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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 Sintomas de deficiências minerais no cafeeiro(Instituto Agronômico (IAC), 1949) Franco, C. M.; Mendes, H. C.Coffee plants (Coffea arabica L.) were grown in nutrient solutions for the purpose of studying deficiency symptoms of the following elements : nitrogen, phosphorus, potassium, magnesium, calcium, sulphur and iron. The methods employed in the growing of coffee plants in the nutrient solutions are described. After preliminary tests with several nutrient solutions Hoagland's formula was selected as most suitable for the present tests. However, the quantity of phosphate employed in the basic nutrient solution was reduced to one third of that given in Hoagland's formula. This reduction in phosphate was made because of the previous results obtained by Jacob which seemed to indicate that the coffee plant requires only very small amounts of phosphorus. In the present tests phosphorus deficiency symptoms were obtained and these results suggest that Jacob's failure to obtain phosphorus deficiency symptoms may be ascribed to use of Shive's solution, which has a very high phosphate content. While growing in this complete nutrient solution his plants may have stored enough phosphorus to supply their needs later when they were transferred to the solution lacking this element. In the course of the present investigation it was found that in the nutrient solutions containing KH2PO4 and having a pH higher than 5.5, the coffee plant absorbs insufficient iron. This difficulty of iron absorption by the coffee plants grown in nutrient solution was overcome by a technique previously described that is, when iron deficiency symptoms appeared on plants being tested for other deficiencies the nutrient solution was changed and the new solution used contained no phosphate. The plants were allowed to grow in this solution for two to four days and then the phosphate was added. In this way the plants absorbed sufficient iron for their requirements. The present paper describes and the color plates illustrate the symptoms on coffee plants that were associated, in the present studies, with nutrient solutions deficient in the various elements listed.Item Sistema radicular das principais leguminosas empregadas como adubo verde em cafezal(Instituto Agronômico (IAC), 1952-07) Scaranari, H . J .; Infobzato, R .Root .systems of the following leguminous plants used for green manure in coffee plantations were studied :- Canavalia ensiformins D. C., Crotalaria juncea L., Styzolobium sp (Mucuna anã) and Glycine max (L). Merrill var. Otootan.. It was noted that the depth of the root system' of each one of the four, espécies is related id the height attained by the; plants. The deepest, root system was found to be thatf of Crotálaria juncea, followed by Canavalia esiformis, soybeans and mucuna anã. For coffee green manure purposes it is concluded that the four studied leguminous espécies can be used safely even having .most of their root system located in the first 30 cm of the soilItem Possível causa do insucesso de se cultivar cafeeiros adultos em soluções nutritivas do tipo Hoagland(Instituto Agronômico (IAC), 1956-04) Mendes, Heli CamargoSince 1946 several attempts have been made to grow coffee plants (Coffea arabica L. var. bourbon (B. Rodr.) Choussy) in Hoagland's nutrient solution. Growth of the plants is quite satisfactory in the early stages, but a rather sudden decline followed by death usually occurs when they start flowering at the age of 3 or 4 years. Preliminary observations made following the addition and withdrawal of NH4NO3 and KCl (0,125 g/l each salt) to nutrient solutions in which coffee trees at the critical age were growing showred a correlation between the addition of these salts and a satis-factory growth of the plants. These observations suggested that the decline of coffee plants growing in Hoagland's nutrient solution when they begin to flower might result from an insufficiency in the reducing power of the roots during this period. In this case the roots would be unable to use the nitrates and nitrites that would thus become toxic to them. This possibility is being further investigated.Item Clorose das folhas do cafeeiro excelsa(Instituto Agronômico (IAC), 1951-07) Costa, A. S.; Mendes, J. E. TeixeiraA type of leaf chlorosis is shown by plants of excelsa coffee growing in nursery beds in a lath house at the Instituto Agronômico, Campinas. Tests made with various elements showed that this type of chlorosis is due to iron deficiency. Seedling plants of arabica coffee growing in the same beds do not show chlorosis, but these symptoms are exhibited by arabica scions grafted on some excelsa rootstocks. Scions from chlorotic excelsa plants recover the normal color when grafted on arabica rootstock. Likewise, arabica scions that had become chlorotic after being grafted on excelsa rootstock recovered when transferred onto an arabica rootstock. Other grafting tests indicated that no pathological cause seems to be associated with this type of chlorosis, and that it is probably due to genetical characteristics of the excelsa root system that prevents the plants from absorbing enough iron from the soil imder marginal conditions.