Resumo
Cocoa seedlings were grown in nutrient solution in order to find out the effects of the levels of N, P, K in the substrate on growth, symptoms and chemical composition of the leaves. A 3x3x3 factorial design was used. The following conclusions can be drawn. 5.1. Among the three elements under study, only nitrogen had a positive, significant effect on growth as measured by height and dry weight. 5.2. The level of a given elements in the leaves did increase when its level in the nutrient solution was raised. On the other hand the N content was positively affected by the concentration of P in the substrate. 5.3. A decrease in the N/P and K/P rations in the leaves was observed when the nutrient solutions had, res-respectively, absence of K and N and high level both of K and N. The N/K ratio increased with the level of P in the substrate. 5.4 A highly significant positive correlation was found between N content in the leaves and dry weight. This was not the case however, insofar P and K are considered - no correlation whatsoever was observed.
Efeitos de diferentes níveis de N, P e K sôbre cacaueiros jovens (Theorema cacao L.) em solução nutritiva* * Trabalho realizado com auxílio da Fundação Rockefeller. Apresentado no XVI Congresso Brasileiro de Botânica, Itabuna, Bahia, 1965.
Henrique Vianna de Amorim; Luiz Carlos Scoton; H.P. Haag; E. Malavolta
Bolsistas do CNPq e da FAPESP nas Cadeiras de Química Biológica e de Matemática da ESALQ
SUMMARY
Cocoa seedlings were grown in nutrient solution in order to find out the effects of the levels of N, P, K in the substrate on growth, symptoms and chemical composition of the leaves. A 3x3x3 factorial design was used. The following conclusions can be drawn.
5.1. Among the three elements under study, only nitrogen had a positive, significant effect on growth as measured by height and dry weight.
5.2. The level of a given elements in the leaves did increase when its level in the nutrient solution was raised. On the other hand the N content was positively affected by the concentration of P in the substrate.
5.3. A decrease in the N/P and K/P rations in the leaves was observed when the nutrient solutions had, res-respectively, absence of K and N and high level both of K and N. The N/K ratio increased with the level of P in the substrate.
5.4 A highly significant positive correlation was found between N content in the leaves and dry weight. This was not the case however, insofar P and K are considered - no correlation whatsoever was observed.
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LITERATURA CITADA
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Datas de Publicação
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Publicação nesta coleção
27 Jun 2012 -
Data do Fascículo
1964