Interferência de plantas daninhas na cultura do quiabo ... ABSTRACT -An experiment was carried out under field conditions in Médio Vale do Rio Doce-MG, from May to October, 2007, to establish periods of weed interference in Abelmoschus esculentus crop. 'Santa Cruz-47' seeds were sown in a 0.25 x 1.0 m spacing, and weed control times varied from 0 to 120 days after emergence (DAE). Number of fruit per plant and yield as well as values in days for Period Previous to Interference (PPI), Critical Prevention Period of Interference (CPPI) and Total Period of Interference Prevention (TPIP) were determined, considering 5% loss. Plants from the species studied were placed in the plots, isolated or in competition with A. esculentus, aiming to to evaluate the competitive capacity of the main weeds. Area, number of leaves and plant height of A. esculentus were evaluated.Yield and number of fruit presented a similar behavior. The estimated PPI was 25 days, indicating when to start weed control. The CPPI observed was 75 days, indicating 100 days for TPIP. Among the weeds evaluated, Eleusine indica showed the highest competitive capacity against the the crop.

RESUMO -Os solos do Estado do Espírito Santo apresentam baixa fertilidade natural, que frequentemente limita a produção das lavouras devido às deficiências de alguns elementos. No entanto, os mesmos apresentam alto potencial de produção agrícola quando são sanadas as limitações químicas presentes. Objetivou-se no presente estudo descrever a variabilidade espacial dos macronutrientes cálcio (Ca), magnésio (Mg), fósforo (P) e potássio (K) em uma lavoura de café conilon (Coffea canephora Pierre) localizada na área rural do município de São Mateus, ES. O experimento foi conduzido em uma lavoura, plantada com espaçamento 1,8 x 1,0 m (5.555 plantas ha ABSTRACT -The soils in the state of Espírito Santo, Brazil (ES) display low natural fertility, which often limits the production of the crops due to the deficiency of some elements. However, they have a high potential for agricultural production when the chemical limitations which are present are overcome. The aim of this study was to describe the spatial variability of the macronutrients calcium (Ca), magnesium (Mg), phosphorus (P) and potassium (K) in a crop of conilon coffee (Coffea canephora Pierre) located in the rural area of the city of São Mateus, ES. The experiment was carried out on a crop, planted at a spacing of 1.8 x 1.0 m (5,555 plants ha -1 ). A rectangular grid of 61.6 x 20.0 m (1,232 m 2 ) was considered, with 60 sampling points, spaced 5.6 m apart between rows and 5.0 m within each crop row. At each point in the sampling grid, soil samples were collected at a depth of 0.00-0.20 m. All the macronutrients under study displayed a strong spatial dependence. The greatest range of spatial dependence was observed for Mg (32.4 m) and the smallest for Ca (8.1 m). Study of the spatial variability of the chemical properties of the soil by geostatistics, using kriging, proved to be an important tool in understanding the spatial distribution of macronutrients in the soil, and may be crucial in aiding the decision making that helps to attend the nutritional requirements of the conilon coffee crop.

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Resumo -A pimenta-do-reino é o condimento mais comercializado no mundo e uma cultura de importância sócio econômico regional. A fusariose é uma doença causada pelo fungo Fusarium solani f. sp. piperis (Nectria haematococca f. sp. piperis) e tornou-se o principal problema fitossanitário da pipericultura nacional. Pouco se conhece da dinâmica de suas interações com o ambiente do solo, hospedeiro e estabelecimento da doença. A geoestatística possui ferramentas que permitem conhecer e visualizar a variabilidade espacial, além de correlacionar e associar o mesmo aos fenômenos em estudo, contribuindo para o entendimento das interações patógeno-ambiente-hospedeiro. Sendo assim, o objetivo foi pesquisar e aplicar métodos da geoestatística para compreender a distribuição espacial da fusariose em pimenta-doreino. O experimento foi conduzido no período de 2010 a 2011, na Região Norte do Estado do Espírito Santo. A geoestatistica foi utilizada para constar a dependência espacial das variáveis em estudo, para isso implantou-se uma malha amostral regular de 12.000m 2 e a incidência da doença foi avaliada ao longo de 150 dias. Os mapas da distribuição da doença ao longo do tempo demostraram foco inicial nas bordas da lavoura e os modelos teóricos ajustados dos variogramas, representaram os diferentes estágios da epidemia de fusariose na lavoura de pimenta-do-reino.Palavras-chave: geoestatística; Fusarium solani f. sp. piperis; Piper nigrum L. Spatial and Temporal Distribution of fusarium wilt in Black Pepper CropAbstract -The Fusarium wilt is a disease caused by the fungus Fusarium solani f. sp. piperis (Nectria haematococca f. sp. piperis) and became the main disease problem of national pepper crop. Few reports is known about the dynamics of their interactions with the soil environment, host and disease establishment. Geostatistics provides tools that allow understanding and visualizing the spatial variability, to correlate and to associate it with the phenomena under study, contributing to the understanding of interactions between pathogen-host-environment. Therefore, the present experiment was to investigate and to implement geostatistics methods to understand the spatial distribution of fusarium wilt in black pepper. The experiment was conducted from 2010 to 2011 in the North of Espirito Santo State. Geostatistics was used to include the spatial dependence of the variables under study, for it was implemented a regular sampling grid (12.000m 2 ) and the disease incidence was evaluated over 150 days, a total of seven evaluations. In the last evaluation were carried out soil samples for chemical,, physical and textural analysis. The maps of disease distribution over time demonstrated an initial focus on the edges of the crop and theoretical models of the adjusted variogram represented the different stages of the epidemic of Fusarium in the black pepper crop.Key words: geostatistics; Fusarium solani f. sp. piperis; Piper nigrum L. IntroduçãoA análise espacial das doenças de plantas ao longo do tempo permite caracterizar o padr...

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