Mário José Pedro Júnior

Escala para avaliação de estádios fenológicos do cafeeiro arábica

A scale to evaluate coffee phenological stages is proposed based on images of twelve stages, considering lot for reproductive period, from dormant buds up to dry beans (harvest). During the growing season 2001/02 the scale was used for different coffee cultivars in field trials located at Campinas and Mococa, Sao Paulo State, Brazil. The scale showed to be useful to relate meteorological variation and crop yield, development and maturation period for the different evaluated cultivars.

Risk analysis of climate change on coffee nematodes and leaf miner in Brazil

The objective of this work was to assess the potential impact of climate change on the spatial distribution of coffee nematodes (races of Meloidogyne incognita) and leaf miner (Leucoptera coffeella), using a Geographic Information System. Assessment of the impacts of climate change on pest infestations and disease epidemics in crops is needed as a basis for revising management practices to minimize crop losses as climatic conditions shift. Future scenarios focused on the decades of the 2020s, 2050s, and 2080s (scenarios A2 and B2) were obtained from five General Circulation Models available on Data Distribution Centre from Intergovernmental Panel on Climate Change. Geographic distribution maps were prepared using models to predict the number of generations of the nematodes and leaf miner. Maps obtained in scenario A2 allowed prediction of an increased infestation of the nematode and of the pest, due to greater number of generations per month, than occurred under the climatological normal from 1961-1990. The number of generations also increased in the B2 scenario, but was lower than in the A2 scenario for both organisms.

Estimativa de horas de frio abaixo de 7 e de 13°C para regionalização da fruticultura de clima temperado no estado de São Paulo

Estimativa e mapeamento do numero de horas com temperaturas abaixo de 7 e 13°C no Estado de Sao Paulo e analise comparativa do comportamento de fruteiras de clima temperado constituem os objetivos do presente trabalho. Foi cotado o numero de horas com temperaturas inferiores a 7 e 13°C, indices considerados limites necessarios a dormencia dessas plantas. Foram selecionados termogramas de doze postos agrometeorologicos do Instituto Agronomico, situados em altitudes variaveis entre 25 e 1.000m, correspondentes ao periodo 1964-1973. Estabeleceram-se equacoes para estimativa do numero de horas com temperaturas inferiores a 7°C (HF-7) e 13°C (HF-13) em funcao da temperatura media do mes de julho, cujos coeficientes de correlacao foram de -0,88 e -0,93, respectivamente. Com base nessas equacoes foram mapeadas as isolinhas de HF-7 e HF-13 para o Estado de Sao Paulo, encontrando-se desde valores medios anuais de HF-7 inferiores a 20 horas, caracteristicos das regioes de transicao de clima mesotermico a megatermico do Planalto Ocidental e das regioes mais baixas do norte e oeste do Estado, ate valores anuais de HF-7 superiores a 200 horas, caracteristicos das areas acima de 1.500 metros de altitude no Sul do Estado, na serra da Mantiqueira, limitrofe com Minas Gerais, e na serra do Mar, limitrofe com o Rio de Janeiro. Com base na introducao de diferentes frutiferas de clima temperado no Estado de Sao Paulo, verificou-se uma relacao muito grande entre os indices HF-7 e HF-13 mapeados com o comportamento e potencialidade de exploracao comercial.

Exigência térmica do café arábica cv. Mundo Novo no subperíodo florescimento-colheita

Base temperature and heat requirement, using degree-days were evaluated for coffee cv. Mundo Novo. The sum of reference (ETo) and actual (ETr) evapotranspiration were also determined for the flowering-harvest phenological stage, using coffee phenological data for the growing season from 1971 to 2004. A correction factor was proposed for the degree-days sum related to available water on the first eighty days during the beginning of flowering. The obtained values of base temperature and degree-days requirements were, respectively, 10.2oC and 2887 degree-days and 10.5oC and 2761 degree-days when evaluated with and without adjustement for water deficit. The mean value for ETo sum was 761 mm, and for ETr, 689 mm. When considered the sum of ETr during the development of the berries (first 80 days after flowering) was considered the mean values were 721 mm. The correction factor for water deficit improved the determination of base temperature and heat sum for the flowering-harvest stage for Mundo Novo coffee plants.

Determinação da área foliar em videira cultivar Niagara Rosada

Width of leaf blade was closely correlated with leaf area in leaves of grapes cv. Niagara Rosada. It was found that the shape of any leaf was similar to a circle. A short-cut procedure for estimating easily, rapidly and precisely the leaf area was developed. The equation relating leaf area (AF) to width of leaf blade (L) was: AF = 0.85 p (L/2)2.

