Anais da Escola Superior de Agricultura Luiz de Queiroz
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/13757
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Item Sombreamento dos cafèzais I.: resultados de três ciclos bienais (1953/1958) obtidos na escola "Luiz de Queiroz"(Universidade de São Paulo, Escola Superior de Agricultura, 1959) Graner, E. A.; Godoy Junior, C.The present paper discusses the data obtained in shade and unshaded coffee plots at Piracicaba, São Paulo, Brazil. The results, analysed statistically, can be summarized as follows: a) unshaded plots produced 17% more than shaded ones; b) the percentage of coffee berry borer infestation was higher in shaded plots as compared with unshaded ones; c) the percentage of green (not ripened fruits) depends of the harvest time. When the harvest was retarded, the percentage of green fruits was higher in the shaded plots. When the percentage of green fruits was the same, both in shaded and unshaded plots, the percentage of ripened was higher and the percentage of dried fruits was lesser in the shaded plots as compared with unshaded ones; d) other comparisons as production of dried grains by the field fruits, relation between dried fruits and dried grains and cup-test by expert coffee-taster, did not show differences among shaded and unshaded plots.Item Estudos sôbre a alimentação mineral do cafeeiro. II: Absorção do superfosfato radioativo pelo cafeeiro (Coffea arabica L., var. Bourbon Amarelo) em condições de campo(Universidade de São Paulo, Escola Superior de Agricultura, 1959) Malavolta, E.; Menard, L. Neptune; Lott, W. L.In order to find out the best way to supply phosphorus to coffee plants when growing in "terra roxa misturada", a red soil with a high fixing capacity, tagged superphosphate was applied by the following procedures: (1) topdressed in a circular strip around the trees; (2) placed in the bottom of a circular furrow 15 cm deep; (3) placed in a semicircular furrow also 15 cm deep; (4) sprayed directly to the leaves. In each case 150 gms. of ordinary superphosphate tagged with H3 P32 O4 to give 5 X 10(9) c.p.m. were given to the two and half year old coffee plants. It was found that for the several treatments of the total phosphorus in the leaves the following values, on a per cent basis, came from the applied superphosphates: (1) topdressed 10.2 per cent, (2) circular furrow 2.4 per cent, (3) semicircular furrow 1.7 per cent, (4) sprayed 38.0 per cent; one can see, then, that methods (2) and (3) commonly used by the coffee planters are a very inefficient way to supply phosphorus in this type of soil. The remarkable foliar absorption was checked twice: a water culture experiment was carried out, the radiophosphorus being supplied by brushing it in the upper and lower surfaces of a given leaf; radioactivity was detected all over the plant as a result both of absorption and translocation; on the other hand, leaves collected from the sprayed trees were radioautographed; the radioautographs showed the pattern of distribution of the P32 which indicates true absorption rather than a surface contamination. In another locality, an experiment was caried out with 8 year old plants growing in "arenito de Bauru" which is a sandy soil with much less phosphorus fixing capacity. In this experiment the aim was to compare absorption of tagged superphosphate by trees growin under mulch against plants not receiving this treatment, The uptake of phosphorus was the same for both sets of plants. In both field experiments soil samples down to 15 cm in the profile were collected and its 0.2NHC1 soluble phosphorus was counted; rather significant values were observed mainly in the upper 5 cm layers.Item Alterações morfológicas e citológicas do cafeeiro (Coffea arabica L, var. Bourbon (B. Rodr.) Choussy) cultivado em solução nutritiva decorrentes das deficiências e excessos dos macronutrientes(Universidade de São Paulo, Escola Superior de Agricultura, 1959) Accorsi, Walter R.; Haag, Henrique P.Apesar de sermos os maiores produtores de café do mundo, poucos têm sido os trabalhos fundamentais em nutrição mineral publicados em nosso meio. O presente ensaio foi iniciado em 1956, cultivando o cafeeiro em solução nutritiva. Dentre alguns dos objetivos (HAAG, 1958), destacamos os seguintes para o presente trabalho: 1. Obter um quadro sintomatológico das deficiências e dos excessos dos macronutrientes. 