Paulo Henrique Caramori

Características fisiológicas e de crescimento de cafeeiro sombreado com guandu e cultivado a pleno sol

The characterization of shade effects on the physiology of coffee is important to determine optimum levels of radiation and temperature, as well as to subsidize studies on growth of shaded plants aiming at determining the ideal coffee plant architecture that maximizes the capture of the available solar radiation in shaded environments. The objective of this work was to evaluate physiological and growth characteristics of coffee (Coffea arabica L.) shaded with pigeonpea (Cajanus cajan (L.) Millsp.) and under full sun. The low level of incident radiation on the coffee shaded with pigeonpea caused decreases in the photosynthetic rate and transpiration, increased plant height and leaf size, but diminished leaf dry matter. These results indicate that the excess of shade drastically affects the physiology and morphology of C. arabica.

Modifications on leaf anatomy of Coffea arabica caused by shade of pigeonpea (Cajanus cajan)

Adaptacoes de plantas da mesma especie aos diferentes habitats, constituem a base da diferenciacao entre folhas a pleno sol e folhas sob sombra e estao associadas a caracteristicas anatomicas distintas. Para caracterizar tais mudancas em cafeeiros cultivados sob sombra de guandu (Cajanus cajan) e a pleno sol, em Londrina, PR, foram realizadas avaliacoes de modificacoes ocorridas na anatomia foliar. As estruturas internas avaliadas foram: parede celular e cuticula; epiderme; mesofilo (parenquima palicadico, parenquima lacunoso e espacos intercelulares) e estomatos. Para todas as variaveis avaliadas observaram-se diferencas anatomicas entre folhas expostas ao sol e a sombra. As folhas expostas ao sol apresentaram cuticulas e paredes celulares mais espessas, celulas da epiderme mais estreitas, parenquima palicadico com celulas mais alongadas, parenquima lacunoso espesso e com poucos espacos intercelulares e maior numero de estomatos. Folhas sob condicoes de denso sombreamento apresentam menor espessamento da cuticula e da parede celular; mesofilos com menores volumes, porem com maiores espacos intercelulares; epidermes com celulas mais espessas e estomatos em menor quantidade, envoltos por celulas subsidiarias de menores dimensoes. Plantas cultivadas a pleno sol apresentam maiores taxas fotossinteticas. Assim, Coffea arabica caracteriza-se como uma especie com grande amplitude de adaptacao fenotipica as mudancas na intensidade de radiacao solar.

Zoneamento agroclimático para o pessegueiro e a nectarineira no Estado do Paraná

ABSTRACT - Peach and nectarine crops, despite their high climatic and market potential, are not yet well exploited in the state ofParana. The objective of this research was to indicate zones with lower climatic risk for production of these crops in the state ofParana, Brazil, using climatic risk analysis and agronomic data. Historical data of 32 weather stations of IAPAR were analyzed toestimate and map the risks of late frost and the average totals of chilling hours above 7.2 o C accumulated from May to September. Theregions in which the last frost occurs before flowering and with the total chilling hours suitable to the cultivars needs were consideredapt. Most of the north, west and the coast of Parana do not have enough chilling hours. The areas located in the south with alt itudesabove 800 m are the most suitable. Within the apt areas eight zones were classified according to the chilling requirements of p eachesand nectarine varieties and climatic conditions of each region: zone 1 (75 to 150 hf); zone 2 (150 to 200 hf); zone 3 (200 to 250 hf); zone4 (250 to 300 hf); zone 5 (300 to 350 hf); zone 6 (350 to 400 hf), zone 7 (400 to 450 hf) and zone 8 (> 450 hf). The zones with lower altitudeand higher temperatures accumulate less chilling hours from May to September and are indicated for cultivars with lower chillingrequirement. The zones with higher altitudes and high chilling accumulation are suitable for varieties with high chilling requi rements(> 400 chilling hours). The last frost is likely to occur in the last ten days of August in the colder regions and do not caus e damagesto suitable varieties of peaches and nectarine. The results obtained in this work support the adoption of policies to foment thesecrops in the state of Parana with low risk.

Tendências na variabilidade climática sazonal e anual das temperaturas máxima e mínima do ar no Estado do Paraná

O presente trabalho teve por objetivo analisar a variabilidade sazonal e anual das temperaturas maxima e minima do ar no Estado do Parana. A Analise de Regressao e o teste de Kendall foram utilizados para testar a tendencia das medias de temperatura maxima e minima, do numero de dias com registros de temperatura inferior a 3 °C, dos eventos extremos e valores absolutos diarios da temperatura maxima e minima nas escalas sazonal (verao, outono, inverno e primavera) e anual. Os pontos de descontinuidade obtidos pelo Teste de Homogeneidade Normal Padrao mostram resultados mais expressivos para a temperatura maxima anual e no outono. Para esta variavel meteorologica os pontos foram obtidos predominantemente no inicio da decada de 2000. Na temperatura maxima anual e, principalmente na temperatura minima, em todas as escalas de tempo, houve tendencia de aumento. Esse aumento relativamente maior da temperatura minima sugere uma diminuicao na amplitude termica no Parana. Os valores dos extremos diarios da temperatura minima estao sendo maiores, porem, menos frequentes. Por outro lado, as temperaturas maximas tem sido mais intensas e frequentes, especialmente na primavera.

Effect of leaf Water potential on cold tolerance of Coffea arabica L.

