Alocação de biomassa e nutrientes em Heteranthera reniformis sob o efeito de N, P e K
Carregando...
Data
2005-03-01
Autores
Domingos, V.D.
Martins, D. [UNESP]
Fernandes, D.M. [UNESP]
Costa, N.V.
Paschoa, P.L. [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade Brasileira da Ciência das Plantas Daninhas
Resumo
Este trabalho objetivou estudar a distribuição de biomassa e nutrientes entre os componentes vegetativos de Heteranthera reniformis sob o efeito de diferentes concentrações de N, P e K. As plantas foram cultivadas em vasos plásticos preenchidos com pedra rolada, em soluções nutritivas a 80% da concentração original de Sarruge, sendo esta a solução-base. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro níveis (0, 25, 50 e 75% da solução-base) avaliados individualmente em N, P e K, além da testemunha (100% da solução-base), com quatro repetições no período de 35 dias. As maiores áreas foliares ocorreram em soluções com 75% de P e 50% de N e K. A solução com 50% de N proporcionou a maior biomassa seca de plantas. A contribuição do caule na alocação de recursos apresentou resultados que variaram entre 55,5 e 74,5% em relação à matéria seca total referente ao nível 0 e 75% de N; a contribuição de raízes reduziu com o aumento da concentração de N, bem como de P e K. As maiores contribuições de raízes ocorreram nas ausências de N (26,8%) e P (19,2%), os quais foram maiores em relação aos seus respectivos níveis mais concentrados. Os teores de N, P e K corresponderam a uma ordem crescente em folha, caule e raízes, em que os maiores teores foram obtidos nos níveis de 50 a 125 mg L-1 de N, 5 a 15 mg L-1 de P e 100 a 150 mg L- 1 de K.
This research aimed to study the biomass and nutrient distribution among the vegetative components of Heteranthera reniformis under the effect of different concentrations of N, P and K. The plants were cultivated in plastic pots filled with rolled stone, in nutrient solutions with 80% of the original concentration of Sarruge as the base solution. The experimental design was completely randomized, at 5 levels (0, 25, 50, 75% of the base solution) evaluated individually in N, P and K, besides the control (100% of the base solution), with 4 replicates in the period of 35 days. The largest leaf areas were verified in solutions to 75% of P and 50% of N and K. The solution up to 50% of N provided the largest dried biomass of the plants. The stem contribution to the allocation of resources presented results ranging from 55.5 to 74.5% in relation to the total dry matter regarding level 0 and 75% of N. Root contribution decreased with the increase of N, P and K concentrations. The greatest root contributions were in the absence of N (26.8%) and P (19.2%), which were higher in relation to their respective more concentrated levels. The contents of N, P and K corresponded to an increasing order in leaf, stem and roots, with the largest contents obtained in the range of 50 to 125 mg L-1 of N; 5 to 15 mg L-1 of P; and 100 to 150 mg L-1 of K.
This research aimed to study the biomass and nutrient distribution among the vegetative components of Heteranthera reniformis under the effect of different concentrations of N, P and K. The plants were cultivated in plastic pots filled with rolled stone, in nutrient solutions with 80% of the original concentration of Sarruge as the base solution. The experimental design was completely randomized, at 5 levels (0, 25, 50, 75% of the base solution) evaluated individually in N, P and K, besides the control (100% of the base solution), with 4 replicates in the period of 35 days. The largest leaf areas were verified in solutions to 75% of P and 50% of N and K. The solution up to 50% of N provided the largest dried biomass of the plants. The stem contribution to the allocation of resources presented results ranging from 55.5 to 74.5% in relation to the total dry matter regarding level 0 and 75% of N. Root contribution decreased with the increase of N, P and K concentrations. The greatest root contributions were in the absence of N (26.8%) and P (19.2%), which were higher in relation to their respective more concentrated levels. The contents of N, P and K corresponded to an increasing order in leaf, stem and roots, with the largest contents obtained in the range of 50 to 125 mg L-1 of N; 5 to 15 mg L-1 of P; and 100 to 150 mg L-1 of K.
Descrição
Palavras-chave
planta aquática, planta daninha, crescimento, nutrientes, aquatic plant, weed, growth, nutrients
Como citar
Planta Daninha. Sociedade Brasileira da Ciência das Plantas Daninhas , v. 23, n. 1, p. 33-42, 2005.