2. Constatar se os diversos tratamentos afetavam a constituição histológico das folhas.Item Nota preliminar sôbre a absorção e a translocação do radiozinco no cafeeiro [Coffea arabica] cultivado em solução nutritiva(Universidade de São Paulo, Escola Superior de Agricultura, 1956) Arzolla, J. Dal Pozzo; Haag, H. P.; Malavolta, E.Two water-culture experiments were carried out to study the absorption and the translocation of radiozinc in young coffee plants as influenced by two factors, namely, concentration of heavy metals (iron, manganese, copper and molybdenum) and method of application. Inert zinc was furnished at a uniform rate of 0.05 p.p.m.; the levels of iron supply were 0, 1.0 and 10 p.p.m.; manganese was supplied in three doses 0, 0.5, and 5 p.p.m.; copper - 0, 0.02, and 0.2 p.p.m.; molybdenum - 0, 0.01 and 0.1 p.p.m. When applied to the nutrient solution the activity of the radiozinc was 0.15 microcuries per plant. In the study of the leaf absorption, the radiozinc was supplied at the level of 0.10 microcuries per plant; in this case the material was brushed either on the lower or in the upper surface or both of two pairs of mature leaves. In both experiments the absorption period was 8 weeks. The following conclusions can be drawn: 1. Among the heavy metals herein investigated the iron concentration did not affecc the uptake of the radiozinc; by raising the level of Mn, Cu and Mo ten times, the absorption dropped to 50 per cent and even more whe compared with the control plant; however, when these micronutrients were omitted from the nutrient solution an increase in the uptake of zinc was registered only in the minus - Cu treatment. The effects of high leveds of Mn, Cu and Mo probably indicate an interionic competition for a same site on a common binding substance in the cell surface. 2. The absorption of the radiozinc directly applied to the leaf surface reached levels as high as 8 times that registered when the root uptake took place. Among the three methods of application which have been tried, brushing the lower surface of the leaves proved to be the most effective; this result is easily understood since the stomatal openings of the coffee leaves are preferentially located in the lower surface. In this treatment, about 40 per cent of the activity was absorbed and around 12 per cent were translocated either to the old or to the newer organs. 3. Data herein presented suggest that leaf sprays should be preferred - rather than soil applications - to control zinc deficiency in coffee plants when growing in field conditions.Item A evolução das máquinas de beneficiar café no Brasil(Universidade de São Paulo, Escola Superior de Agricultura, 1953) Leme, Hugo de AlmeidaNo estudo do histórico das Máquinas de Beneficiamento propriamente dito do café diremos, preliminarmente, que o desenvolvimento dessas máquinas acompanhou o progresso da cafeicultura.Item Variedades de cafeeiros(Universidade de São Paulo, Escola Superior de Agricultura, 1948-07-15) Mendes, Carlos TeixeiraNo estudo das variedades de cafeeiros que povoam o Estado de São Paulo, além de mil outros detalhes correlacionados com sua cultura e sua genética (produtividade, rusticddade etc.) podemos levar em consideração outros dois pontos de vista : o da "bebida" e o do "tipo". Em relação à primeira, não será preciso perder muito tempo para demonstrar que as variedades predominantes em nossas culturas não constituem a causa das bebidas finas ou das menos boas. Ao meio em que vivem é que se deve imputar, mais que a tudo, a razão do fato. As duas variedades que englobam de modo quase absoluto, nossas culturas, são a "Nacional" e a "Burbon", as, mesmas que, de Campinas para o Norte do Estado produzem afamados cafés e que, na Sorocabana te no vale do Paraiba só contribuem com produtos indiscutivelmente inferiores aos daquela zona.Item A broca do café (Hipothenemus Hampei, Ferrari, 1867)(Universidade de São Paulo, Escola Superior de Agricultura, 1946) Godoy Júnior, CarivaldoA finalidade deste trabalho é a de verificar a procedência ou não das afirmações de vários observadores sobre a infestação da broca, com referência às partes altas e baixas de um cafezal e com referência aos pontos cardeais; finalmente, aproveitámos a oportunidade para estudar, sob o mesmo aspeto, uma parte abandonada.