Young coffee plants from cultivar Mundo Novo of Coffea arabica were grown without irrigation for 32 consecutive days, to evaluate the effect of leaf water potential on damage caused by low temperatures, under controlled conditions. A wide range of leaf water potentials were evaluated, from - 0.45MPa (wet soil) at the beginning of the experimental period, to - 4.8MPa (severe leaf wilting) at the end. Results showed that under moderate water stress, there was a higher frequency of undamaged plants and lower frequency of severely damaged plants. These results help explain part of the regional variability observed after a frost and stress the importance of new studies associating cold and drought tolerance in coffee.

Variabilidade climática sazonal e anual da chuva e veranicos no Estado do Paraná

As mudancas climaticas na escala regional sao muito divergentes e nem sempre acompanham a tendencia global. Metodologias estatisticas foram utilizadas para analisar o comportamento sazonal e anual da chuva e de veranicos, em 21 estacoes hidrologicas localizadas no Estado do Parana. Os resultados obtidos pelo Teste de Homogeneidade Normal Padrao nao indicam pontos de mudancas estatisticamente significativos, no comportamento climatico da quantidade de chuva. Entretanto, a Analise de Regressao e o teste de Kendall mostram que, nas ultimas decadas, a quantidade de chuva anual tem aumentado, principalmente na primavera, entre 16 e 42 mm/decada, na metade leste do Parana. A mesma tendencia foi observada na intensidade dos eventos extremos diarios de chuva, mas os municipios e periodos sazonais com esta caracteristica nao seguem rigorosamente as tendencias apresentadas na quantidade de chuva. O numero de tendencias significativas (predominantemente negativas) e menor para os veranicos, com duracao de 5 a 10 dias, com quantidade acumulada inferior a 10 mm, porem, mais perceptivel na primavera e na escala anual.

Sombreamento de cafeeiros durante o desenvolvimento das gemas florais e seus efeitos sobre a frutificação e produção

The objective of this paper was to evaluate the influence of shading during the period of floral buds development on the growth and maturation of coffee fruits, production and grain size of Coffea arabica L. The experiment was carried out in Londrina, PR, Brazil. Plots of adult coffee plants were shaded monthly in April, May, June, July and August of 2004 using shading screens with 50% of porosity. The coverings were removed simultaneously at the beginning of October of the same year. The interception of 50% of incident radiation over the coffee canopy in different periods of floral buds development did not alter fruit growth and development. Fruit maturation was anticipated due to high temperatures and water deficit, however without significant differences on maturation periods among treatments. Grain yield and size were not affected by shading in the different periods.

Risco de deficiência hídrica na cultura do milho no estado do Paraná

The goal of this work was to determine soil water deficit risk and the best sowing periods for maize (Zea mays L.) in the State of Parana, Southern Brazil. A climatological soil water balance model adapted for maize was simulated, using historical series of daily values of maximum evapotranspiration and precipitation from 32 weather stations. Soil water holding capacity was calculated using an initial soil depth of 20 cm at plant emergence, which increased exponencially up to 80 cm depth at the beginning of plant flowering, and remained constant until harvest. Ten sowing dates spaced at 10 days interval were simulated between August 20 and November 20, and the frequency of soil water deficit during the flowering period (800 degree-days after emergence) was estimated. Using cluster analysis, Parana State was classified in five homogeneous zones for soil water deficit risk. Results have shown that the North and Northwest regions have very high risk. Appropriate sowing periods with lower risks were identified for all zones.

Zoneamento agroclimático para a cultura do abacateiro no Estado do Paraná

Avocado cultivars have a great diversity of tolerance to low temperatures due to their regions of origin. The Mexican breeds are more tolerant, the West Indian breeds are more sensitive and the Guatemalan breeds have intermediate behavior. In this study, the zoning of climate risks in the state of Parana was based on the severity of frost, through the analysis of historical series of minimum temperatures in a Geographic Information System. We identified four distinct areas of risk, namely, a zone with very strong and frequent frosts where cultivation is not recommended, a zone where frosts are strong and only the cultivar Fuerte is recommended, a zone with moderate frosts and only Primavera and Margarida cultivars are not recommended, and a zone of low risk in the north and west of Parana, where all cultivars are indicated. The diversity of climates in Parana and thermal requirements of the cultivars allow the harvest during most of the year through a combination of different cultivars and growing regions.

Desenvolvimento da espinheira-santa sob diferentes intensidades luminosas e níveis de poda

M. ilicifoliahas antiulcerogenic and antigastric properties and a large pharmacological and cosmetic use not yet explored in a rational way. The development of plants submitted to various light and pruning managements was evaluated during a year. Two experiments were carried out, one in a shaded area under native species and another in a full sun light area. The experiment was conducted in a completely randomized design with six replicates and 2 plants in each experimental unit. Three pruning levels were used, plants without elimination of leaves/prune; plants with elimination of 30% of the leaves and branches; plants pruned at 20 cm above the soil. The treatments were evaluated during four periods (0; 100; 211; 331 days after pruning (DAP)). In the full sunshine area, plants submitted to the drastic prune did not develop leaves until 331 DAP. Under this light intensity the number of leaves per branch was different for each pruning level (varying from 11.2 to 15.7 without prune; and from 8.7 to 11.7 with 30% of prune), but kept constant during all evaluation periods. In the area under shade, plants submitted to drastic prune showed higher number of leaves per brunch (25.0 and 29.8 with 100 and 211 DAP, respectively) and the higher leaf area (18.0; 13.9 and 15.5 cm2 with 100, 211 and 331 DAP). The shading proved to be a better condition for the development of plants and for biomass production than the full sunlight condition. This is a very important factor to be considered to establish the growth and to define the management strategies to produce holy thorn plants. The maximum daily temperatures were reduced until 2.9oC in the shaded area in comparison to the full sunlight area. The relative air humidity varied between 63,3 and 79,4% under both conditions.