Balanço de energia em vinhedo de 'Niagara Rosada'

ENERGY BALANCE ON ‘NIAGARA ROSADA’ VINEYARD The energy balance method was used to characterize the hourly variation of the net radiation, latent and sensible fluxes and soil heat flux on a mature vineyard grown at Jundiai, Sao Paulo, Brazil. The grapevines, cv. Niagara Rosada, in the vineyard were wrapped to trellis wires, creating compact hedgerows 2 m apart, 1.7 m height and 0.4 wide, with the foliage 1m above the soil surface. Also, the net and incoming radiation relationships and the partioning of the available energy to the system into latent and heat flux, and soil heat flux were determined for the vineyard. During a sunny day (dry period) the latent heat flux was 44% of the net radiation and the sensible heat flux, 48%. However during a rainy day, the latent heat flux was 86% of the net radiation and the sensible heat flux, 21%. During a sunny day, after the occurrence of rain, the latent and sensible heat fluxes were, respectively, 68% and 29% of the net radiation. The soil heat flux was 5.7 an 1.3% of the net radiation, for bare soil and mulched rows, respectively.

Climatic risk of grape downy mildew (Plasmopara viticola) for the State of São Paulo, Brazil

Viticulture in Brazil has been growing in importance in recent years. In the State of Sao Paulo, a significant percentage of the production is basically destined to in natura consumption and, more recently, much effort has been made by institutions to revitalize the viticulture in the State. Among fungal diseases, the downy mildew (Plasmopara viticola) is one of the main diseases affecting this crop in Brazil, with extreme damage effects on its production. The objective of this study was to estimate the incidence of the downy mildew on grape under the climatic conditions of the State of Sao Paulo, based on a mathematical model and using Geographical Information System - GIS tools. The study considered the months from September to April, a period in which the downy mildew can affect grapevines under development. Mean temperature and relative humidity were the basic weather data entered in the GIS database. Leaf wetness duration was estimated from relative humidity measurements. Climatic data entered in the GIS were used to calculate and produce maps depicting the severity of the grape downy mildew, through the application of a disease model. Three cities were evaluated (Jales, Jundiai, and Sao Miguel Arcanjo), since they represent the main vineyard centers in the State. The adopted methodology permitted quantifying the severity of the grape downy mildew not only in spatial terms, identifying the variability among the different regions of the State, but also in temporal terms, along the months, making an adequate distinction of the studied cities.

Época de florescimento e horas de frio para pessegueiros e nectarineiras

Blossom dates for 41 peaches and nectarines accesses from the Active Gene Bank (BAG) of stone fruits were evaluated at Capao Bonito (SP), Brazil. Observations of flowering date (70% of opened flowers) were taken and compared to the chilling hours requirement (NHF) considering 7.2 and 13oC. The NHF was estimated using multiple regression equations based on maximum and minimum temperature. The accesses from the BAG were separated by cluster analysis into four groups for peaches and three for nectarines by cluster analysis. The following peaches accesses: IAC 2485-6, IAC 680-13 and Regis and for nectarine: IAC N 785- 9 showed flowering date before July 10th with NHF less than 40 and 500, below 7.2 and 13oC, respectively. The peach cultivars Eldorado, Diamante, Arlequim, Bolao, and Marli showed blossom dates after August 1st, requiring more than 70 and 650 NHF bellow 7.2 and 13oC, respectively. The main peach cultivars for Sao Paulo State like: Aurora-1, Douradao and Dourado-1, flowered from July 11 to 20 with NHF from 41 to 50 bellow 7.2oC and from 501 to 560 bellow 13oC.

Efeitos de diferentes condições de irrigação e densidade de semeadura no microclima e na ocorrência de helmintosporiose de oídio em trigo

Field experiments (1990 and 1991) were carried out in Campinas, State of Sao Paulo, Brazil, during winter season, in order to study sprinkler irrigation and crop density effects on micrometeorological parameters (average air temperature and dew duration) and to evaluate their influence in the occurrence of spot blotch and powdery mildew in wheat crop. The results obtained were submitted to statistical analysis: comparison of means of two independent sample analysis (microclimate) and confidence interval analysis (infection rates). It was verified that in the most dense and irrigated plots the average air temperatures were lower (0.7°C) and the dew durations (DPM) were longer (45 minutes) than in the other plots. The infection rates of diseases were influenced positively by irrigation and crop density when the macroclimatic conditions were not favorable to disease development.

Estimativa de graus-dia em função de altitude e latitude para o estado de São Paulo

Multiple regression equations were developed to determine the total monthly degree-days in function of altitude (meters) and latitude (minutes), in order to estimate the amount of heat unit for annual crops in localities where meteorological data are not available. The degree-day was determined through thermometric data, using monthly mean values of maximum and minimum temperatures obtained in several meteorological stations of Sao Paulo State. The base temperature of 10° C, below which great part of the crops does not nave a good development was used to determine the heat-units.