plant; the control with irrigation depth equal to the gross depth and without conditioner. The following characteristics were evaluated: root length, yield and quality of melon fruits. Root growth was bigger in the plants where soil conditioner was used. Use of soil conditioner provided an increase on melon yield and number of fruits per linear meter. Mean fruit weight and total soluble solids were not influenced by soil conditioner application and irrigation depth reduction.

Eucalyptus ESTs associated with resistance to herbicide inhibitors of aromatic and branched-chain amino acid synthesis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito da chuva sobre a ação do herbicida imazapyr no controle de plantas daninhas aquáticas

The aim of this study was to evaluate the influence of different periods of rainfall that occurred after the application of the imazapyr herbicide on the control efficiency of Pistia stratiotes and Eichhornia crassipes. We studied 10 mm rainfall, applied for 5' at different time periods (0h, 2h, 4h, 6h, 8h, 12h, 24h, not simulated rainfall) after the application of imazapyr formulation Arsenal NA, 250 g ai ha -1 (1.0 L cp ha -1). The experiment had completely randomized design with four replications. Plants were evaluated at 7, 14, 21, 28 and 35 days after application (DAA), and the results submitted to analysis of variance by F test and treatment means compared by Tukey's test (p <0. 05). The occurrence of rainfall up to 6 hours after herbicide application, plants of P. stratiotes, negatively affected its efficiency and control; rainfall intervals over 8 hours had no effect in control. The occurrence of rainfall at all time intervals did not affect the control of E. crassipes plants.

Projeto e simulação de um sistema de controle via LMIs da produção de vapor de uma caldeira aquatubular

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Controle químico de nematoides em canaviais implantados com Tecnologia Plene

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Um sistema de apoio a decisão utilizado no planejamento e controle de produção de uma empresa aeronaútica: Reinaldo de Almeida. -

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da indução de resistência no controle do crestamento bacteriano comum do feijão vagem

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ação de indutores bióticos e abióticos no controle da ferrugem do eucalipto, atividade enzimática e expressão gênica durante o processo de infecção

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influência do volume reduzido e do estádio fenológico da planta de soja no controle da Anticarsia gemmatalis (Hübner, 1818)

Pós-graduação em Agronomia (Entomologia Agrícola) - FCAV

Controle de qualidade e obtenção de extratos de espécies vegetais do cerrado brasileiro com potencial etnofarmacológico

ANVISA (National Health Surveillance Agency) has published in recent years, laws that regulate the stages of the control of plants derivatives, including tests of macro and microscopic botanical identification, phytochemical determination, tests of authenticity and purity, microbiological testing, among other parameters. All the analytical procedures of plant drugs control required by law must be based on the Brazilian Pharmacopoeia, other Pharmacopoeias recognized by ANVISA or quality control guides of plant species published by the World Health Organization (WHO). This study aimed to evaluate some pharmacognostic, phytochemical screening and microbiological control of plant species of the Brazilian cerrado, which have indicated ethnopharmacological: Byrsonima intermedia (Bi), Bauhinia holophylla (Bh) and Myrcia bella (Mb). In addition, certain parameters were determined for obtaining extracts from plants sprayed and dried. These data are important to obtain new scientific information from Brazilian plants with therapeutic potential.

Eficiência da calda bordaleza e sulfocálcica em diferentes concentrações e idade de planta no controle de doenças foliares de maracujá-doce em cultivo orgânico

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)