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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)... |
Tipo: Info:eu-repo/semantics/article |
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Ano: 1959 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761959000100007 |
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Malavolta,E.; Menard,L. Neptune; Arzolla,J. D. P.; Crocomo,O. J.; Haag,H. P.; Lott,W. L.. |
Due to the great importance of coffee to the Brazilian economy, a good deal of the work carried out in the "Laboratório de Isótopos", E. E. A. "Luiz de Queiroz", Piracicaba, S. Paulo, Brazil, was dedicated to the study of some problems involving that plant. The first one was designed to verify a few aspects of the control of zinc deficiency which is common in many types of soils in Brazil. An experiment conducted in nutrient solution showed that the leaf absorption of the radiozinc was eight times as high as the root uptake; the lower surface of the leaves is particularly suited for this kind of absorption. Among the heavy metal micronutrients, only iron did not affect the absorption of the radiozinc; manganese, copper, and molybdenum brought about a... |
Tipo: Info:eu-repo/semantics/article |
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Ano: 1959 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0071-12761959000100004 |
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